Iran has culled 1.4 million chickens in a province east of the country to contain the spread of the severe bird flu, known as H5N8.
Head of Iran Veterinary Organization said on Saturday that a bulk of the birds slaughtered over H5N8 fears had been concentrated in industrial poultry units in South Khorasan province.
Ali Asqar Makanali said that virus spread fast in an area of 15 kilometers around a single poultry farm because owners had decided to hide the infection from authorities.
Culls of 1.4 million chickens are relatively rare in Iran, a country with a poultry flock of 75 million in 1,701 farms.
Iranian authorities have had strict controls in place in the past few years to contain small-scale bird flu outbreaks that have occurred sporadically in the country.
Makanali said there would be no further culls and preventive slaughtering in Iran because the spread of the virus appeared to be under control.
He said, however, that the virus had four different strains in Iran and authorities were using advance molecular diagnostics systems to detect any small-scale outbreak.
The official said that the World health Organization (WHO) had been informed through a series of “transparent reports” about the detection and control of the bird flu outbreaks in 50 locations in Iran.