A 56-year-old woman in China has died from H3N8 bird flu, making her the first known human fatality caused by this subtype of avian influenza. According to experts, the victim is believed to have contracted the virus after visiting a wet market where live birds were being sold. This marks the third known case of H3N8 infection in humans, with two unrelated cases in China, reported last year, both of which resulted in recovery. The woman who died had underlying health conditions and developed symptoms in late February before passing away on March 16th. Scientists have collected positive samples of H3N8 from the wet market where the victim was believed to have contracted the virus.
While H3N8 is one of the more commonly found subtypes of avian flu in birds, it is less dangerous than the H5N1 bird flu pandemic that has devastated bird populations worldwide and has spread to mammals such as foxes, sea lions, and even domestic cats. However, H3N8 has also been detected in various mammals before, including horses and dogs. An outbreak of H3N8 among harbour seals in New England, US, in 2011 killed 162 animals.
There is currently no evidence to suggest that H3N8 can be transmitted from person to person. The World Health Organization confirmed that none of the victim’s close contacts developed any infection or symptoms of illness at the time of reporting.
There are numerous types of avian influenza, with the viruses being described by two different proteins, hemagglutinin and neuraminidase (the H and N in the naming sequence). To date, scientists have identified 18 different subtypes of the former and 11 of the latter in circulation. Of these, only six have infected humans, with H5N1 and H7N9 accounting for most known cases.
Although H3N8 viruses have been sporadically detected in poultry in China, there remains a greater concern about the H5N1 bird flu pandemic. The number of cases in birds and the increasing transmission in mammals, including mink, otters, and even pet cats, raise the risk of the virus mutating and becoming capable of spreading between humans. According to Dr Pablo Plaza, an expert in veterinary public health and epidemiology, the risk seems low at present, but vigilance is essential as the virus is continually changing. Several changes in the virus are required to adapt to human-human transmission, which hopefully will not occur.
