Featured Research

from universities, journals, and other organizations

Vaccine against pneumococcal infections has led to widespread reduction in serious disease

Date:
September 24, 2013
Source:
Public Library of Science
Summary:
Vaccination with the pneumococcal conjugate vaccine-7 [PCV7 -- a vaccine that covers 7 strains (serotypes) of Streptococcus pneumoniae is linked to overall decreases in the rate of serious infections caused by this bacterium, such as pneumonia and meningitis, referred to as invasive pneumococcal disease (IPD), but small increases in IPD caused by serotypes of Streptococcus pneumoniae not covered by the vaccine, according to a new study.

Vaccination with the pneumococcal conjugate vaccine-7 [PCV7 -- a vaccine that covers 7 strains (serotypes) of Streptococcus pneumoniae] is linked to overall decreases in the rate of serious infections caused by this bacterium, such as pneumonia and meningitis, referred to as invasive pneumococcal disease (IPD)], but small increases in IPD caused by serotypes of Streptococcus pneumoniae not covered by the vaccine ( referred to as non-vaccine type IPD), according to a study published in PLOS Medicine this week.

The results of this study, led by Daniel Feikin, Matthew Moore, and their colleagues from Johns Hopkins School of Public Health and the Centers for Disease Control and Prevention, USA, are important as they suggest rapid and sustained reductions in pneumococcal disease after vaccine introduction. The study does show that serotypes causing IPD covered by PCV-7 have been partially replaced by types not covered by PCV-7 (a phenomenon referred to as serotype replacement), which has implications for the surveillance of newer pneumococcal conjugate vaccines, such as PCV10 and PCV13, which cover more serotypes.

The authors combined IPD surveillance information from multiple countries to estimate changes in IPD rates before and after PCV7 introduction. For children aged under 5 years, the authors found that the overall number of observed cases of IPD in the first year after the introduction of PCV7 was about half the expected number; this reduction in the number of IPD cases remained relatively stable over 7 years. Among adults, the authors observed smaller, more variable decreases in overall IPD. Notably, the rate of IPD caused by vaccine serotypes decreased every year, but the rate of IPD caused by non-vaccine serotypes increased annually, which was likely to be the result of serotype replacement.

However, these findings have several limitations: PCV7 is no longer made and so extrapolation of these results to newer PCV10 and PCV13 formulations should be done cautiously. Moreover, because the surveillance data used in this study mainly came from high-income countries, these findings may not be generalizable to low-income countries, in which pneumococcal disease is a major problem.

The authors say: "The most important public health implication of our analysis was that decreases in overall IPD rates in children -- the group targeted for PCV7 vaccination -- occurred quickly and were sustained after vaccine introduction despite increases in [non-vaccine serotype] rates."

They continue: "Optimizing surveillance data that allows for valid interpretations of the vaccine effect on disease is essential for sound policy decisions."


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Feikin DR, Kagucia EW, Loo JD, Link-Gelles R, Puhan MA, et al. Serotype-Specific Changes in Invasive Pneumococcal Disease after Pneumococcal Conjugate Vaccine Introduction: A Pooled Analysis of Multiple Surveillance Sites. PLoS Med, 2013 DOI: 10.1371/journal.pmed.1001517

Cite This Page:

Public Library of Science. "Vaccine against pneumococcal infections has led to widespread reduction in serious disease." ScienceDaily. ScienceDaily, 24 September 2013. <www.sciencedaily.com/releases/2013/09/130924174329.htm>.
Public Library of Science. (2013, September 24). Vaccine against pneumococcal infections has led to widespread reduction in serious disease. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2013/09/130924174329.htm
Public Library of Science. "Vaccine against pneumococcal infections has led to widespread reduction in serious disease." ScienceDaily. www.sciencedaily.com/releases/2013/09/130924174329.htm (accessed July 22, 2014).

Share This




More Health & Medicine News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins