Rapid Pneumococcal Evolution in Response to Clinical Interventions
Nicholas J. Croucher et al.
Science 28 January 2011:
Vol. 331 no. 6016 pp. 430-434


With Sleight of DNA, Pneumonia Bacterium Dodges Vaccines
By SINDYA N. BHANOO
http://www.nytimes.com/2011/02/01/science/01obpneumonia.html

Researchers from seven countries have collaborated to analyze how a single strain of Streptococcus pneumoniae bacteria has morphed over 30 years and spread across the world, in an attempt to overcome the development of antibiotics and vaccines....

In looking at more than 240 samples, they found that since 1984, when the strain was first identified in Spain, it has turned over about three-quarters of its genome.

Over time, the bacteria mutated to better resist antibiotics and vaccines. The researchers found that it underwent both recombination, in which the DNA shuffles around, and base substitutions, in which individual nucleic acids in a DNA sequence change....

New superbug making kids sick despite vaccine

By Jordan Lite in 60-Second Science Blog

A new superbug that causes meningitis and pneumonia in kids has public health officials worried: Serotype 19A of the Streptococcus pneumoniae bacterium eludes most antibiotics and a vaccine intended to prevent infection. 

Rates of meningitis, pneumonia and bloodstream infections from the dangerous strain have increased from 2 in 100,000 children in 2001 to more than 10 per 100,000, the New York Times reports today. At the same time, life-threatening infections among the elderly have gone up fourfold, the newspaper notes. 

The eight-year-old Prevnar vaccine inoculates infants and toddlers against seven strains of the bacteria that caused 70 percent to 80 percent of pneumococcus infections in the '90s, and within two years of its 2000 introduction, rates of those illnesses had fallen by 80 percent in some places. But the four-shot series never protected against serotype 19A, and now its manufacturer, Wyeth, is racing to develop a next-gen shot against that and five additional strains, the company's head of vaccine research and development, Emilio Emini, told the Times. 

Health authorities said the vaccine isn't to blame for the rise in resistant strains of the bacteria. Still, the phenomenon suggests that Prevnar may have to be updated like the flu shot, the Pharmalot blog noted in a post last year about a surge in ear infections from serotype 19A. Scientists make new flu vaccine annually, based on the strains they guess will be most common in a given year.

http://www.scientificamerican.com/blog/60-second-science/post.cfm?id=new-superbug-making-kids-sick-despi-2008-10-14

Serious Lung Infections in Children Jump After Introduction of Pneumococcus Vaccine


By UC Davis Children's Hospital
Jan 11, 2010 - 4:34:16 PM

http://www.healthnewsdigest.com/news/Children_s_Health_200/Serious_Lung_Infections_in_Children_Jump_After_Introduction_of_Pneumococcus_Vaccine.shtml


A comprehensive national study by UC Davis researchers has found that the introduction of an early childhood vaccine for bacterial pneumonia nearly a decade ago has decreased the incidence of pneumonia, but the drop was accompanied by a dramatic increase in the incidence of a serious and sometimes life-threatening complication. The researchers conjecture that the doubling of the incidence of the complication, which causes pockets of purulence, or pus, around the lungs, may partly be the result of the vaccine eliminating certain types of pneumococcus, creating the opportunity for other bacteria to take its place.

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