NEWS SCAN: Flu vaccines compared, flu in Hong Kong, foodborne outbreak updates

Mar 31, 2010

Different immune responses for different flu vaccine formulas
The open question of why different flu-vaccine formulas produce better immunity than others, and how that might be improved, may be partially answered by a mouse study published today in Science Translational Medicine. Researchers from three Japanese universities administered split-virus, attenuated live-virus, and inactivated whole-virus flu vaccines based on H1N1 to several varieties of knock-out mice and analyzed the complex immunological mechanisms that each invoked. The keys to the mice's immune responses were revealed to be both recognition of the virus by a particular receptor (toll-like receptor 7 or TLR7) and activation of a category of innate immune cells (plasmacytoid dendritic cells or pDCs). Both were involved in immune reaction to the killed whole-virus vaccine. The pDCs, though, were not activated by attenuated live-virus vaccine, and the split-virus vaccine was not recognized by the toll-like receptor. However, the split-virus vaccine did evoke an immune response in blood from humans who had already been exposed to H1N1 flu. That response, the authors said, suggests that pDCs play a role in vaccine priming, and thus that designing adjuvants to evoke this process could improve the efficacy of flu vaccines.
Mar 31 Sci Transl Med study abstract

Facing rise in seasonal flu, Hong Kong extends vaccinations
Because of an increase in seasonal influenza activity, the Hong Kong Department of Health is extending its seasonal flu vaccination programs until the end of April. In a statement yesterday, the department said there has been a steady increase in the number of flu viruses detections, with the H1N1 pandemic virus and influenza B predominating. Medical visits for flu-like illness and institutional outbreaks of flu-like illness also have been on the rise, the statement said. The department's three vaccination programs, which target different demographic groups, will be reviewed at the end of April to determine if they should continue further. A total of 504,506 doses of seasonal flu vaccine have been given since the program started in October.
Mar 30 Hong Kong press release

Illness count grows in raw-milk campylobacteriosis outbreak
State health departments have reported four more campylobacteriosis illnesses linked to contaminated raw milk from an Indiana farm, raising the number of cases to 16. Since Feb 26, when the US Food and Drug Administration (FDA) first warned consumers about contaminated milk that had sickened 12 Michigan residents, Indiana officials said they have detected three related illnesses, and the Kalamazoo (Mich.) Gazette, citing Illinois authorities, yesterday reported that Illinois has detected one case. Meanwhile, Michigan's Department of Community Health (MDCH) said 12 more patients were being tested to determine if their illnesses are linked to the outbreak, the Niles (Mich.) Daily Star reported today. The source of the contaminated milk is Forest Grove Dairy in Middlebury, Ind., which distributed its milk to a "cow share" program operated by Family Farm Cooperative in Vandalia, Mich., according to the MDCH. Illinois officials said the same farm cooperative has delivered suspect milk to several locations in Illinois, including Des Plaines, Downers Grove, Elgin, and Chicago. Symptoms of campylobacteriosis include diarrhea, abdominal pain, and fever. Public health officials have long warned of raw-milk hazards, and since1987 the FDA has required pasteurization of milk for human consumption for interstate commerce.
Mar 26 Indiana State Department of Health press release
Mar 30 Kalamazoo Gazette story
Mar 19 MDCH statement
Mar 24 Illinois Department of Public Health press release

List of recalls in Salmonella outbreak gets longer
The FDA yesterday released a considerably longer list of companies that have recalled products containing potentially contaminated pepper in connection with a nationwide Salmonella Montevideo outbreak. The FDA update shows that 14 companies have issued 16 recall announcements, involving a wide range of products, such as restaurant spice packets, seasoning mixes for cooking, trail mix, and cashews. The previous FDA update on Mar 17 listed five companies. The 14 firms are in addition to Daniele Inc., maker of salami products that were linked to the outbreak. The outbreak investigation led to the detection of Salmonella in black and red pepper that Daniele used in its products and to pepper recalls by Wholesome Spice Co. and Mincing Overseas Spice Co., which supplied pepper to Daniele. The additional recalls are by companies that sold products containing pepper bought from Wholesome Spice or Mincing Overseas Spice. The case count in the outbreak remains at 252 illnesses in 44 states and Washington, DC, according to the latest report (Mar 17) from the Centers for Disease Control and Prevention (CDC).
CDC outbreak update page

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