May 14, 2010
FDA clears rotavirus vaccines for use despite viral contamination
The porcine circovirus (PCV1 and PCV2) found in Rotarix and RotaTeq vaccines does not represent a threat to the health of recipients, and both vaccines should continue to be used, the Food and Drug Administration (FDA) ruled today. DNA from PCV1 was found Mar 22 in Rotarix, made by GlaxoSmithKline Biologicals Inc., and the vaccine was temporarily suspended from sale. DNA from PCV1 and PCV2 was found May 6 in Rotateq, made by Merck & Co. Inc.. The agency's Vaccines and Related Biological Products Advisory Committee (VRBPAC) met May 7 to review evidence from the manufacturers, the FDA's own laboratories, and the scientific literature. The committee concluded that the vaccines have a known benefit due to the clinical experience of millions of recipients, whereas any health risk from the viral fragments remains hypothetical. The decision clears Rotarix to be put back into use; RotaTeq was never suspended. However, clinicians should inform parents of the viruses' presence in the vaccines, and package information will be updated, the FDA said.
May 14 FDA updated recommendations
H5N1 hits Laotian poultry farm
Animal health officials in Laos today reported that the H5N1 avian influenza virus struck a poultry farm in Vientiane, the country's capital, according to a report to the World Organization for Animal Health (OIE). The outbreak killed 44 of the farm's 1,004 susceptible layer chickens. The birds started showing symptoms on Apr 27. Mortality dramatically increased from May 1 through May 5. The remaining birds were culled to control the spread of the virus, and authorities disinfected the premises and are conducting surveillance in a 5-km radius around the farm. The source of the outbreak has not been identified. The outbreak is the country's first in more than a year.
May 14 OIE report
Chickenpox outbreak confirmed in southwest Florida
Fort Myers and Lee County, Fla., have recorded 41 cases of chickenpox since February in what officials believe is a widely distributed outbreak linked to incomplete vaccinations. The cases are not limited to one school or one section of the county, though most children in the outbreak are in elementary school, according to a press release from the Florida Department of Health. Most of the children who have been diagnosed had received one dose of varicella vaccine, which is required when children enter school. However, according to the Centers for Disease Control and Prevention, two doses by 3 years of age are needed to establish full protection. Lee County recorded only 12 cases of chickenpox in 2008 and 15 in 2009, according to the North Fort Myers Neighbor.
May 11 Florida Department of Health press release
May 13 North Fort Myers Neighbor story
Japanese foot-and-mouth epidemic largest in a decade
The government of Japan has ordered the killing of almost 74,000 pigs and 6,600 cattle in hopes of containing the largest outbreak of highly contagious foot-and-mouth disease the nation has seen in 10 years, Bloomberg Businessweek reported. The cull, which is so far limited to Miyakazi Prefecture on the country's southern tip, accounts for 0.7% of national stocks of pigs and 0.1% of cattle. Outbreaks on 53 farm properties have been recorded since May 6 and local quarantines have been imposed, according to the OIE.
Listeria invades cells with protein two-step
To cross the epithelial barrier of the intestine and begin an infection, Listeria monocytogenes deploys two proteins that sequentially exploit a precise moment in epithelial-cell detachment, Stanford University researchers report in Public Library of Science (PLoS) Pathogens. Building on earlier work, the group determined that the bacterium uses one protein, Internalin A, to attach to epithelial molecules that are exposed only at a particular moment when cells at the tip of villi die and are shed. It then uses a second protein, Internalin B, that stimulates uptake of cell-surface molecules, including the one to which the first protein adhered.
May 13 PLoS Pathog paper