NEWS SCAN: H7N3 in Mexico, global flu activity, synthetic FMD vaccine

Apr 2, 2013

H7N3 outbreaks, culling in Mexico have killed almost 4 million poultry
Outbreaks of H7N3 avian flu over the past 5 weeks have led to almost 4 million poultry deaths in Guanajuato and Jalisco states, according to a translated media report yesterday from ProMED Mail, the online reporting system of the International Society for Infectious Diseases. Official figures indicate that 1,984,000 broilers, 847,000 breeders, and 918,221 laying hens have died, for a total of 3,749,221, on 52 farms and in four backyard flocks. In addition, more than 131 million vaccine doses have been administered to flocks in Jalisco, Aguascalientes, and Guanajuato states, as well as in nine additional "federal entities," the report said. So far, 117 of 158 farms in Guanajuato have already been inspected by officials, and H7N3 was found on 25 of them, as well as in 2 of 195 backyard flocks. In Jalisco, 27 of 535 farms and 2 of 135 backyard flocks tested positive. The outbreaks have cost farmers $32 million. Mexico culled about 3.8 million birds last year to help prevent disease spread after mulitple H7N3 outbreaks in Jalisco.
Apr 1 PROMed Mail post

WHO: Flu activity decreasing in most parts of the world
Flu activity in the Northern Hemisphere over the past 2 weeks declined and was still at interseasonal levels in the Southern Hemisphere, the World Health Organization (WHO) said in its latest surveillance update today. In temperate parts of Asia, flu activity decreased, except in Mongolia, which reported sustained flu levels that were still at expected seasonal levels. Some countries in Europe, as well as the Canada and the United States, are reporting that influenza B is the predominant strain, though at the global level, influenza A viruses dominated, with the 2009 H1N1 virus accounting for about 58% of the subtyped samples. In countries that perform antiviral resistance testing, a few viruses have shown reduced susceptibility to oseltamivir. Other lab studies suggest that circulating viruses are antigenically similar to the ones included in the current season's Northern Hemisphere flu vaccine.
Apr 2 WHO influenza update
Apr 2 WHO virologic update

Study shows synthetic FMD vaccine offers good protection
UK researchers have produced a synthetic vaccine for foot-and-mouth disease (FMD) that proved effective in cattle, is safer to make than standard FMD vaccines, and does not require cold storage, according to a study in PLoS Pathogens. The vaccine is made up of tiny protein shells, or capsids, for triggering an immune response, and therefore doesn't require growing live viruses. The capsids were engineered to be more stable, "making the vaccine much easier to store and reducing the need for a cold chain," according to a news release from the UK Biotechnology and Biological Sciences Research Council (BBSRC), a funder of the study. Vaccinated cattle showed sustained virus neutralization titers and protection from challenge 34 weeks post-vaccination. Author David Stuart, PhD, said in the release, "What we have achieved here is close to the holy grail of foot-and-mouth vaccines. Unlike the traditional vaccines, there is no chance that the empty shell vaccine could revert to an infectious form. This work will have a broad and enduring impact on vaccine development."
Mar 27 PLoS Pathog study
Mar 27 BBSRC news release

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