Over the past two weeks a new type of bird flu, dubbed H7N9, emerged in China and began to spread. On March 31, authorities reported that two men, an 87- and a 27-year-old, died in Shanghai and that a third in a nearby town was seriously ill. On April 2, the total number of cases grew to seven. On April 7, the World Health Organization recorded 21 cases with six deaths. Now, says Bloomberg, the total number of confirmed cases has grown to sixty, with 13 deaths. Originally centralized in and around Shanghai, the BBC reports that the novel influenza strain has spread to Beijing, some 775 miles to the northwest.
Antiviral medication delivered early can help temper the damage, but “almost all of the 64 people diagnosed with the virus so far have been extremely unwell, with complications extending to brain damage, multi-organ failure and muscle breakdown,” says Bloomberg.
That’s still a relatively low number of cases, within a generally confined geographic spread. But there are a few key factors to H7N9 that make it worth paying attention to as a potentially very dangerous new strain of flu.
First, according to the Associated Press, though the influenza started in and is carried by birds, such as chickens and ducks, it doesn’t seem to actually make the birds very sick.
The scientists said that based on information from the genetic data and Chinese lab testing, the H7N9 virus appears to infect some birds without causing any noticeable symptoms. Without obvious outbreaks of dying chickens or birds to focus efforts on, authorities could face a challenge in trying to trace the source of the infection and stop the spread.
According to Helen Branswell for the Canadian Press, the bird flu is showing signs that it has adapted to better live in mammals. That being said, “health officials believe people are contracting the H7N9 virus through direct contact with infected fowl and say there is no evidence the virus is spreading easily among people,” says the AP.
Then, says Reuters, scientists think that H7N9, which only recently adapted to be able to infect humans, is still changing, “swapping genes with other strains, seeking to select ones that might make it fitter.”
“If it succeeds, the world could be facing the threat of a deadly flu pandemic. But it may also fail and just fizzle out.”
A more wide-ranging investigation, where health workers checked the neighbors and close contacts of those who showed up in the hospital with symptoms, found that some people are carrying the virus but aren’t—or aren’t yet—showing symptoms, says Bloomberg. Such “asymptomatic” cases mean that more people may have the disease than have been reported, increasing the potential for H7N9 to turn into a much bigger problem.
There is no guarantee that H7N9 will take off and become a wide-spread pandemic, but health authorities, including the U.S. and Chinese Centers for Disease Control and the World Health Organization, are watching very carefully. Health reporter Maryn McKenna has a number of tips on how to read the news and who to look to for the latest information.
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