News Update

As of April 29, 2013, the World Health Organization reports a total of 126 confirmed cases of Avian Influenza A: H7N9 human infections from multiple areas in China. Of the 126 confirmed cases, 24 have resulted in death. Taiwanese authorities also report 1 human case in a Taiwanese citizen who traveled to China. The majority of H7N9 cases seem to be caused by exposure to infected birds, primarily chickens and ducks. So far there is no evidence to suggest H7N9 has sustained human-to-human transmission; however, at least three family clusters of two or three confirmed cases may have been from limited human-to-human transmission.

As of April 30, 2013, Chinese investigators had posted 19 genome sequences from H7N9 viruses. Genetic changes found in the sequences are associated with viral adaptations that allow for enhanced binding to and replication within mammalian respiratory cells and with increased infection severity.

Meanwhile, the CDC, along with state and local health departments, is continuing surveillance for influenza in the United States and has initiated enhanced surveillance for H7N9 among patients who had returned from China recently. As of April 29, 37 travelers had been reported to the CDC by 18 states. None of the travelers had H7N9 infection.

Since there is no vaccine currently available for Avian Influenza A: H7N9, the CDC has also updated its infection control guidelines. The CDC recommends that all H7N9 patients (confirmed or suspected) receive antiviral treatment with oral oseltamivir or inhaled zanamivir as early as possible. Travelers to China are also encouraged to practice good hygiene and follow food safety practices while traveling in China. Should travelers become ill with influenza signs or symptoms, they are encouraged to seek medical treatment.

CDC Morbidity and Mortality Weekly Report

Image Source: CDC