NEWS SCAN: Severe-flu gene?, H1N1 deaths in India, flu vaccine patent, foodborne norovirus outbreaks

Mar 26, 2012

Researchers pinpoint gene that may play role in severe flu cases
A genetic finding may help explain why the same influenza strain produces serious, even life-threatening symptoms in some people but only mild manifestations in others, according to a study yesterday in Nature. UK and US researchers found that people who carry a specific variant of a gene called IFITM3 are significantly more likely to be hospitalized when infected with influenza than those who carry other variants. The IFITM3 gene has been shown in genetic-screening studies to block the growth of flu and dengue viruses in cells, according to a Wellcome Trust news release on the study. This finding led the team to test the gene's role in viral protection in mice. They found that removing the gene from mice turned mild flu cases fatal. The researchers then sequenced the IFITM3 genes of 53 patients hospitalized with flu and found that a statistically significant number had an IFITM3 variant (SNP rs12252-C) that is rare in the general population. "Collectively, these data reveal that the action of a single antiviral protein, IFITM3, can profoundly alter the course of the flu and potentially other viruses in both human and mouse," said co–senior author Paul Kellam, PhD, from the Wellcome Trust Sanger Institute, in the release. Abraham Brass,  MD, Phd, of the Massachusetts General Hospital, the other co–senior author, added, "Our efforts suggest that individuals and populations with less IFITM3 activity may be at increased risk during a pandemic."
Mar 25 Nature abstract
Mar 25 Wellcome Trust news release

India reports 12 recent H1N1 deaths
A rise in pandemic 2009 H1N1 (pH1N1) flu infections in India has led to 12 deaths this month, according to BBC News. Half of those deaths were in the western state of Maharashtra, with Rajasthan, Andhra Pradesh, and Karnatak also reporting pH1N1 deaths, according to Health Secretary P. K. Pradhan. Nearly 130 people have become infected in the country, with many of them hospitalized. In Pune, Maharashtra's second-largest city after Mumbai, hospitals are seeing new pH1N1 patients every day, according to a local journalist.
Mar 23 BBC News report

Patent granted for H1N1 component of Inovio's 'universal' flu vaccine
Inovio Pharmaceuticals Inc. announced today that a US patient has been granted for its vaccine designed to target multiple strains of H1N1 influenza. The firm's SynCon H1 antigen is part of its INO-3510 vaccine, which targets the H1N1 and H5N1 subtypes. "The patent includes claims that cover the synthetic consensus H1 antigen and DNA constructs and vaccines that include this antigen, including universal influenza vaccine INO-3510," which is in phase 1 clinical testing, the company said in a press release. It said its H1N1 and H5N1 constructs are based on a genetic consensus of multiple strains in an attempt to confer broad protection. In separate animal studies, the H1N1 vaccine provided 100% protection against pH1N1 and the 1918 pandemic H1N1 virus, and in other animal studies the vaccine generated protective levels of antibodies against other H1N1 strains, the firm said. The statement said the patent was granted to the University of Pennsylvania and has been licensed to Inovio under an existing agreement.
Mar 26 Inovio press release

Study suggests foodborne norovirus outbreaks are worst kind
A systematic review of the literature suggests that norovirus outbreaks spread by food or water and those that occur in winter are linked to higher attack rates than outbreaks that spread by other means and occur in other seasons, according to a report today in Epidemiology and Infection. Researchers from Emory University and the University of Michigan analyzed reports of 902 confirmed norovirus outbreaks that occurred between 1993 and 2011, looking for associations between transmission route, setting, attack rates, and the occurrence of genogroup I or II. Regression analyses showed that attack rates were significantly higher in outbreaks related to food and water, as compared with "person-to-person and environmental outbreaks," the researchers report. They also found that outbreaks in healthcare settings involved "low primary attack rates," probably because of effective infection control practices. "Point-source outbreaks (eg, food) were associated with the highest illness burden, primary attack rates, and proportion of outbreaks and were more likely to be caused by strains from multiple genogroups," the authors state. The latter point, they add, suggests that several primer sets should be used to detect norovirus from point-source outbreak specimens.
Mar 26 Epidemiol Infect abstract

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