GlobalHealth Threats

The World Health Organization (WHO) conducted a media briefing (audiofile) to provide updates on avian flus including slight increase in antiviral resistance among H7N9 viruses. Health officials from the WHO's global influenza program, Chinese Center for Disease Control and Prevention and US Centers for Disease Control and Prevention addressed concerns around avian influenza, particularly those related to H7N9.  

The fifth wave of human H7N9 infections in China saw more than one third of the total cases since 2013. But epidemiological characteristics of the virus remain similar as before. Notably, about seven percent of the H7N9 viruses had genetic features of antivirals resistance. These strains were obtained from human cases but not from poultry. Hence, the feature possibly developed following administration of antivirals during treatment. The core message from the experts was that the risk of sustained human to human transmission of H7N9 remains low. Sporadic human infections will continue to occur as long as the virus circulates in poultry. 

The discussion also included the change of pathogenicity of H7N9 from low to high. This is applicable to birds only and there is no evidence in change of pathogenicity for human infections. There are no new clinical recommendations and the experts emphasised on preventive measures to protect from the disease. 

The health officials also spoke on the spread of H5N8 viruses in recent times in Europe, Middle East and Africa. They acknowledged that H5 viruses are capable of changing genetic makeup. WHO in collaboration with China and US CDC’s are sharing genetic information and closely monitoring the situation.