May 8, 2013 (CIDRAP News) – Another patient in China has died from an H7N9 influenza infection, raising the number of fatal illnesses to 32, though no new cases were reported today, holding the overall case total to 131.
The World Health Organization (WHO) reported the death today in an update based on information from China's National Health and Family Planning Commission.
The report did not contain any details about the patient who died or his or her location, though the WHO said on its Twitter feed that the death was a retrospective one.
The WHO's update on H7N9 cases today also acknowledged the infection of a 79-year-old woman from Jianxi province whose case was first announced by Chinese officials yesterday. The WHO said she started having symptoms on May 3. Yesterday Hong Kong's Centre for Health Protection (CHP) said the woman is in stable condition.
In addition, the European Centre for Disease Prevention and Control (ECDC) today published the second update of its rapid risk assessment on H7N9 influenza but said the overall risk to Europe from the disease hasn't changed. So far nearly all of the cases are sporadic, it said, with no obvious epidemiologic links.
"While occasional human-to-human transmission in the clusters cannot be ruled out, there is certainly no confirmation of sustained human-to-human transmission," the ECDC said.
Influenza experts say the slowed pace of new H7N9 cases over the past several days doesn't suggest that control efforts have removed the threat, and it's not clear if the virus will fade out or continue to circulate at lower levels during warmer months, a pattern sometimes seen with other flu viruses, The Canadian Press reported today.
Michael Osterholm, PhD, MPH, director of the University of Minnesota's Center for Infectious Disease Research and Policy, publisher of CIDRAP News, said that 2 weeks of activity doesn't amount to a trend and that it's impossible to predict if flu activity will wane when the weather warms. He pointed to active transmission of variant H3N2 viruses in connection with US state and country fairs and an August rise in activity during the 2009 H1N1 pandemic.
Other flu experts worried that the downturn in cases lead to people lowering their guard about the disease. Keiji Fukuda, MD, the WHO's assistant director-general for health security and environment, told the Canadian Press that flu fatigue may make it harder to get the prevention message across, but the WHO and its global partners will press ahead with situational awareness activities.
In other developments, Medicago, a pharmaceutical company based in Quebec, announced today that it has produced a virus-like-particle (VLP) vaccine candidate against the H7N9 virus, according to a company statement.
Medicago obtained the hemagglutinin (HA) sequence for the H7 vaccine from the GISAID database. (Its vaccine does not require the isolate.) It thanked Dr Jun Li and the Hangzhou Center for Disease Control for sharing the sequence of the isolate obtained from a patient in Zhejiang province.
The company is purifying the vaccine to prepare for immunogenicity studies in animals, according to the statement. VLP vaccines mimic the structure of a virus but don't contain any viral DNA or RNA. They can be produced in a variety of platforms; Medicago's is plant based.
Andy Sheldon, Medicago's president and chief executive officer, said in the statement that the platform is poised to dramatically speed the development of an H7 vaccine, compared with traditional egg-based methods that can take up to 6 months. Vaccine production facilities in Canada and North Carolina position the company as a key player in addressing a potential pandemic, he said.
An October report from the CIDRAP Comprehensive Influenza Vaccine Initiative (CCIVI) said VLP vaccines are among the new technologies under development that could make more flu vaccine faster, but it's not clear yet if the new vaccines would be more effective than currently available ones.
The US Centers for Disease Control and Prevention and its partners are working on an H7N9 candidate vaccine virus and are making plans for vaccine trials, but no decisions have been made to launch an H7N9 vaccine program. The WHO on May 2 said its collaborating centers and other network labs are currently developing high-growth reassortants that could be used in vaccine development, if a vaccine is needed.
May 8 WHO update
WHO Twitter feed
May 8 CHP statement
May 8 ECDC statement
May 8 Canadian Press report
May 8 Medicago press release
Oct 15, 2012, CCIVI report