As of April 25th, China's National Health and Family Planning Commission had confirmed a total of 109 cases of H7N9 avian flu. 23 of these cases (or roughly 21 percent) have been fatal and there are now signs the virus has infected people living outside mainland China.
While both the spread and the virulence of H7N9 are solidly documented, the exact method of transmission is still somewhat of a mystery. During past outbreaks of avian flu, the virus was being spread from poultry to people – that's why mass culls of chicken and duck farms could effectively nip potential flu epidemics in the bud.
Influenza (of all types) becomes a real danger, however, when the virus mutates to a form easily transmitted between humans without any animal vector. Lately there are signs this may be happening, and one vector facilitating human-to-human spread of the virus is as unexpected as it is common: poultry feather removal machines.
Poultry feather removal machines are commonly used to pluck freshly slaughtered chickens, ducks and geese at China's urban live poultry markets.
To prepare birds for customers, market sellers spin them in machines into which hot water is added. The tubs then spin at high speeds, quickly and efficiently plucking the feathers. Trouble is, droplets of steam and spray emanating from the machines could carry H7N9 bird flu viruses directly into the lungs of sellers, customers, and anyone else in the area.
“If there is a virus, it can be easily inhaled this way,” explained Feng Zijian, director of the emergency response center of the Chinese Center for Disease Control and Prevention, in a recent briefing with Chinese reporters.
“This is what we suspect to be a major environmental exposure that causes human infections.” Once inhaled into the lungs of one human, a simple cough, sneeze or sigh could release the virus into society time and time again, far from the nearest infected chicken.
Large poultry feather removal machines are mainly employed by commercial poultry producers in Western countries, whereas in China much smaller machines are a common feature at the live poultry markets where the majority of Chinese consumers buy their poultry. Should these machines be positively identified as an influenza transmission vector, the resulting disruption to China's food distribution system would be massive to say the least. (via M.I.C Gadget, USA Today, Apple Daily HK, and OLX)