The United Nations Food and Agriculture Organization has commended efforts of the Indian government to stop the spread of the deadly avian influenza in the province of West Bengal. The FAO said authorities were able to control the spread of the H5N1 strain with their swift and comprehensive measures.

In a statement, U.N. FAO veterinary expert Mohinder Oberoi said: "Intensive culling in the predominantly backyard poultry sector appears to have stopped the disease in its tracks." He said this after a recent visit to the affected areas, where no new outbreaks have emanated since Feb. 2.

FAO's Chief Veterinary Officer Joseph Domenech, however, urged the country to maintain intensive surveillance in high-risk areas as the possibility of new occurrences remains high.

"The virus could still be present in the environment despite heavy slaughtering and extensive disinfection of affected areas, or it could be reintroduced from other countries," he said.

To achieve rapid control, prevent the spread of the virus to other states and to avoid the risk of human infection, the Indian government had to cull over 3.9 million chickens and ducks, mainly belonging to poor backyard poultry farmers.

"Public awareness campaigns should continue over the next months introducing rural communities to safe poultry production and basic bio-security measures with the ultimate goal of reducing the risk of human infections," the agency added.