Aug 26, 2011
Pregnant women, obese more commonly prioritized globally for flu vaccine
Those placed in priority groups to receive seasonal or the 2009 pandemic flu vaccine vary broadly among countries, with pregnant women, obese patients, and healthcare workers (HCWs) becoming increasingly targeted, according to researchers who studied policies in 72 countries over the past several years. Scientists from the University of Hong Kong analyzed target groups in 33 countries for whom policies were accessible for seasonal flu vaccine in 2009 (Southern Hemisphere) and 2009-10, 72 countries for monovalent 2009 H1N1 vaccine, and 34 countries for seasonal 2010 and 2010-11 vaccines. They found that for seasonal 2009-10 vaccines, which were produced before the pandemic, 97% of nations placed the elderly in the priority group, followed by those with chronic conditions (91%), HCWs (70%), and nursing home residents (52%). Pregnant women were included in only 46% of plans, and the obese in only 3%. For the 2009 H1N1 vaccine, pregnant women, HCWs, and those with chronic illnesses were targeted in about 90% of plans. One-fifth to one-fourth targeted obese patients and close contacts. Compared with the seasonal 2009-10 vaccine, the elderly, nursing home residents, and close contacts were less commonly targeted. Priority groups for post-pandemic seasonal flu vaccine were similar to those for 2009-10 seasonal flu vaccine, except pregnant women, obese persons, HCWs, and close contacts were more commonly targeted. The elderly were most commonly prioritized (82%), followed by those with chronic illnesses (79%), pregnant women (57%), HCWs (50%), nursing home residents (39%), close contacts (36%), and the obese (25%).
Aug 26 BMC Infect Dis abstract
Almost century-old data show 1918 pandemic flu was moderately transmissible
A study of a previously unpublished large household survey conducted in Baltimore during the fall wave of the 1918 pandemic suggests that the virus was moderately transmissible, similar to the 2009 H1N1 virus, with few asymptomatic infections. The report, led by researchers at Imperial College London and Johns Hopkins University, appears in the September issue of the American Journal of Epidemiology. The team found the survey of 7,287 households in archives at Johns Hopkins. It had been led by Wade Hampton Frost, a pioneer in epidemiological field studies and modeling. In the new analysis of the data, the researchers used Frost's original models and modern ones that included more variables such as preexisting immunity and asymptomatic infections. They compared the data with estimates for seasonal and 2009 H1N1 flu.
Sep 1 Am J Epidemiol abstract
Hong Kong pigs produce recombinant H3N2-pH1N1 flu virus
Hong Kong's Centre for Food Safety announced today that 16 pig samples collected in June and July were found to contain a swine influenza H3N2 virus that had picked up some genes from the human 2009 H1N1 influenza virus. According to a 7th Space Interactive report, Malik Peiris, the Hong Kong University (HKU) expert in charge of Hong Kong's surveillance program, said it is unlikely the H3N2 virus poses a threat to human health or food safety. Peiris said, "Given the fact that the human swine influenza virus has spread worldwide in humans and pigs have also been infected by this virus, the recent finding is not a cause for surprise. HKU is conducting further tests to learn more about this particular strain." Hong Kong officials identified a swine-origin H1N1 virus early in 2010 that also contained genes from pandemic 2009 H1N1.
Aug 26 7th Space report
Gene study plots differences in human immune response to flu
In what is thought to be the most extensive investigation of human response to influenza exposure, researchers from the University of Michigan and Duke University have found gene expression patterns that provide clues about how disease progresses in symptomatic and asymptomatic people. As detailed in Public Library of Science (PLoS) Genetics, they exposed 17 healthy volunteers to influenza A (H3N2), and took peripheral blood samples 16 times over 132 hours. To identify gene expression patterns, they used a recognition tool called Bayes linear unmixing, which has previously been used to process satellite images of earth, according to a University of Michigan press release. They found a molecular signature that correlated with clinical disease and biomarkers that distinguished early from late infection phases and suggested that the findings could be used to identify new treatment targets and provide diagnostic assessment for seasonal and pandemic flu.
Aug 25 PLoS Genetics abstract
Aug 25 University of Michigan press release