A new strain of avian influenza, which has high pathogenicity in poultry and can be deadly for humans has surfaced in China, raising fears of a potential pandemic, the UN Food and Agriculture Organization (FAO) reported.
The FAO said the new strain represented a worrisome mutation of the H7N9 virus, because until now, it has shown low pathogenicity, meaning that it causes only mild or no illness in poultry. Data from China’s Guangdong province suggests, however, that the new strain has shifted to high pathogenicity in poultry while retaining its capacity to cause severe illness in humans.
Reports indicated that the new strain of H7N9 could lead to high mortality for birds within 48 hours of infection, which could subsequently cause serious economic losses for the poultry industry.
The FAO said that human cases of bird flu have been increasing in China, but did not link these with the new strain of the H7N9 virus. In its March update, the FAO said that 20 human cases were reported in Hunan, Jiangsu, Guangxi, Fujian, Guizhou, Chongqing, Shandong and Zhejiang provinces, and in its April 12 update, the FAO reported 16 more cases, as well as two detected in birds.
So far, there is no indication that the new strain of the virus has spread to wild birds, the FAO said, and it has not been detected in poultry in other countries.
“However, these countries (with poultry farms) remain at risk and need to be vigilant for a potential incursion of the virus, in a low or highly pathogenic form,” Matthew Stone, Deputy Director General of the World Organization for Animal Health said in a statement. “Constant surveillance of domestic poultry as well as wild birds by national veterinary services is essential to reduce the risks associated with virus spread and protect both animal and human health, as well as livelihoods.”
“China has embarked on intensified surveillance and results are awaited to better assess the epidemiology and potential spread of this new, highly pathogenic virus,” Sophie Von Dobschuetz, Animal Health Officer at FAO, said. “FAO, through its office in Beijing, is in regular dialogue with the ministry of agriculture and providing recommendations for surveillance and control.”
As in previous human cases of the infection, most of the recently reported human cases of bird flu in China were the result of visiting live bird markets or coming into contact with infected birds on farms. Stone said that prevention measures to curb the spread of the H7N9 virus should include laboratory testing, increased hygiene at live bird markets and on-farm biosecurity to reduce exposure.