The H7N9 bird flu virus has not been detected in the nation's poultry farms, with positive samples mainly coming from live poultry markets, China's Ministry of Agriculture (MOA) said Thursday.

The MOA said it has "basically" finished collecting and testing 899,758 samples from across most parts of the country.

Of the total tested, 53 samples were found positive for H7N9. Fifty-one positive samples came from 18 live poultry markets in Shanghai and from Anhui, Zhejiang, Jiangsu, Henan, Shandong, Guangdong, Jiangxi and Fujian provinces, the MOA said in a statement.

The other two positive samples came from wild pigeons in Nanjing, capital of Jiangsu Province and domestic pigeons in Nantong, in Jiangsu Province.

Experts believe live poultry markets pose more danger and farms should step up efforts to guard against the virus, the statement said.

The H7N9 virus has not been found to be lethal to chicken and ducks, according to research from the national bird flu reference laboratory.

Also, no pigs were found to have caught the virus, the MOA said.

The virus has killed 36 people on the Chinese mainland, said the National Health and Family Planning Commission on Monday.