Zinc greatly protects against bacterial pneumonia

Zinc greatly protects against bacterial pneumonia

Zinc greatly protects against bacterial pneumonia

They found that mice with lower zinc intake succumbed to infection up to three times faster because their immune systems had insufficient zinc to aid in killing the bacteria.

Bart A. Eijkelkamp, Jacqueline R. Morey, Stephanie L. Neville, Aimee Tan, Victoria G. Pederick, Nerida Cole, Prashina P. Singh, Cheryl-Lynn Y. Ong, Raquel Gonzalez de Vega, David Clases, Bliss A. Cunningham, Catherine E. Hughes, Iain Comerford, Erin B. Brazel, Jonathan J. Whittall, Charles D. Plumptre, Shaun R. McColl, James C. Paton, Alastair G. McEwan, Philip A. Doble, Christopher A. McDevitt. Dietary zinc and the control of Streptococcus pneumoniae infection. PLOS Pathogens, 2019; 15 (8): e1007957 DOI: 10.1371/journal.ppat.1007957

#zinc #pneumonia # Streptococcuspneumoniae

https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1007957

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”

How zinc starves lethal bacteria to stop infection

Contact: Dr Christopher McDevitt christopher.mcdevitt@adelaide.edu.au 61-449-823-946 University of Adelaide

Australian researchers have found that zinc can ‘starve’ one of the world’s most deadly bacteria by preventing its uptake of an essential metal.

The finding, by infectious disease researchers at the University of Adelaide and The University of Queensland, opens the way for further work to design antibacterial agents in the fight against Streptococcus pneumoniae.

Streptococcus pneumoniae is responsible for more than one million deaths a year, killing children, the elderly and other vulnerable people by causing pneumonia, meningitis, and other serious infectious diseases.

Published today in the journal Nature Chemical Biology, the researchers describe how zinc “jams shut” a protein transporter in the bacteria so that it cannot take up manganese, an essential metal that Streptococcus pneumoniae needs to be able to invade and cause disease in humans.

“It’s long been known that zinc plays an important role in the body’s ability to protect against bacterial infection, but this is the first time anyone has been able to show how zinc actually blocks an essential pathway causing the bacteria to starve,” says project leader Dr Christopher McDevitt, Research Fellow in the University of Adelaide’s Research Centre for Infectious Diseases.

“This work spans fields from chemistry and biochemistry to microbiology and immunology to see, at an atomic level of detail, how this transport protein is responsible for keeping the bacteria alive by scavenging one essential metal (manganese), but at the same time also makes the bacteria vulnerable to being killed by another metal (zinc),” says Professor Bostjan Kobe, Professor of Structural Biology at The University of Queensland.

The study reveals that the bacterial transporter (PsaBCA) uses a ‘spring-hammer’ mechanism to bind the metals. The difference in size between the two metals, manganese and zinc, causes the transporter to bind them in different ways. The smaller size of zinc means that when it binds to the transporter, the mechanism closes too tightly around the zinc, causing an essential spring in the protein to unwind too far, jamming it shut and blocking the transporter from being able to take up manganese.

“Without manganese, these bacteria can easily be cleared by the immune system,” says Dr McDevitt. “For the first time, we understand how these types of transporters function. With this new information we can start to design the next generation of antibacterial agents to target and block these essential transporters.”

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The research has been funded by the Australian Research Council and the National Health and Medical Research Council.

Media Contact:

Dr Christopher McDevitt Research Fellow Research Centre for Infectious Diseases School of Molecular and Biomedical Science The University of Adelaide Mobile: +61 449 823 946 christopher.mcdevitt@adelaide.edu.au

Professor Bostjan Kobe Professor of Structural Biology Australian Infectious Diseases Research Centre School of Chemistry & Molecular Biosciences The University of Queensland Phone : +61 7 3365 2132 b.kobe@uq.edu.au

Robyn Mills Media Officer The University of Adelaide Phone: +61 8 8313 6341 Mobile: +61 410 689 084 robyn.mills@

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

 2010 study posted for filing

Contact: Elisabeth A. M. Sanders, M.D., Ph.D. l.sanders@umcutrecht.nl JAMA and Archives Journals

This release is also available in Chinese on EurekAlert! Chinese.

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.

“A rapid increase in the presence of pneumococcal serotype 19A strains that are often multiresistant to antibiotics has been observed over the last decade. In the United States, serotype 19A is now the leading causative pneumococcal serotype of invasive and respiratory pneumococcal disease and the most frequently observed serotype in nasopharyngeal carriage. In the United States and other countries, the increase in serotype 19A disease was associated in time with the widespread implementation of PCV-7 in routine infant immunization programs,” according to background information in the article. “Because spontaneous fluctuations in time and antibiotic selective pressure may have induced this serotype 19A increase, controlled studies are needed to assess the role of PCV-7.”

Elske J. M. van Gils, M.D., of University Medical Center Utrecht, the Netherlands, and colleagues examined the association between PCV-7 vaccination and nasopharyngeal acquisition of serotype 19A pneumococci in 1,003 healthy newborns, with follow-up to the age of 24 months in the Netherlands, which has low antibiotic resistance rates. The study was conducted before widespread PCV-7 implementation in infants, between July 2005 and February 2008. Nasopharyngeal swabs were obtained at the age of 6 weeks and at 6, 12, 18, and 24 months. Infants were randomly assigned to receive 2 doses of PCV-7 at 2 and 4 months; 2 + 1 doses of PCV-7 at 2, 4, and 11 months; or no dosage (unvaccinated control group).

Nine hundred forty-eight children completed the study. Fifty-four nasopharyngeal serotype 19A carriage isolates from 318 in the 2-dose group, 66 isolates from 327 in the 2 + 1-dose group, and 33 isolates from 303 in the unvaccinated group were collected from 6 weeks through 24 months. “At 24 months and after having completed the vaccine series, the cumulative proportion of participants with acquisition of a new serotype 19A clone in the 2 +1-dose group was 16.2 percent (53 of 327) vs. 9.2 percent (28 of 303) in the unvaccinated control group. The cumulative proportion in the 2-dose group was also higher than in the unvaccinated group but did not reach statistical significance (13.2 percent; 42 of 318 children),” the authors write.

The proportion of children with new 19A acquisition who had used antibiotics in the last 6 months (18.7 percent) did not differ among groups.

“In addition to the contributing role of antibiotic selective pressure as previously described by others, we now have demonstrated, to our knowledge for the first time, the facilitating role of PCV-7 in nasopharyngeal acquisition of serotype 19A. In view of the proven disease potential of serotype 19A for otitis media and invasive pneumococcal disease and the observed association with antibiotic resistance, vaccines of broader coverage including protection against serotype 19A may further aid to pneumococcal disease prevention. However, we need to be aware that other serotypes with similar characteristics and disease potential may be the next in line to proliferate and therefore pneumococcal surveillance remains important after introduction of expanded pneumococcal conjugate vaccines,” the researchers conclude.

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(JAMA. 2010;304[10]:1099-1106. Available pre-embargo to the media at www.jamamedia.org)

Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Pneumococcal vaccine does not appear to protect against pneumonia: ” a systematic review and meta-analysis, looked at 22 clinical trials, reviews and meta-analyses and more than 100,000 participants “

2009 study posted for filing

Contact: Kim Barnhardt
kim.barnhardt@cmaj.ca
613-731-8610 x2224
Canadian Medical Association Journal

Commonly used pneumococcal polysaccharide vaccines do not appear to be effective for preventing pneumonia, found a study by a team of researchers from Switzerland and the United Kingdom http://www.cmaj.ca/press/pg48.pdf.

In many industrialized countries, polysaccharide pneumococcal vaccines (PPVs) are currently recommended to help prevent pneumococcal disease in people aged 65 and over and for younger people with increased risk due to conditions like HIV. Studies have shown conflicting results regarding the efficacy of PPV.

The study, a systematic review and meta-analysis, looked at 22 clinical trials, reviews and meta-analyses and more than 100,000 participants from countries in North America as well as India, Africa, Latin America and the Caribbean. Unlike other similar studies the authors examined the reasons why different clinical trials produced different results. They found that the quality of the studies substantially affected the results. When only high quality trials were included, there was no evidence that PPVs could prevent pneumonia. The study adds to the ongoing debate around effectiveness of the vaccine.

“Policy makers may therefore wish to reconsider their current recommendations for PPV, especially where routine pneumococcal conjugate immunization has been introduced,” conclude Dr. Matthias Egger from the University of Bern, Switzerland and coauthors.

However, in a related commentary http://www.cmaj.ca/press/pg18.pdf, Dr. Ross Andrews and coauthor from the Menzies School of Health Research, Darwin, Australia state that the researchers’ conclusions exceed the evidence presented. They caution that there should be no change in vaccine policy in countries that recommend PPV to prevent invasive pneumococcal disease

Pneumococcal disease rates down significantly post-vaccine: But One of the non-vaccine strains, 19A showed an increase of 264%

Contact: Jim Sliwa jsliwa@asmusa.org 202-942-9297 American Society for Microbiology

Pneumococcal disease rates down significantly post-vaccine

Since the approval of a vaccine against pneumococcal bacteria for young children in 2000, rates of invasive pneumococcal disease (IPD) are down significantly in all age groups, while rates of IPD caused by non-vaccine strains are modestly on the rise.  Researchers from the Centers for Disease Control and Prevention (CDC) report their results today (March 18) at the 2008 International Conference on Emerging Infectious Diseases in Atlanta, Georgia.

“This vaccine is continuing to provide a very substantial public health impact 6 years after its introduction.  We estimate that between 2001 and 2006, 170,000 cases and 9,800 deaths were prevented as a result of this vaccine,” says Matthew Moore of the CDC, a lead researcher on the study.

Streptococcus pneumoniae, also called pneumococcus, is one of the most common causes of bacterial pneumonia and deadly bloodstream infections in the United States. It can also cause bacterial meningitis in children and adults.  In its less severe forms it commonly causes ear infections.  Pneumococcus bacteria can be found colonizing many people’s noses without causing infection.  Why it suddenly invades the body and causes disease is unknown.

A vaccine against pneumococcal disease has been available for adults and children over 2 years of age since the 1980s, but in 2000 a new vaccine, known as PCV7, was approved by the FDA for children under 5 years of age.

The CDC has been tracking the incidence of IPD, the most severe form of the disease – defined as meningitis or a bloodstream infection, which can include some cases of pneumonia – since the introduction of the vaccine.  Moore and his colleagues compared rates of IPD in 2006 with reported rates for 1998-1999, just before PCV7 was introduced.

The researchers found a significant decline in IPD rates for all age groups (-78%, under 5 years; -38%, 5-17 years; -39%, 18-49 years; -14%, 50-64 years; -32%, 65-79 years; and -42%, 80 years and older) with even greater declines in IPD caused by those strains included in the PCV7 vaccine.  The incidence of IPD caused by strains not included in the vaccine rose by 40%.  One of the non-vaccine strains, 19A showed an increase of 264%, but Moore cautions that because these strains were relatively uncommon before the introduction of the vaccine, the increase in actual numbers is still small.

“PCV continues to provide impressive public health benefits after introduction.  Disease caused by non-PCV7 serotypes, especially 19A, is emerging and accounts for nearly all IPD.  Newer conjugate vaccines targeting more serotypes are needed to further reduce IPD,” says Moore.

The introduction of PCV7 may have also helped solve an enduring mystery associated with IPD.  The incidence of the disease is seasonal with rates running 5 times higher in the winter, but there is also a sharp but unexplained spike that occurs annually in older adults during the weeks around January 1.

Nicholas Walter of the CDC and his colleagues analyzed 11 years worth of IPD surveillance data and noticed that after the introduction of PCV7 the spikes were much less severe.  Since PCV7 is used in children, they had to figure that into the equation somehow.  Based on the data, Walter and his colleagues now believe the annual spike may be the result of older adults being exposed to colonized children when families get together for the winter holidays.

“Timing of the spikes and the predominance of older adults suggest the spikes may be related to older adults’ increased exposure to young children around the winter holidays,” says Walter, who also presented his data at the meeting.  The observation that spikes diminished after introduction of PCV7 gives further indication that vaccination of children limits disease not only in children, but also in adults.  Many of these infections may be preventable with pneumococcal polysaccharide vaccine, which targets 23 different serotypes and is recommended for all adults 65 years of age and older.

 

Resposted at Request 2008 Data

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The International Conference on Emerging Infectious Diseases is organized by the Centers for Disease Control and Prevention (CDC), the American Society for Microbiology, the Council of State and Territorial Epidemiologists, the Association of Public Health Laboratories and the World Health Organization.  More information on the meeting can be found online at www.iceid.org.