NEWS SCAN: Global H1N1 patterns, flu-strain predictions, antiviral mask, paid sick leave, H9N2-H1N1 reassortant, DRC cholera spread

Jul 6, 2011

Report shows global patterns for severe 2008 H1N1 infections
In the most comprehensive overview of severe 2009 H1N1 influenza patterns so far, a World Health Organization (WHO) working group reported yesterday that young children were more likely than other groups to be hospitalized from their infections, and though illnesses were less frequent in seniors, they were more likely to die from their infections. The study includes health ministry data on hospitalizations, intensive care unit admissions, and deaths collected from April 2009 to January 2010 from 18 countries and Hong Kong. The group found that the proportion of patients with one or more risk factors increased by severity level. When the researchers looked at individual risk factors, they found that the proportion also increased by severity level for all conditions except for asthma, pregnancy, and obesity. Pregnant women were seven times more likely than the general population to be hospitalized and twice as likely to die, which the group said could show that doctors had a lower threshold for admitting and aggressively treating pregnant women. Morbid obesity also stood out as a risk factor, with a proportion that increased by severity level. Indigenous populations in Australia, Canada, and New Zealand had a higher burden of disease, but not Mexico or Thailand. Researchers concluded that concerns about high-risk groups during the pandemic were justified and that improved surveillance can help track differences between countries.
Jul 5 PLoS Med study

Early-season strains may foretell flu-strain dominance
Using mathematical modeling, researchers may be able to predict how influenza strains will behave throughout a flu season based on which strains are circulating early in the season. Writing in PLoS Medicine, researchers from Harvard and the National Institutes of Health studied surveillance data from the Centers for Disease Control and Prevention on strains of influenza A/H3N2, A/H1N1, and B from 1997 to 2009. They found that early-season prevalence of a particular strain predicted its higher prevalence later to the detriment of the other two strains. They then devised a statistical algorithm that accurately predicted the whole-season prevalence for a particular strain until either it or one of the other strains exceeded a specific threshold. An editorial summary of the study states, "These findings suggest that early circulation of one influenza strain is associated with a reduced total incidence of other strains, possibly because of cross-subtype immunity." It also said the algorithm needs to be tested over more flu seasons.
Jul 5 PLoS Med study

FDA clears first antiviral surgical mask
The US Food and Drug Administration (FDA) has granted market clearance to BioMask, the first treated surgical face mask claimed to inactivate virtually all influenza strains in 5 minutes, according to Medscape News yesterday. The BioFriend BioMask (series A), made by Hong Kong–based Filligent, has an inside layer treated with copper and zinc ions, which have been shown in vitro to destroy most influenza viruses. Its outer layer is plastic coated. In a release, the company said, "Market clearance was granted under a new medical device classification for anti-microbial surgical facemasks, 'OUK,' created by the FDA to accommodate Filligent's innovations in infection control and respiratory protection." The company notes on its Web site that "Correlation between in-vitro testing results and any clinical event has not been tested," according to Medscape, and that no clinical study has compared the treated face masks with untreated masks.
Jul 5 Medscape News story
Jun 27 Filligent press release

Connecticut mandates paid sick leave
Connecticut will enact the nation's first law to mandate paid sick leave when a law signed by Gov. Dannel Malloy takes effect Jan 1, according to the Hartford Courant yesterday. The law, signed on Jul 1, applies only to companies with 50 or more workers that don't already offer at least 5 paid days off for full-time workers. It is available to workers after 4 months on the job and exempts manufacturers, salaried workers, temporary workers, and employees of nationally chartered nonprofits. In response to the law, Debra L. Ness, president of the National Partnership for Women & Families (NPWF) said in a news release, "Because of Connecticut's new law, soon hundreds of thousands of workers in the state will no longer have to make impossible choices between their health and their economic security when illness strikes." Studies have shown that not having mandatory paid sick leave was an impediment to ill workers' taking time off during the 2009 H1N1 influenza pandemic.
Jul 5 Hartford Courant story
Jul 5 NPWF news release

Study: Reassortant H9N2-H1N1 viruses transmit well in ferrets
US researchers have found that combining surface genes from H9N2 avian flu with internal genes from 2009 pandemic H1N1 flu produces reassortants that transmit readily to ferrets. In 2009 the researchers showed that an H9N2-H3N2 reassortant virus gained efficient respiratory transmission in ferrets. In the current study they created four reassortant H9N2-pH1N1 genes and found that three showed "efficient respiratory droplet transmission" in the animals. They conclude, "The results clearly indicate that H9N2 avian influenza viruses and pH1N1 viruses, both of which have occasionally infected pigs, have the potential to reassort and generate novel viruses with respiratory transmission potential in mammals."
Jul 5 Proc Natl Acad Sci abstract

Cholera spreads to more Democratic Republic of Congo areas
Health officials in the Democratic Republic of Congo (DRC) announced that a cholera outbreak has spread to three more provinces, which has prompted Doctors Without Borders teams to open several cholera treatment centers, according to a Jul 4 press release from the group. So far the outbreak, which has struck locations along the Congo River, has sickened 2,787 people and killed 153. The outbreak began in March and has spread to several areas, including the outskirts of the country's capital, Kinshasa. The group said three cholera risk factors are all in place in the DRC: a dense urban population, poor sanitation, and little access to clean water.
Jul 4 Doctors Without Borders press release
In other developments, the DRC recently received a $30 million grant from the World Bank to improve polio vaccine coverage and strengthen its capacity to deliver vaccines for other infectious diseases, according to a Jun 28 World Bank press release. The grant is part of $413 million in new financing to help the country build its social protection systems.
Jun 28 World Bank press release

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