Infectious Diseases News Brief - August 13, 2010

[Current Issue -Table of contents]

Genes For Meningitis Susceptibility And Resistance Revealed

Published in a leading journal this week, a large genome study of meningitis and septicaemia suggests genetic differences could be why some people are more susceptible and others naturally resistant to these diseases. The international study of over 6,000 people suggests that people who develop meningitis and septicaemia caused by meningococcal bacteria have gene variants that make their immune systems unable to defend effectively against the bacteria. In the first stage they compared the genomes of 475 people with the disease to 4,703 healthy controls and in the second stage they did two replication studies covering a total of 968 cases and 1,376 controls. The people involved in the studies were from the UK, Holland, Austria and Spain. The controls came from the Wellcome Trust Case Control Consortium. The researchers searched half a million genetic variants scattered across each participant's genome. By the end of the search and the replication studies, they found those participants who developed meningococcal meningitis had different snips in a number of genes involved in attacking and killing invading bacteria. The snips or gene variations they found to be most significant were in the genes for Factor H and Factor H-related proteins, which are involved in the complement system, which helps organize the immune response that recognizes and kills invading bacteria.

Source: Medical News Today 9 August 2010
http://www.medicalnewstoday.com/articles/197227.php

Clinical Trials In Asia, Africa Confirm Safety, Effectiveness Of Rotavirus Vaccine

Two studies published online Thursday in the Lancet show that the rotavirus vaccine is safe and effective at preventing much of the gastrointestinal illness in developing countries, where rotavirus kills more than 400,000 children under age 5 annually. Though rotavirus vaccines are now part of the regular schedule for infants in the United States and other developed countries the two studies show they would also be effective in places without sure supplies of clean water or medical care, where diarrhea is one of the major killers of young children. For the study conducted in Asia, researchers performed a randomized controlled trial on more than 2,000 infants ages 4-12 weeks. The children were randomly assigned to receive three oral doses of pentavalent rotavirus vaccine 2 mL or placebo at around 6 weeks, 10 weeks, and 14 weeks of age, in conjunction with routine infant vaccines including oral poliovirus vaccine.

Source: Medical News Today 9 August 2010
http://www.medicalnewstoday.com/articles/197196.php

Significant Drop In MRSA Infections In USA, Estimated 28% In Hospital And 17% Fall In Community Acquitted Infections

Experts from the CDC report that MRSA infections have dropped significantly in the USA over the last four years. Researchers examined data from 2005 through to the end of 2008 of nine American metropolitan areas. They reveal that health care-associated invasive methicillin-resistant Staphylococcus aureus (MRSA) infections fell among patients with infections that began in the community or in the hospital. All reports of laboratory-identified episodes of invasive (from a normally sterile body site, i.e., such as the bloodstream) MRSA infections were assessed and classified based on the setting of the positive culture and the presence or absence of health care exposures. Eighty-two per cent of the total infections, which were included in the analysis, came from health care-associated infections, such as hospital-onset and health care-associated community-onset. The evaluation revealed that there were: 21,503 cases of invasive MRSA infections for the years 2005 through 2008; 17,508 cases either hospital-onset or health care-associated community-onset; and most health care-associated infections (15,458 [88 percent]) involved a positive blood culture and were classified as a bloodstream infection (BSI).

Source: Medical News Today 11 August 2010
http://www.medicalnewstoday.com/articles/197517.php