Chicken (via Flickr/Tomasz Nowicki)
On Mar. 17, 2016, an 81-year-old woman in Hong Kong was admitted to the hospital for pneumonia and later transferred after testing positive for the H7N9 strain of avian influenza. She is currently stable. She visited a wet market while visiting Kaiping, Guangdong Province, and was exposed to recently slaughtered poultry.
Three other people, a 45-year-old man from Xuancheng and a 43-year-old mother and her 23-year-old son from Ji’an City, contracted H7N9 recently. The man is in critical condition, while the mother and son are stable.
Another case was reported in the Hubei Province with the H5N6 strain. A 35-year-old man checked into the hospital on April 12 and is in critical condition.
Other than the 81-year-old woman, it is unknown how these people were exposed. However, wet markets, where live or recently slaughtered poultry are sold, are prime suspects, particularly in cities where inhabitants are rarely in contact with farm animals.
The difficulty of controlling exposure in wet markets is well known. In February 2015, positive tests for H7N9 caused Guangzhou to ban live poultry from wet markets for five days. The ban was ineffective, as sellers illegally sold birds outside the market or in private homes and apartments.
Buyers cooperate, as they want freshly slaughtered animals and often disbelieve the warnings that have been issued by the government. The Chinese government needs to increase awareness of the dangers of avian influenza for the poorest segments of the population, who may have limited internet access and poor reading skills.
Mother and son cases
Fresh and Live Chickens Sold at a Market in Laos (Photo via Flickr/Shankar s).
In Suzhou City, China, a 60-year-old man contracted the first known case of the H7N9 avian influenza strain of the year. He was diagnosed with pneumonia by several hospitals, but eventually testing by Hong Kong’s Public Health Laboratory Services revealed that he had H7N9. He was moved to Princess Margaret Hospital on Feb. 23, and his wife, son and others close to him are being monitored.
The man reported that he had no contact with live poultry, but it is known that he visited a wet market. These common, traditionally outdoor markets serve the poor in China, and they usually sell fresh meat, produce and live animals. However, some newer indoor wet markets may lack live animals.
It is unconfirmed whether the man visited a market with live poultry or not. Although he said that he had no contact with poultry, he may consider contact to be physical interaction with live birds and not realize there are alternate methods of contagion.
The most common way that avian influenza can pass to people is through accidental contact with bird feces. In addition, it is believed that inhaling aerosolized material in wet markets is one of the main ways that humans can get infected. Thus, this man could have been infected by the former or the latter.
Unfortunately, despite yet another case of avian influenza being attributed to wet markets, the practice of selling live poultry is likely to continue in China. Hong Kong’s government proposed central slaughterhouses for chickens in 2008 but was met with public backlash, as customers want to be able to inspect the birds which they buy. However, because of the number of cases of avian influenza contracted last year in China, it is possible that the government will institute new policies despite protests.
First Case of H7N9