FAO rules out human-to-animal transmission of influenza A(H7N9)

Uncontrolled live poultry trade poses the highest risk of A(H7N9) introduction.

19 February 2014, Rome – FAO says there is no evidence that human patients infected with influenza A(H7N9), a low pathogenic virus in poultry, can transmit the virus to animals, including birds.

FAO referred to the first human case of A(H7N9) outside China, which was recently detected in Malaysia.

The patient, originally from Guangdong Province in China, where she is thought to have contracted the infection, was visiting Malaysia as a tourist and has now been hospitalized there. Guangdong is one of the Chinese provinces most affected by the A(H7N9) virus in 2014.

“This case does not come as a surprise and should not be a cause for increased concern, but should remind the world to remain vigilant," said FAO Chief Veterinary Officer Juan Lubroth.

“Humans that become ill with influenza A(H7N9) constitute no threat to poultry populations,” Lubroth underlined.

“In fact, we have no evidence that affected people could transmit the virus to other species, including birds. The highest risk of virus introduction is uncontrolled live poultry trade between affected and unaffected areas.”

People, on the other hand, become infected following close contact with infected live poultry, mostly in live bird markets or when slaughtering birds at home.

WHO risk assessments show that should infected people from affected areas travel internationally, community level spread is unlikely since the virus does not have the ability to transmit easily among humans.

Lubroth observed that "Such 'imported’ human cases, like the one reported in Malaysia last week, have been found in the past in previously unaffected areas of China, like Guizhou, Taiwan Province of China and Hong Kong SAR, and we will likely continue to see this in the not too distant future again. To date the virus has not been found in poultry populations outside affected areas in China."

Birds that have contracted A(H7N9) do not show clinical signs, which renders early detection of the virus in poultry populations more difficult. FAO therefore urges countries to adapt their surveillance programmes to include this recently emerged virus.

One of the main recommendations is to target surveillance at critical points of entry, where direct or indirect live poultry trade with infected areas might occur.

In order to reduce human exposure to zoonotic pathogens in general, biosecurity measures should be introduced or reinforced at live bird markets, including frequent cleaning and disinfection, establishing market rest days with no poultry present and applying good hygiene standards.

With the strong support of the United States Agency for International Development (USAID),  FAO is assisting a number of member countries to prepare for a potential introduction of A(H7N9) into their poultry populations.

FAO is focusing in particular on high risk countries, facilitating: (i) risk assessment; (ii) contingency planning; (iii) expansion of diagnostic capabilities; and (iv) risk-based surveillance.