A medical worker at a Shanghai hospital died from bird flu, stoking concern that the influenza virus known as H7N9 may have spread from person to person.
The 31-year-old man died on Jan. 18, according to a statement on the Shanghai Municipal Commission of Health and Family Planning website today. The city has identified seven cases of infection with the virus this year, the statement said.
Human cases of H7N9 were first reported in China in March and spiked in April before agriculture authorities temporarily closed live poultry markets to limit human exposure. The World Health Organization has reported 199 laboratory-confirmed cases and 52 deaths since the start of the outbreak.
“It’s always a concern when health workers die,” said Gregory Hartl, a spokesman for the WHO in Geneva. “Hospitals and other medical facilities are a flash point for human-to-human transmission. We would be very much wanting to follow up in as much detail as possible on this case.”
Even though H7N9 hasn’t mutated to become as contagious as seasonal flu, strains that emerge in China are of interest to researchers. The 1957-58 Asian Flu and 1968-69 Hong Kong Flu pandemics were first identified in the world’s most populous nation. Another bird-flu strain known as H5N1 is thought to have come from the southern province of Guangdong in 1996.
“We need more evidence before increasing our level of concern,” Ben Cowling, an associate professor of infectious disease epidemiology at the University of Hong Kong’s school of public health, said on the Shanghai medical worker’s death. “We know that there’s always potential risk for health-care workers treating cases of H7N9 to be infected.”
Human infections may rise further during Chinese New Year celebrations, when millions of people are expected to travel and households will slaughter poultry for festive meals, the Food and Agriculture Organization of the United Nations said in a statement today. China’s New Year holiday begins Jan. 31.
Laboratory experiments using ferrets -- the most common animal model for human flu infections -- have shown that the H7N9 virus is capable of spreading from person to person. Some small family clusters have been reported, though in December the WHO said it hadn’t seen any evidence of sustainable human-to-human transmission.
H7N9 has turned up outside mainland China, in locations such as Hong Kong. It can circulate widely in chickens, ducks and geese without causing the mass die-offs characteristic of the more infamous bird flu virus H5N1. The germ is typically more active during the colder winter months, scientists have said.