Study: Whooping cough resurgence due to vaccinated people not knowing they’re infectious?

Public Release: 24-Jun-2015

Santa Fe Institute

Credit: Courtesy of B. Althouse and S. Scarpino

Whooping cough has made an astonishing comeback, with 2012 seeing nearly 50,000 infections in the U.S. (the most since 1955), and a death rate in infants three times that of the rest of the population. The dramatic resurgence has puzzled public health officials, who have pointed to the waning effectiveness of the current vaccine and growing anti-vaccine sentiment as the most likely culprits.

But that might not be the whole story, suggests a new study published in BMC Medicine by Santa Fe Institute Omidyar Fellows Ben Althouse and Sam Scarpino. Their research points to a different, but related, source of the outbreak — vaccinated people who are infectious but who do not display the symptoms of whooping cough, suggesting that the number of people transmitting without symptoms may be many times greater than those transmitting with symptoms.

In the 1950s, highly successful vaccines based on inactivated pertussis cells (the bacteria that causes whooping cough) drove infection rates in the U.S. below one case per 100,000 people. But adverse side effects of those vaccines led to the development and introduction in the 1990s of acellular pertussis vaccines, which use just a handful of the bacteria’s proteins and bypass most of the side effects. (Currently given to children as part of the Tdap vaccine.)

The problem is, the newer vaccines might not block transmission. A January 2014 study in PNAS by another research team demonstrated that giving baboons acellular pertussis vaccines prevented them from developing symptoms of whooping cough but failed to stop transmission.

Building on that result, Althouse and Scarpino used whopping cough case counts from the CDC, genomic data on the pertussis bacteria, and a detailed epidemiological model of whooping cough transmission to conclude that acellular vaccines may well have contributed to — even exacerbated — the recent pertussis outbreak by allowing infected individuals without symptoms to unknowingly spread pertussis multiple times in their lifetimes.

‘There could be millions of people out there with just a minor cough or no cough spreading this potentially fatal disease without knowing it,’ said Althouse. ‘The public health community should act now to better assess the true burden of pertussis infection.’

What’s worse, their model shows that if the disease can be spread through vaccinated, asymptomatic individuals essentially undetected, the level of vaccination needed to protect those that are unvaccinated (so-called ‘herd immunity’) is over 99 percent, impractically high at a time when anti-vaccine campaigns are turning people away from vaccination.

Their results also suggest that a practice called cocooning, where mothers, fathers, and siblings are vaccinated to protect newborns, isn’t effective. ‘It just doesn’t work, because even if you get the acellular vaccine you can still become infected and can still transmit. So that baby is not protected,’ Althouse says.

Does this mean the current vaccine is useless? Not at all, the pair says. Until researchers can develop a new pertussis vaccine that blocks transmission, the protection the acellular vaccine offers to individuals is vital.

‘It’s the symptoms of pertussis infection that kill people,’ Scarpino says, ‘and the existing vaccine prevents the most debilitating effects of whooping cough.’

In that sense, the research underscores the importance of getting vaccinated, especially for children. ‘There are lots of people out there who may be transmitting pertussis unknowingly,’ Scarpino says. ‘Not vaccinating your own child puts her or him at increased risk of severe disease, even death.’

Journal Reference:

  1. Benjamin M. Althouse, Samuel V. Scarpino. Asymptomatic transmission and the resurgence of Bordetella pertussis. BMC Medicine, 2015; 13 (1) DOI: 10.1186/s12916-015-0382-8

Rubella vaccination used to induce behavioral problems in children


Psychoneuroendocrinology. 1998 May;23(4):337-51.
Influence of socioeconomic status on behavioral, emotional and cognitive effects of rubella vaccination: a prospective, double blind study.
– Effects of vaccination with live attenuated Rubella virus on psychological parameters measured in 12-year-old girls with low socioeconomic status before, and 10 weeks after, the vaccination. Compared to their own baseline and to the levels in girls who were already immune to Rubella before vaccination (control group), subjects who seroconverted following vaccination (experimental group) showed significantly increased levels of total and emotional depression, measured by the Children Depression Inventory, and significantly higher incidence of social and attention problems and delinquent behavior, assessed by the Achenbach Child Behavior Checklist. (Adapted from Morag et al.13) Continue reading “Rubella vaccination used to induce behavioral problems in children”

74 percent of parents would remove their kids from daycare if others are unvaccinated

41 percent of parents say under-vaccinated kids should be excluded from daycare, according to U-M’s National Poll on Children’s Health

ANN ARBOR, Mich. – Most parents agree that all children in daycare centers should be vaccinated, and that daycare providers should be checking vaccine records every year, according to the University of Michigan C.S. Mott Children’s Hospital National Poll on Children’s Health.

All states require vaccines for children who attend daycare, but those requirements may not include every vaccine from birth to age 5 years. As a result, some children still don’t receive all recommended vaccines–leaving daycare providers and parents to decide how to handle the situation of a child who is not up-to-date on vaccines.

In this national sample of parents of child 0-5 years, most indicate that daycare providers should review children’s immunization status every year to ensure they are up-to-date (52 percent strongly agree, 22 percent agree).

“Results of this poll indicate that most parents want strong policies around making sure children in daycare are up-to-date on vaccines,” says Sarah J. Clark, M.P.H. , associate director of the National Poll on Children’s Health and associate research scientist in the University of Michigan Department of Pediatrics. “Checking vaccination records every year is beyond the scope of many state requirements, and may represent a significant change in practice at many daycares.”

The poll gave parents a scenario where 1 in 4 children in their daycare center were not up-to-date on vaccines. In response to this scenario, 74 percent of parents would consider removing their own child from the daycare.

“This scenario mirrors the national statistics that show approximately 25 percent of preschool children in the United States are not fully vaccinated,” says Clark. “Parents may not realize that so many children are not up-to-date; in some daycares, this scenario is a reality.” Continue reading “74 percent of parents would remove their kids from daycare if others are unvaccinated”

Vaccines in the short-term may accelerate the transition from subclinical MS to overt autoimmunity in patients with existing disease

Vaccines and the Risk of Multiple Sclerosis and Other Central Nervous System Demyelinating Diseases

JAMA Neurol. Published online October 20, 2014. doi:10.1001/jamaneurol.2014.2633

Importance  Because vaccinations are common, even a small increased risk of multiple sclerosis (MS) or other acquired central nervous system demyelinating syndromes (CNS ADS) could have a significant effect on public health.

Objective  To determine whether vaccines, particularly those for hepatitis B (HepB) and human papillomavirus (HPV), increase the risk of MS or other CNS ADS.

Design, Setting, and Participants  A nested case-control study was conducted using data obtained from the complete electronic health records of Kaiser Permanente Southern California (KPSC) members. Cases were identified through the KPSC CNS ADS cohort between 2008 and 2011, which included extensive review of medical records by an MS specialist. Five controls per case were matched on age, sex, and zip code.

Exposures  Vaccination of any type (particularly HepB and HPV) identified through the electronic vaccination records system.

Main Outcomes and Measures  All forms of CNS ADS were analyzed using conditional logistic regression adjusted for race/ethnicity, health care utilization, comorbid diseases, and infectious illnesses before symptom onset.

Results  We identified 780 incident cases of CNS ADS and 3885 controls; 92 cases and 459 controls were females aged 9 to 26 years, which is the indicated age range for HPV vaccination. There were no associations between HepB vaccination (odds ratio [OR], 1.12; 95% CI, 0.72-1.73), HPV vaccination (OR, 1.05; 95% CI, 0.62-1.78), or any vaccination (OR, 1.03; 95% CI, 0.86-1.22) and the risk of CNS ADS up to 3 years later. Vaccination of any type was associated with an increased risk of CNS ADS onset within the first 30 days after vaccination only in younger (<50 years) individuals (OR, 2.32; 95% CI, 1.18-4.57).

Conclusions and Relevance  We found no longer-term association of vaccines with MS or any other CNS ADS, which argues against a causal association. The short-term increase in risk suggests that vaccines may accelerate the transition from subclinical to overt autoimmunity in patients with existing disease. Our findings support clinical anecdotes of CNS ADS symptom onset shortly after vaccination but do not suggest a need for a change in vaccine policy.

Continue reading “Vaccines in the short-term may accelerate the transition from subclinical MS to overt autoimmunity in patients with existing disease”

15 Syrian Children Die of UN Measles Vaccines

Thursday, 18 September 2014

The UN has halted a measles vaccination campaign in northern Syria after at least 15 children died after receiving shots, the UN Children’s Fund (UNICEF) and World Health Organization (WHO) confirmed in a joint statement.

“UNICEF and WHO have been shocked and saddened to learn of the deaths of at least 15 young children in Idlib, Syria,” the statement said. “The deaths of the children occurred in areas where a measles immunization campaign had been under way.”

The children were all under the age of two, Reuters reported, citing aid workers.

Around one hour after being given a second round of the measles vaccine in Idlib on Tuesday, the children demonstrated signs of “severe allergic shock,” said Abdullah Ajaj, a physician administering the vaccinations at a medical center in Jarjanaz, according to AP. The second round of vaccinations began in Idlib and Deir Ezzour on Monday.

Following the vaccine, some of the children’s bodies swelled and they suffocated to death. Continue reading “15 Syrian Children Die of UN Measles Vaccines”

Live virus used in polio vaccine can evolve and infect, warns TAU researcher

” Can act like wild poliovirus and continue the threat of contagion ”  November 7, 2011 _ Requested Re-Post from our HRR Site

Health professionals and researchers across the globe believe they are on the verge of eradicating polio, a devastating virus which can lead to paralysis and death. Despite successful eradication in most countries, there are still four countries where the virus is considered endemic — and many more in which the virus still lurks.

Dr. Lester Shulman of Tel Aviv University’s Sackler Faculty of Medicine and the Israeli Ministry of Health has spent years tracking isolated cases of live poliovirus infections, often discovered in countries that are supposedly polio-free. When the live-virus version of the vaccine, called Oral Polio Vaccine (OPV) evolves, he says, it can act like wild poliovirus and continue the threat of contagion.

None - This image is in the public domain and ...

Continue reading “Live virus used in polio vaccine can evolve and infect, warns TAU researcher”

Vaccines cause many children to develop allergies to aluminum

Public release date: 14-Dec-2010: HRR Requested Re-Post

The following is the author's description of t...

‘Pruritic nodules’ are small lumps under the skin that cause itching and which, according to some studies, can remain for several years. A study of whooping cough vaccinations in Gothenburg a few years ago showed that almost one per cent of the children developed pruritic nodules in the area of the vaccination. Three out of four of the children who had a reaction with nodules also developed an allergy to aluminium.

“This was completely unexpected. Aluminium has been used as an adjuvant, intensifier, in vaccines for over 70 years with only a small number of reports of pruritic nodules and allergic contact dermatitis”, says Eva Netterlid. Her research has been carried out at the Occupational and Environmental Dermatology Unit in Malmö. Continue reading “Vaccines cause many children to develop allergies to aluminum”

Dosing schedule of pneumococcal vaccine linked with increased risk of getting multiresistant strain

Public release date: 7-Sep-2010 – EEV: Requested Re-Post from the HRR site.

Infants who received heptavalent pneumococcal conjugate vaccination (PCV-7) at 2, 4, and 11 months were more likely than unvaccinated controls to have nasopharyngeal acquisition of pneumococcal serotype 19A

– the increase in serotype 19A disease was associated in time with the widespread implementation of PCV-7 in routine infant immunization programs

– A rapid increase in the presence of pneumococcal serotype 19A strains that are often multiresistant to antibiotics has been observed over the last decade

– serotype 19A is now the leading causative pneumococcal serotype of invasive and respiratory pneumococcal disease

Question mark in Esbjerg
Question mark in Esbjerg (Photo credit: alexanderdrachmann)

Infants who received heptavalent pneumococcal conjugate vaccination (PCV-7) at 2, 4, and 11 months were more likely than unvaccinated controls to have nasopharyngeal (in the nasal passages and upper part of the throat behind the nose) acquisition of pneumococcal serotype 19A, a leading cause of respiratory pneumococcal disease, according to a study in the September 8 issue of JAMA. Continue reading “Dosing schedule of pneumococcal vaccine linked with increased risk of getting multiresistant strain”

Brief fever common in kids given influenza, pneumococcal vaccines together

PUBLIC RELEASE DATE:
6-Jan-2014

– Parents should be made aware that their child might develop a fever following simultaneous influenza and pneumococcal vaccinations

– children who received simultaneous influenza and pneumococcal vaccines, about a third (37.6 percent) had a fever of 100.4 F (38 C) or higher on the day of or day after vaccination, compared with children who received only the pneumococcal (9.5 percent) or only the influenza (7.5 percent) vaccine.

Findings suggest utility of text messaging to monitor safety

NEW YORK, NY (Jan. 6, 2014) – Giving young children the influenza and pneumococcal vaccines together appears to increase their risk of fever, according to a study led by researchers from Columbia University Medical Center (CUMC) and the Centers for Disease Control and Prevention (CDC). However, the fever was brief, and medical care was sought for few children, supporting the routine immunization schedule for these vaccines, including the recommendation to administer them simultaneously. The study, which looked at children 6-23 months old, was published online on Jan. 6, 2014, in JAMA Pediatrics. Continue reading “Brief fever common in kids given influenza, pneumococcal vaccines together”

Vaccine’s, the Lucky Rabbits Foot, and Shhh No questions allowed ( Part 1 )

Vaccines are just a form of medicine like everything else. Some of them good, and some of them not so good. In any case you have a right to know.

Just remember Scientific Method – Observation, Hypothesis, and Theory as well as Risk to Benefit Ratio ..> But don’t get me started on Epigenetics

We should all have the freedom to inoculate ourselves based upon fact… The first one However, I threw in for fun ; )

There are many more as this is just part 1 …. Just sticking with RECENT Peer Review. But let the first Salvo fly

Change in human social behavior in response to a common vaccine and Funvax Using Vaccines to Alter Human Behavior VMAT2 Gene 

Pneumococcal vaccination in adults does not appear to work

Live Vaccination against ( German Measles ) Rubella caused Signifigant Depression up to 10 weeks – Vaccines/ Bacteria Can Alter Mood and Behavior

No significant influenza (FLU) vaccine effectiveness could  be demonstrated for any season, age or setting after adjusting for county, sex, insurance, chronic conditions recommended for influenza vaccination and timing of influenza vaccination

The Hidden Threat That Could Prevent Polio’s Global Eradication – Vaccinated Children that Become  “chronic excreters”

U.S. Court Confrims M.M.R. Vaccine Caused Autism or Cumulative  (Verified through Multiple Sources) From DEC 2012 Judgment

Pig Virus DNA Found in Rotavirus Vaccine : Millions of children worldwide, including 1 million in the U.S. exposed

Seasonal flu vaccination increase the risk of infection with pandemic H1N1 flu by 68%

Flu vaccine may not protect seniors well / Vaccine was totally ineffective

OHSU research suggests America may over-vaccinate

Some children vaccinated against hepatitis B may have an increased risk of MS

Flu shot does not cut risk of death in elderly / no decrease in hospital admissions or all-cause mortality

Measles, Mumps, Rubella vaccine linked with 2-fold risk of seizures

‘MMR vaccine causes autism’ claim banned – Followed by 15 studies that link Strong Correlation, it May

Influenza Vaccine Failure among Highly Vaccinated Military Personal, No protection against Pandemic Strains.

Live virus used in polio vaccine can evolve and infect, warns TAU researcher

India: Paralysis cases soar after oral polio vaccine introduced

Flu Vaccine offers no Protection in seniors

Common cold virus can cause polio in mice when injected into muscles

Flu shot does not reduce risk of death

Swine flu vaccine linked to child narcolepsy: EU Confirmation

WHO and the pandemic flu “conspiracies” – FULL report from the BMJ and The Bureau of Investigative Journalism  2010

A vaccine-derived strain of poliovirus that has spread in recent years is serious but it can be tackled with an existing vaccine

Dosing schedule of pneumococcal vaccine linked with increased risk of getting multiresistant strain

Expert questions US public health agency advice on influenza vaccines

Whooping Cough Vaccine is obsolete ” Bulk of the cases were in fully vaccinated children ” few cases among unvaccinated children

Flu vaccine backfires in pigs / vaccinated against H1N2 influenza were more vulnerable to the rarer H1N1 strain

Higher anaphylaxis rates after HPV vaccination: CMAJ study / significantly higher – 5 to 20 fold – than that identified in comparable school-based vaccination programs

Allergic to Gummy Bears? Be Cautious Getting the Flu Shot

Vaccination campaign doubles HBV mutations

Vaccination campaign doubles HBV mutations

Contact: Garth Hogan ghogan@asmusa.org 202-942-9389 American Society for Microbiology

WASHINGTON, DC – October 7, 2013 – A universal infant vaccination campaign in China has led the Hepatitis B virus (HBV) to more than double its rate of “breakout” mutations. These mutations may enable the virus to elude the vaccine, necessitating new vaccination strategies. Researchers at the Chinese Centers for Disease Control and Prevention and University of North Carolina, Chapel Hill, report their findings in an article published ahead of print in the Journal of Virology.

Until a universal vaccination program for infants was implemented in 1992, nearly ten percent of Chinese—children included—were infected with HBV. The vaccination campaign has protected an estimated 80 million children, dramatically reducing the percentage of children under 5 who are infected, from nearly 10 percent in 1992 to less than one percent in 2005. But these gains are in danger of being eroded as the virus develops surface mutations.

Taking advantage of 1992 and 2005 survey, investigators found that the prevalence of HBV escape mutants in children rose from 6.5 percent in 1992, before the start of the universal vaccination program, to nearly 15 percent in 2005. Among the control group of adults unaffected by the universal vaccination campaign, the rate of break-out mutants was virtually unchanged.

Hepatitis B is an infectious illness of the liver which can cause vomiting, inflammation, jaundice, and, rarely, death. About a third of the world’s population has been infected at some point in their lives. Transmission of hepatitis B virus results from exposure to infectious blood or bodily fluids containing blood. The infection is preventable by vaccination, which has been routinely used since the 1980s.

Researcher Tao Bian of Chapel Hill says that the vaccine remains quite effective, but that because escape mutants are likely to increase, public health officials need to track the rise of escape mutants, in order to know when it becomes time to consider new vaccination strategies. Measures that might be taken include boosting doses, adjusting the timing of vaccinations, or improving the vaccine. A next generation HBV vaccine has been invented, containing a second antigen in addition to the virus’ surface antigen. That means that both antigens would have to develop breakout mutations in order to elude the vaccine.

###

 

A copy of the manuscript can be found online at http://bit.ly/asmtip0913e.  Formal publication is scheduled for the November 2013 issue of the Journal of Virology.

The Journal of Virology is a publication of the American Society for Microbiology (ASM). The ASM is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM’s mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

Whooping Cough Vaccine is obsolete ” Bulk of the cases were in fully vaccinated children ” few cases among unvaccinated children

Why Whooping Cough Vaccines Are Wearing Off

Doctors race to protect kids as whooping cough vaccines wear off

By Maryn McKenna  | Tuesday, October 1, 2013

By late summer 2010 an alarming number of children in California had developed pertussis, or whooping cough—five times as many as in the first half of 2009. David Witt, a physician and infectious disease specialist who works at Kaiser Permanente San Rafael Medical Center, cared for some of those sick children. His practice lies in the heart of Marin County, the famously counterculture spit of land north of San Francisco. At first, he assumed that the outbreak was a consequence of parents refusing vaccinations for their children. As the incidence continued to climb month after month, however—not just in northern California but all across the state—Witt began to wonder whether something else was going on.

Working with his college-age son Maxwell and his pediatrician colleague Paul Katz, Witt retrieved the records for 132 Kaiser Permanente patients younger than 18 who had tested positive for pertussis between March and October 2010.

“The bulk of the cases were in fully vaccinated children between eight and 12 years old,” Witt says. “That was a total surprise.”

As Witt’s small study spotted, and larger ones have since confirmed, protection granted by the vaccine, which has been used for the past two decades, is wearing off much faster than public health planners anticipated. Rates of pertussis increased at least threefold between 2011 and 2012 in 21 states. Whereas some of these cases occurred among children who had never been vaccinated, most of the affected children had in fact received vaccines; those inoculations simply failed to safeguard them over the long term.

Now health authorities are scrambling to devise new strategies for protecting kids. There are no easy solutions. No one is developing a better vaccine to replace the current one. Attempting to recommend additional shots would trigger years of public health debate, and it is not clear whether extra doses of vaccine would make a difference. Even discussing the problem provokes uneasiness: with antivaccine sentiments and vaccine refusal at historic highs, nobody wants to impeach one of public health’s crucial tools.

Adverse Reactions Before a vaccine became available in the 1940s, many parents learned firsthand that pertussis was a terrible disease. The bacterium that causes it, Bordetella pertussis, produces a toxin that damages the tiny sweeping hairs that coat the lining of the lungs, preventing them from clearing the airways of mucus and the microbial invaders. Following uncontrollable coughing fits—some of which are strong enough to cause seizures and brain damage—children wheeze and gasp for breath, giving the illness its name. In the pre-vaccine era, whooping cough afflicted as many as 200,000 children each year in the U.S. and killed about 8,000. The new vaccine shrank the incidence of pertussis from around 157 cases for every 100,000 members of the population to one in 100,000.

This success came at a cost, though. Researchers crafted the original pertussis vaccine from dead pertussis bacteria that could not reproduce but retained many microbial proteins by which immune cells could recognize and attack B. pertussis before it caused disease. Unfortunately, those whole-cell preparations also contained other molecular components that could cause unwanted immune system reactions, such as swelling near the injection site and, in rare cases, high fevers that could dangerously inflame the brain. “People didn’t pay much attention to the reactions in the early days, because the death rate before the vaccine came along had been so staggering,” says James Cherry, a longtime professor of pediatrics and vaccine researcher at the David Geffen School of Medicine at U.C.L.A.

Over the next few decades, however, concern surrounding the vaccine’s side effects intensified. In the 1970s Sweden and Japan ceased using the vaccine altogether. A government study published in England in 1981 concluded that the vaccine caused permanent brain damage once in every 310,000 doses (a result that was later disputed). And in 1982 an NBC broadcast aired criticisms of the vaccine, turning public opinion against it and jump-starting the U.S. antivaccine movement.

The U.S. and other countries began industry-wide efforts to find a better vaccine, focusing on “acellular” formulas that used a few purified bacterial proteins to establish immunity rather than the whole cell, reducing the risk of inflammatory reactions. Researchers combined the new pertussis vaccine with vaccines against tetanus and diphtheria. DTaP, as it was known, was ready for the doctor’s office in 1992. In the U.S., children receive it at two, four and six months; once between 15 and 18 months; and once between the ages of four and six, before they enter school.

From the start, public health authorities understood that an acellular vaccine might confer more temporary immunity than the problematic whole-cell vaccine. So, in 2005, they added a booster to the regimen to guarantee that children would be protected throughout adolescence. Officials determined the booster would be most effective for 11- to 12-year-olds but authorized it for use in any adult, eventually including pregnant women.

A Failure to Protect After California’s 2010 pertussis outbreak, additional outbreaks hit Wisconsin, Vermont and Washington, among other states, in 2012. Analyses of who was getting sick revealed the same pattern every time. Tom Clark, a physician and pertussis expert at the Centers for Disease Control and Prevention, describes it as a “striking stair-step appearance, rising by year: six, seven, eight, nine, 10 years old. If you go back several years [to when whole-cell vaccines were used], that stair-step is not there.”

The stair-step indicated that the more time elapsed since a child’s most recent pertussis shot, the more likely the child would develop whooping cough after exposure to the bacteria. Many of these children were too young to have received their booster, so researchers hoped that once children got their additional shots, the unpredicted vulnerability would cease. New data from the Washington State outbreak quashed that hope: 13- and 14-year-olds were catching pertussis even after they received their booster shot. Other studies demonstrated that the vaccine was behaving differently from the older, reactive one: children who had received even one dose of the older, whole-cell formula while it was still on the market were better protected against pertussis than those who received only the newer vaccine. (Of course, children who received the new vaccine were still better off than those who had never been vaccinated.)

Clark points out that the original research on acellular vaccine in the 1980s tested whether it would protect but not for how long it would protect. Some diseases for which acellular vaccines are typically used, such as Hib meningitis, are only dangerous to children for a short time early in life, so long-lasting immunity is not necessary. Today, however, immunologists have better laboratory tools and a much more nuanced understanding of how immunity is evoked and sustained. “A lot of what you would do to develop a vaccine today was never done for the pertussis vaccine,” Clark says.

“The big answer is that we need a better vaccine,” says Mark Sawyer, a professor of clinical pediatrics at the University of California, San Diego, and chair of a working group collaborating with the Advisory Committee on Immunization Practices (ACIP), which helps to set federal vaccine policy. “But the ACIP can’t just make that happen. That is up to the scientists who would do a study of what would make a better vaccine, and it is up to the pharmaceutical companies.”

If a new vaccine were formulated, demonstrating its superiority would be challenging. Every developed country vaccinates its children against pertussis, so there is no large unprotected population that could help prove a new vaccine’s worth. And before encouraging manufacturers to consider developing a new vaccine, federal planners would have to weigh the unintended consequences of the endeavor. Diverting too much of the manufacturers’ limited resources to one new vaccine could cause shortages of others, for example. Another concern is whether parents would heed the advice to bring children in for yet more shots.

The ACIP has been researching the problem for more than a year. The committee is in uncharted territory because this type of failure has never occurred with any other vaccine. In June the working group concluded that because the booster’s protection against pertussis is so short-lived, adding more shots to the typical regimen would do little to reduce the overall prevalence of pertussis. The group therefore advised the committee not to change policy to include a second booster in adulthood but rather to increase the number of pregnant women who get their booster in the first place. The CDC estimates that currently only 6 percent of pregnant women receive the shot. Yet newborns, who cannot be vaccinated, are the most vulnerable to the dangerous effects of pertussis; improving the immunity of their closest contacts could be the best way to prevent pertussis deaths.

Given the current vaccine’s faults, Clark says bluntly that in the general population “there’s going to be a lot of pertussis.” But he adds that although pertussis cases are increasing, deaths are not; when vaccinated children develop whooping cough, they have milder symptoms. So the newer pertussis vaccines are still valuable because they reduce not just the likelihood of death and severe illness but also the health care spending—not to mention emotional trauma—that accompany those dire results. On that basis, Sawyer says, public health officials should urge the 90 percent of American teens and adults who failed to get their booster shot to receive one and thereby protect both themselves and the most vulnerable among us. “We do need a new vaccine,” he says. “But we can do a lot better with the ones we have.”

http://www.scientificamerican.com/article.cfm?id=why-whooping-cough-vaccines-are-wearing-off

Shame Tags for Vaccine Refusers

No checklist for doctors giving immunisation benefits advice

 

  • by: SUE DUNLEVY National Health Reporter
  • From:         News Limited Network
  • June 06, 2013 10:53PM

A baby gets an injection. Vaccination. Child. Syringe. Generic image.

A baby gets an injection. Vaccination. Child. Syringe. Generic image. Source: Supplied

PARENTS who refuse to vaccinate their children may not be getting comprehensive information on the benefits of immunisation because there is no checklist for doctors to follow.

Department of Health and Ageing officials have told a Senate estimates committee that they are not aware of a checklist for medical practitioners when counselling parents who don’t want to protect their children from infectious diseases.

Asked by doctor and Greens Senator Richard di Natale whether doctors were assisted in their counselling by such a checklist a departmental official replied: “Not that I’m aware of”.

Senator di Natale said vaccines saved lives.

“It’s really important that parents are made fully aware of the risks they would be exposing their children to if they refuse to vaccinate,” he said.

Parents who refuse to vaccinate their children must undergo a counselling session with a medical practitioner and get them to sign a conscientious objection form to claim the childcare rebate and get their child into a childcare centre.

The department is moving to make conscientious objection to immunisation a more distasteful option by changing the terminology applied to these parents.

Conscientious objection forms are undergoing a name change to become “vaccine refuser” forms, the department told the Senate.

At the same time, the Health Department is working with the Families Department to change the legislation which allows conscientious objectors to vaccines to receive a childcare rebate.

The words “vaccine refuser” would replace conscientious objector in the legislation if this proceeds.

Australian Medical Association president Dr Steve Hambleton said he did not think doctors required a checklist for counselling parents who did not want to vaccinate their children.

The Academy of Science’s Myths and Realities booklet, available on the internet, was a good resource for doctors to use in this situation, he said.

Only a minority of parents were hard core anti-vaccination and most parents listened and changed their mind when they talked through issues with their doctors, he said.

Dr Hambleton supported the idea of changing government terminology for parents who won’t vaccinate their kids from conscientious objectors to vaccine refusers.

“I support that. The reality is there is no good medical reason to be a conscientious objector,” he said.

“Vaccine refusers says it like it is, they should be named for what they do,” he said.

The DoH has also revealed that the take up rate of the cervical cancer vaccine by teenage girls lags well behind childhood immunisation rates.

While around 90 per cent of young children are immunised only 70 per cent of 15 year old girls have had the cervical cancer vaccine.

Departmental officials speculated that this might be because parents were likely to consult a teenage girl on whether she wanted the jab.

http://www.heraldsun.com.au/lifestyle/health-fitness/no-checklist-for-doctors-giving-immunisation-benefits-advice/story-fni0dgux-1226658994898

 

Sweden confirms swine flu vaccine and narcolepsy

Saturday, 30 March 2013

The swine flu vaccine Pandemrix has a direct link to causing narcolepsy, especially among the younger people who were vaccinated, a new Swedish study revealed on Tuesday.

The Swedish Medical Products Agency (Läkemedelsverket) ordered the massive study to determine if the vaccine had any connection to narcolepsy after dozens of reported cases of young people coming down with the affliction after receiving a swine flu jab.

The study, which took place between October 2009 and the December 2011, compared 3.3 million vaccinated Swedes with 2.5 million who were not vaccinated.

“We can see that over the whole study period we have 126 cases of those vaccinated getting narcolepsy,” Ingemar Person, professor behind the study, said in a statement on Tuesday.

“There were 20 cases among those not vaccinated. We’re talking about a threefold increase in risk.”

The risk was found to be highest among the youngest people who took the vaccines. For those under the age of 21, the risk of contracting narcolepsy was three times higher for those who were vaccinated with Pandemrix, whereas those aged between 21 and 30 had double the risk.

Those vaccinated over the age of 40 had the same risk as those who didn’t, according to the study.

Person added that it was “very difficult” to determine whether there was any connection with other sicknesses or diseases from taking the vaccine.

http://macedoniaonline.eu/content/view/23020/54/

Increased risk of sleep disorder in children who received swine flu vaccine : Up to 16-fold increased risk

Contact: Emma Dickinson edickinson@bmjgroup.com 44-020-738-36529 BMJ-British Medical Journal

Results consistent with findings from Finland and Sweden, but may still be overestimated

The results are consistent with previous studies from Finland and Sweden and indicate that the association is not confined to Scandinavian populations. However, the authors stress that the risk may still be overestimated, and they call for longer term monitoring of the cohort of children and adolescents exposed to Pandemrix to evaluate the exact level of risk.

In 2009, pandemic influenza A (H1N1) virus spread rapidly, resulting in millions of cases and over 18,000 deaths in over 200 countries. In England the vaccine Pandemrix was introduced in October 2009. By March 2010, around one in four (24%) of healthy children aged under 5 and just over a third (37%) aged 2-15 in a risk group had been vaccinated.

In August 2010 concerns were raised in Finland and Sweden about a possible association between narcolepsy and Pandemrix. And in 2012 a study from Finland reported a 13-fold increased risk in children and young people aged 4-19.

But a lack of reported cases in other countries led to speculation that any possible association might be restricted to these Scandinavian populations.

Narcolepsy is a chronic disorder of excessive daytime sleepiness, often accompanied by sudden muscle weakness triggered by strong emotion (known as cataplexy). To evaluate the risk after vaccination in England, a team of researchers reviewed case notes for 245 children and young people aged 4-18 from sleep centres and child neurology centres across England.

Of these, 75 had narcolepsy (56 with cataplexy) with onset after 1 January 2008. Eleven had been vaccinated before onset of symptoms; seven within six months.

After adjusting for clinical conditions, vaccination at any time was associated with a 14-fold increased risk of narcolepsy, whereas vaccination within six months before onset was associated with a 16-fold increased risk.

In absolute numbers, this means that one in 52,000 to 57,500 doses are associated with narcolepsy, say the authors.

They write: “The increased risk of narcolepsy after vaccination with ASO3 adjuvanted pandemic A/H1N1 2009 vaccine indicates a causal association, consistent with findings from Finland. Because of variable delay in diagnosis, however, the risk might be overestimated by more rapid referral of vaccinated children.”

While further use of this vaccine for prevention of seasonal flu seems unlikely, they say their findings “have implications for the future licensure and use of AS03 adjuvanted pandemic vaccines containing different subtypes such H5 or H9.”

And they conclude: “Further studies to assess the risk, if any, associated with the other A/H1N1 2009 vaccines used in the pandemic, including those with and without adjuvants, are also needed to inform the use of such vaccines in the event of a future pandemic.”

Poultry disease vaccine brings short-term results but long-term problems: live vaccines that protect poultry against Newcastle Disease may be altering the genetic makeup of the wild virus strains

2010 study posted for filing

Contact: Amitabh Avasthi axa47@psu.edu 814-865-9481 Penn State

Attenuated live vaccines that protect poultry against Newcastle Disease may be altering the genetic makeup of the wild virus strains, which could make future outbreaks unpredictable and difficult to tackle, according to biologists.

Newcastle Disease is an economically devastating poultry disease that costs the industry millions of dollars.

“Many vaccines in the animal industry are developed by modifying a virulent live virus,” said Mary Poss, professor of biology and veterinary and biomedical sciences, Penn State. “These vaccines elicit a strong protection against disease.”

However, vaccinated birds can shed the vaccine virus to infect other birds, and live virus vaccines do not always protect birds from infection from other viral strains of Newcastle disease.

Poss and her Penn State colleagues Yee Ling Chong, graduate student in biology; Abinash Padhi, post-doctoral fellow and Peter J. Hudson, Willaman professor of biology, found that one vaccine strain recombined — exchanged genetic material — with at least three wild strains, creating new viruses. These viruses are found in both domestic and wild birds. The team’s findings appear today (Apr. 22) in PLoS Pathogens.

“Our findings indicate that birds can be simultaneously infected with the live virus vaccine and several other strains of this avian virus,” said Poss. “This raises concerns that modified live virus vaccines, though effective, may combine with circulating viruses to create unpredictable new strains.”

A modified live virus vaccine is essentially a weakened virus that does not cause disease but mimics a natural infection that in turn evokes a strong immune response from the infected host. But Poss argues that vaccination may be unwittingly increasing the diversity of Newcastle Disease viruses that are circulating in wild birds.

For instance, many poultry farmers typically vaccinate the flock by mixing the vaccine in the birds’ drinking water or by aerosol, which means wild birds and pigeons can also become infected with the vaccine virus.

This sets up the opportunity for viral recombination. A bird is infected with two different viruses at the same time, one from the weakened vaccine and one naturally, and both viruses then infect the same cell.

In addition to the possibility of creating new viruses, different strains of the virus that causes Newcastle disease may be evolving in different environments. Recombination among these strains could bring together genes that have multiple means to evade immunity in a host.

Poss added that vaccine developers need to be aware of the potential for driving virus evolution using modified live viruses and should instead consider using killed or inactivated viruses. Scientists are already using that approach against Newcastle Disease in some areas but not globally.

“We need to step up the surveillance and monitoring of viral diseases in poultry and wild birds,” said Poss. “We need to be aware that management practices including the use of live virus vaccines can change viral diversity and the consequences of such changes will not be evident for several generations.”

While many virus strains undergo a boom and bust cycle — they are present for a period of time and then die out — Poss notes that the use of live virus vaccines creates a persistent level of the vaccine strains in the global bird population.

Poultry farmers around the world vaccinate birds with vaccine made from one of two live strains of an avian virus that causes Newcastle Disease. While vaccines from the first strain are used mainly in Asia, the second strain is used in vaccines worldwide. Since the 1950s, vaccines derived from the two strains have helped poultry farmers avoid devastating economic losses.

To determine the impact of vaccination on the evolution of wild viruses, researchers analyzed the evolutionary history of 54 samples of full-length genome sequences of the avian paramyxovirus — the virus that causes Newcastle Disease — isolated from infected birds.

If all six genes that make up the paramyxovirus shared the same ancestor, Poss reasoned, the family trees of each gene would look the same. However, genes that are derived from a different strain would have family trees distinct from the other genes of that virus, a strong signature of recombination.

Statistical analysis of the gene sequences indicates that recombination occurred in at least five of the sampled genomes. Four of these five genomes contained gene sequences from one of the two vaccine strains.

Researchers next reconstructed the population history of the different viral strains. The strain from which the vaccine was derived showed a higher and more constant population size compared to other circulating strains.

“When viruses don’t change, it is typically a good thing,” Poss explained. “But as soon as they start to change, like the flu, we don’t know what the transmission and disease potential are going to be like from one year to another. So driving up viral diversity is not a good thing.”

Children with MS were 1.74 times more likely to have received a certain type of hepatitis B vaccine, called Engerix B®. Those children with MS developed symptoms three or more years after the vaccine.

Public release date: 25-Sep-2008 Re-Posted for Filing

Contact: Rachel Seroka
rseroka@aan.com
651-695-2738
American Academy of Neurology

Majority of children vaccinated against hepatitis B not at increased risk of MS

ST. PAUL, Minn. – The majority of children vaccinated against hepatitis B are not at an increased risk of developing multiple sclerosis (MS), according to a study to be published in the October 8, 2008, online issue of Neurology®, the medical journal of the American Academy of Neurology.

The study based in France involved 349 children with MS and 2,941 children without the disease. The children were all under the age of 16. A total of 24.4 percent of the children with MS were vaccinated for hepatitis B in the three years before the study, compared to 27.3 percent for the children without MS.

Although the study found that hepatitis B vaccination does not generally increase the risk of multiple sclerosis, the children with MS were 1.74 times more likely to have received a certain type of hepatitis B vaccine, called Engerix B®. Those children with MS developed symptoms three or more years after the vaccine. The risk was only found for this specific type of hepatitis B vaccine and not found for all vaccines against hepatitis B.

This association cannot be taken as confirmation that the vaccine caused MS. Further studies are needed to determine whether this is a causal relationship.

 

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The American Academy of Neurology, an association of more than 21,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as stroke, Alzheimer’s disease, epilepsy, Parkinson’s disease, and multiple sclerosis.

For more information about the American Academy of Neurology, visit www.aan.com.

Flu Vaccine offers no Protection in seniors

Respost 2008

Contact: Rebecca Hughes hughes.r@ghc.org 206-287-2055 Group Health Research Institute

Flu vaccine may not protect seniors well

Group Health study in Lancet finds no less risk of pneumonia with vaccine

SEATTLE—A Group Health study in the August 2 issue of The Lancet adds fuel to the growing controversy over how well the flu vaccine protects the elderly.

The study of more than 3,500 Group Health patients age 65󈟊 found no link between flu vaccination and risk of pneumonia during three flu seasons. “This suggests that the flu vaccine doesn’t protect seniors as much as has been thought,” said Michael L. Jackson, PhD, MPH, a postdoctoral fellow at the Group Health Center for Health Studies.

“Ours is by far the largest case-control study of flu vaccine in the elderly,” Jackson added. This kind of study compares “cases” with “controls.” The cases were patients with “community-acquired” pneumonia treated in a hospital or elsewhere. The controls were people matched to cases by sex and age, but with no pneumonia. Both groups were found to have similar rates of flu vaccination. All had intact immune systems and none lived in a nursing home.

Jackson and his colleagues carefully reviewed medical records to reveal details of seniors’ health and ability to do daily activities. “We tried to overcome the limits of previous studies done by others,” he explained. “Those studies may have overestimated the benefits of the flu vaccine in the elderly for various reasons.” For instance, those studies looked only at pneumonia cases treated in a hospital. They also included seniors who had immune problems, which limit potential benefit from vaccination. And they didn’t review medical records to get information on chronic diseases, such as heart or lung disease, which raise the risk of pneumonia.

Most importantly, those previous studies also failed to account for differences between healthier seniors and those who were “frail,” Jackson said. Frail seniors are older and have chronic  diseases and difficulty walking. “They are less likely than younger, healthier seniors to go out and get vaccinated—and more apt to develop pneumonia,” he said.

Pneumonia is a common and potentially life-threatening complication of the flu, Jackson said. But pneumonia can happen without the flu. “That’s why our study used a control time period, after flu vaccine became available but before each flu season actually started,” he said. During those pre-flu-season periods, people who had been vaccinated were much less likely to get pneumonia. Why? “Because those who got the vaccine happened to be healthier—not because the flu vaccine was protecting them from pneumonia caused by the flu, since it wasn’t present yet,” he explained.

“Despite our findings, and even though immune responses are known to decline with age, I still want my grandmother to keep getting the flu vaccine,” said Jackson. “The flu vaccine is safe. So it seems worth getting, even if it might lower the risk of pneumonia and death only slightly.”

His co-author Lisa A. Jackson, MD, MPH (no relation), a senior investigator at the Group Health Center for Health Studies, agreed. “People age 65 and older should still get yearly flu vaccines as usual,” she advised. But she said that researchers should work to understand better how well the current flu vaccines work in seniors—and to explore other options for controlling flu in the “old old.” Examples include bigger doses or stronger types of vaccines, and conducting randomized controlled trials comparing them.

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Other co-authors are Group Health’s Jennifer C. Nelson, PhD and William Barlow, PhD; Noel S. Weiss, MD, DrPH of the Fred Hutchinson Cancer Research Center and University of Washington; and Kathleen M. Neuzil, MD, MPH, of the Program for Appropriate Technology in Health (PATH), University of Washington, and the Group Health Center for Health Studies, all in Seattle.

A fellowship grant from the Group Health Foundation and internal funds from the Group Health Center for Health Studies funded this study.

Group Health Center for Health Studies

Founded in 1947, Group Health Cooperative is a Seattle-based, consumer-governed, nonprofit health care system that coordinates care and coverage. For 25 years, the Group Health Center for Health Studies has conducted research on preventing, diagnosing, and treating major health problems. Government and private research grants provide its main funding.

Please visit the virtual newsroom on our Web site, www.ghc.org under “Newsroom.”

Scientists develop fungus-fighting vaccine

Contact: Nickey Henry henryn@rockefeller.edu 212-327-8366 Journal of Experimental Medicine

A group of scientists in Italy have developed a vaccine with the potential to protect against fungal pathogens that commonly infect humans, according to a study by Torosantucci and colleagues in the September 5 issue of The Journal of Experimental Medicine.  Although these fungi pose little threat to people with healthy immune systems, they can cause fatal infections in those whose immune systems have been weakened by cancer treatments or post-transplant immunosuppressive therapies.  No anti-fungal vaccines are currently available.

The new vaccine was made of a sugar-like molecule called beta-glucan that is found on the cell wall of the fungus and that the fungus needs to grow and survive.  To induce a robust immune response to the vaccine, the group attached the relatively innocuous beta-glucan to a protein called diptheria toxin that is known to stimulate the immune system and has been used in other human vaccines.

The vaccine protected rodents from fatal fungal infections by triggering the production of anti-beta-glucan antibodies.  These antibodies stuck to the invading fungal cell wall and prevented the fungus from growing.  The authors now plan to test the vaccine in humans and hope the results are equally promising.

Reposted for Filing 2005

OHSU research suggests America may over-vaccinate

 

 

PORTLAND, Ore. –A new study published in the New England Journal of Medicine this week by Oregon Health & Science University researchers suggests that timelines for vaccinating and revaccinating Americans against disease should possibly be reevaluated and adjusted. The study shows that in many cases, the established duration of protective immunity for many vaccines is greatly underestimated. This means that people are getting booster shots when their immunity levels most likely do not require it. The results are published in the November 8 edition of the journal

 

“The goal of this study was to determine how long immunity could be maintained after infection or vaccination. We expected to see long-lived immunity following a viral infection and relatively short-lived immunity after vaccination, especially since this is the reasoning for requiring booster vaccinations. Surprisingly, we found that immunity following vaccination with tetanus and diphtheria was much more long-lived than anyone realized and that antibody responses following viral infections were essentially maintained for life,” explained Mark Slifka, Ph.D. Slifka serves as an associate scientist at the Vaccine and Gene Therapy Institute with joint appointments at the Oregon National Primate Research Center and the department of molecular microbiology and immunology in the OHSU School of Medicine.

 

The research also reconfirmed a previous finding by Slifka and his colleagues: that the duration of immunity after smallpox vaccination is much longer than previously thought. In that earlier study published in the journal Nature Medicine in 2003, these OHSU researchers observed surprisingly long-lived antiviral antibody responses but they were unable to measure the slow rate of decline. In this current study, they demonstrate that this type of immunity is maintained with a calculated half-life of 92 years – a number that is substantially longer than the estimate of only 3 to 5 years of immunity following vaccination that was previously proposed by experts at the Centers for Disease Control and Prevention.

 

“Another example is the tetanus vaccine,” said Slifka. “Doctors are told that vaccination is effective for a period of 10 years – but after that, people should be revaccinated. Based on our studies and the work of others, once a person has received their primary series of vaccinations they are likely to be protected for at least three decades. Indeed, other countries such as Sweden have changed their vaccination policies and doctors are advised to offer tetanus revaccination only once every 30 years.” Importantly, this has not resulted in any increase in the number of tetanus cases in Sweden and demonstrates first-hand that switching from the 10-year to 30-year policy is safe and effective. Taking this small step in vaccination scheduling could save hundreds of millions of dollars on health care here in the US.”

* Requested Repost

 

Vaccine tied to ‘superbug’ ear infection – Old Prevnar 2007 Historical Only

*Requested Repost From 2007 – Info is Historical

 

A vaccine that has dramatically curbed pneumonia and other serious illnesses in children is also having an unfortunate effect: promoting new superbugs that cause ear infections

On Monday, doctors reported discovering the first such germ that is resistant to all drugs approved to treat childhood ear infections. Nine toddlers in Rochester, N.Y., have had the bug and researchers say it may be turning up elsewhere, too.

Wyeth anticipated this and is testing a second-generation vaccine. But it is at least two years from reaching the market, and the new strains could become a public health problem in the meantime if they spread hard-to-treat infections through day care centers and schools.

It is a strain of strep bacteria not included in the pneumococcal vaccine, Wyeth’s Prevnar, which came on the market in 2000. It is recommended for children under age 2.

Prevnar, however, is losing its punch because strains not covered by the vaccine are filling the biological niche that the vaccine strains used to occupy, and they are causing disease.

One strain in particular, called 19A, is big trouble. A new subtype of it caused ear infections in the nine Rochester children, ages 6 months to 18 months, that were resistant to all pediatric medications, said Dr. Michael Pichichero, a microbiologist at the University of Rochester Medical Center.

The children had been unsuccessfully treated with two or more antibiotics, including high-dose amoxicillin and multiple shots of another drug. Many needed surgery to place ear tubes to drain the infection, and some recovered only after treatment with a newer, powerful antibiotic whose safety in children has not been established.

–Scientists from a drug company and two labs analyzed more than 21,000 bacterial samples from around the nation and found 19A increasing. Among children 2 and under, the portion of samples that were this strain rose to 15 percent in 2005-2006, from 4 percent in the previous three years.

–A British lab tracking respiratory infections in U.S. kids found that the 19A strain accounted for 40 percent of drug-resistant cases.

–University of Iowa researchers found 19A accounted for 35 percent of penicillin-resistant infections in 2004-05, compared with less than 2 percent the year before the new vaccine came out.

Live virus used in polio vaccine can evolve and infect, warns TAU researcher

Live virus used in polio vaccine can evolve and infect, warns TAU researcher

Health professionals and researchers across the globe believe they are on the verge of eradicating polio, a devastating virus which can lead to paralysis and death. Despite successful eradication in most countries, there are still four countries where the virus is considered endemic — and many more in which the virus still lurks.

Dr. Lester Shulman of Tel Aviv University‘s Sackler Faculty of Medicine and the Israeli Ministry of Health has spent years tracking isolated cases of live poliovirus infections, often discovered in countries that are supposedly polio-free. When the live-virus version of the vaccine, called Oral Polio Vaccine (OPV) evolves, he says, it can act like wild poliovirus and continue the threat of contagion.

Medical professionals widely believe that after the wild virus is eradicated, resources dedicated to polio immunization can be redirected. But this isn’t so, he says. He recommends that public health agencies take a three-pronged approach: Vaccination policies to maintain “herd immunity” (a 95 percent immunization rate for polio) should be maintained to prevent the spread of wild and evolved vaccine strains of the virus; environmental surveillance of sewage systems should continue; and a switch to Inactivated Polio Vaccine (IPV) instead of OPV should be implemented.

Dr. Shulman’s research was recently published in PLoS ONE. He has also been invited as an informal expert to the World Health Organization’s annual meeting on polio this fall.

A decade-long chase

While the eradication of polio is seemingly within reach, this is not the time to relax, Dr. Shulman warns. Most countries only investigate the possibility of poliovirus outbreaks when paralytic cases appear in the human population. But this doesn’t take into account a potential problem posed by the live virus vaccine. Over time, the vaccine can mutate, and even a 1 percent genomic change in the virus permits the virus to behave like a wild poliovirus. If a population isn’t sufficiently immunized, this spells trouble.

Israel is among the few countries that practice environmental surveillance for polio, beginning in 1989. Checking designated sites along sewage systems every month for evidence of the virus allows for early detection before there are paralytic cases. For the past decade, the researchers have been trying to trace the origin of the strain that infected two individuals in Central Israel. They tracked the strains to the sewage system, and have been working to pinpoint the origin. Fortunately, because Israel maintains herd immunity for the disease, the wider population has not been threatened.

Dr. Shulman says that in the lab, each strain of the virus can be identified from its genomic structure and traced back to the region from which it originated. “From the sequence of the genome, you can match it with known sequences reported by labs throughout the world,” he explains. For example, he and his colleagues traced a wild poliovirus discovered in sewage from the Gaza District to a village in Egypt.

New hope for curing persistent infections

Convinced by the efficacy of Israel’s environmental surveillance program, many other countries are starting to develop tracking programs of their own. As a result, they are finding evidence of vaccine-derived polio cases in humans. Paradoxically, Dr. Shulman sees a beacon of hope in these discoveries. As labs across the world report more cases, researchers gain a better understanding of how polioviruses establish persistent infections and can then develop effective measures to eliminate them.

The fellow researchers are now working to develop compounds that can effectively fight these rare cases of persistent poliovirus infections. So far, they have seen promising results, noting that the mutants strains have not become resistant to the drugs under investigation. But for now, Dr. Shulman recommends that health authorities continue immunization using inactivated vaccines (IPV) to keep their populations safe

* Reposted from Nov 2011. There will be a few repost, until the other studies are full transfered

Gene-swapping vaccines spawn lethal poultry virus – experts

Three vaccines used to prevent respiratory disease in chickens have swapped genes, producing two lethal new strains that have killed tens of thousands of fowl across two states in Australia, scientists reported on Friday.

The creation of the deadly new variant was only possible because the vaccines contained live viruses, even though they were weakened forms, said Joanne Devlin, lead author of the paper published in the journal Science.

Devlin and her team discovered how closely related the two new strains were with viruses in the vaccines after analysing their genes.

“What we found was the field viruses … were actually a mixture of the genomes from different vaccine viruses,” said Devlin, a lecturer at the University of Melbourne’s School of Veterinary Science. “They actually combined, mixed together.”

The viruses emerged in 2008, a year after Australia started using a European vaccine along with two very similar Australian vaccines to fight acute respiratory disease in poultry. The illness causes coughing, sneezing and breathing difficulties in birds, normally killing 5 percent of them.

The two new strains, however, were far more harmful, and since they were created have killed up to 17 percent of chicken flocks across Victoria and New South Wales, the two main chicken rearing states in Australia.

“What could have happened was one chicken was vaccinated with one vaccine and later was exposed to the other vaccine somehow, from nearby chickens,” Devlin said.

Agricultural authorities in Australia have been informed of the results of the study, and are considering how to prevent similar cross-overs happening again.

“Use of only one vaccine in a population of birds will prevent different viruses from combining,” Devlin said.

“Authorities are reviewing labels on vaccine to change the way vaccines are used and prevent different vaccines being used in one population.”