FLU NEWS SCAN: H1N1 in pregnancy, avian flu seroprevalence, H5N1 in Egypt

Sep 16, 2011

Serious outcomes in pregnant Canadians with H1N1 lower than in other groups
An analysis of all known cases of pandemic 2009 H1N1 flu in pregnant Canadian women showed a lower incidence of severe outcomes compared with other H1N1 cases but an overrepresentation of indigenous women. The report, published today in Epidemiology and Infection, included 263 lab-confirmed 2009 H1N1 cases from Apr 12, 2009, through Apr 3, 2010, reported to the Public Health Agency of Canada. Those cases represented 3.2% of all Canadian H1N1 cases, which was about twice the level found in the previous three flu seasons. Of the 263 cases, 29 (11%) were admitted to an intensive care unit (ICU) and survived, and 4 women (1.5%), all in their third trimester, died. This compares with ICU rates of 14.8% among all H1N1 cases and 17.2% among women of reproductive age who had H1N1, and death rates were 5.1% and 3.9% in these two groups, respectively. Indigenous Canadians represented 16.2% of the cases of H1N1 in pregnancy but only 4.3% of the country's population of women of reproductive age.
Sep 16 Epidemiol Infect abstract

Thai villagers show seroprevalence to 3 avian flu strains
A study of villagers in a Thai province that has been home to multiple avian flu outbreaks in poultry found seroprevalence rates from 3.5% to 5.6% for three avian flu strains, but also found that contact with poultry was not associated with seroprevalence. A team of US, Thai, and Cambodian researchers studied 800 villagers from Kamphaeng Phet province (mean age, 49.6 years and 58% female), among whom about two-thirds had a lifetime exposure to poultry of at least 30 consecutive minutes. They found that 38 participants (4.7%) were seropositive to a low-pathogenic Hong Kong H9N2 avian flu strain, 45 (5.6%) were seropositive to A/Thailand/676/2005 H5N1, and 28 (3.5%) were seropositive to A/Thailand/384/2006 H5N1. (The researchers chose antibody titers of 1:10 or higher for seropositivity because of the low prevalence of elevated antibodies they found and because of onset infection dates.) Risk factors for H9N2 infection were male gender, lack of an indoor water source, and tobacco use, while for H5N1 they were advanced age, lack of an indoor water source, and chronic breathing problems. Poultry exposure was not associated with positive serologic findings for any of the strains.
Oct 15 Clin Infect Dis study

ECDC: Stronger vet measures needed in Egypt against H5N1
Veterinary measures to control H5N1 avian influenza may not be strong enough to monitor continuing outbreaks in Egyptian poultry, but so far there is no evidence that H5N1 infection patterns in humans have changed, the European Centre for Disease Prevention and Control (ECDC) said in a risk assessment report. It said continuing transmission of the virus in poultry and on to humans in Egypt over the past 5 years is worrisome, and if it emerges into a pandemic strain could affect Europe quickly. Current data, however, show no major changes in the human epidemiology of H5N1 in Egypt or that the virus has become more adaptable to humans. The ECDC said its Egyptian risk assessment grew out of its global H5N1 risk assessment in August following a UN Food and Agriculture Organization report that suggested H5N1 risks were changing.
Sep 15 ECDC press release
Sep 15 rapid risk assessment report

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