H1N1 NEWS SCAN: Low activity, structural basis for immunity, heart damage, monitoring Malaysia

WHO: H1N1 activity low in most countries
Circulation of the 2009 H1N1 pandemic virus persists only in tropical zones of the Americas, Africa, and Southeast Asia, the World Health Organization (WHO) reported today. B strains of seasonal flu are circulating in East Asia, along with sporadic seasonal A/H3N2 flu in Asia, Eastern Europe, and Eastern Africa; the most recent H3N2 reports were in Indonesia and Tanzania. A few seasonal H1N1 viruses, not the pandemic strain, were recorded last week in the Russian Federation and Northern China.
http://www.who.int/csr/don/2010_04_16/en/index.html
Apr 16 WHO update

CDC: US H1N1 activity still declining
Visits to doctors, lab-confirmed hospitalizations, and the proportion of deaths attributed to pneumonia and influenza all declined in the United States last week, the Centers for Disease Control and Prevention (CDC) reported today. However, 3 pediatric deaths were reported in the last week. One report was from a previous season, but 2 were from the current flu season, of which one was due to the 2009 H1N1 strain and the other to an influenza A strain that was not typed further.
http://www.cdc.gov/h1n1flu/update.htm/?date=041610
Apr 16 CDC update

Structural analysis confirms 1918, 2009 pandemic links
Structural analysis of the hemagglutinin of the 2009 H1N1 pandemic flu virus, and comparison of the structure with the recovered 1918 pandemic flu virus, reveals a shared epitope in both viruses, US researchers report today in Science. That antigenic similarity may explain repeated observations over the past year that those old enough to have been exposed to descendants of the 1918 virus possess some degree of protection against the 2009 strain.
http://www.sciencemag.org/cgi/content/abstract/328/5976/357
Apr 16 Science abstract

H1N1 virus found to damage heart
A previously healthy 11-year-old girl died of heart failure, caused by compression of the heart by fluid in its outer sac, that appears to have been caused by H1N1 flu infection. Italian researchers report in the Journal of Clinical Microbiology that H1N1 viral sequences were found in the girl's heart tissue and pericardial fluid, suggesting direct damage by the flu virus. They warn that myopericarditis may be an underappreciated result of H1N1 infection.
http://jcm.asm.org/cgi/content/abstract/JCM.00418-10v1
Apr 14 J Clin Microbiol abstract

Malaysia orders school monitoring for H1N1
Malaysia's Education Ministry has directed school principals in the country to monitor student bodies for influenza-like illness and to immediately isolate any students who may be suffering from novel H1N1 flu. Eleven new clusters of illness have been reported by the Health Ministry. The Education Ministry wishes to preserve school closures as a last resort, The Star of Malaysia reported today.
http://thestar.com.my/news/story.asp?file=/2010/4/16/nation/6064345&sec=nation
Apr 16 Star article

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