The most recent outbreak of H7N9 influenza in China has infected 460 people since October, making it the largest epidemic of avian flu since 2013, according to the CDC's Morbidity and Mortality Weekly Report.
While the CDC is working to develop a vaccine for avian influenza, analysis of viral samples from the most recent outbreak revealed the H7N9 strain is mutating, forcing the agency to start work on a second vaccine, according to NBC News.
"The surge in numbers of human H7N9 cases in China is definitely a concern," Tim Uyeki, MD, a flu expert with the CDC, told NBC News.
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Early symptoms of H7N9 are comparable to that of seasonal flu. However, the virus often progresses to pneumonia. The avian flu strain is one of several monitored by the CDC and other health agencies because of its potential to cause a human pandemic.
"Although the current risk to the public's health from [H7N9] viruses is low, among the 12 novel influenza A viruses evaluated...[H7N9] viruses have the highest risk score and are characterized as posing moderate [to] high potential pandemic risk," wrote the authors of the CDC report.
To learn more about H7N9 and the CDC's travel guidance for China, click here.
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