Nepal, June 28 -- Crows have been identified as a major factor behind the spread of bird flu across the Kathmandu Valley, according to the Department of Livestock Services.

Director General Dr Umesh Dahal said the virus has spread widely after being detected in crows, which can carry the infection from one location to another. While outbreaks in poultry can be contained, controlling the disease in wild crows is not feasible, he said, adding that crows have transmitted the virus to several areas, including the Central Zoo.

According to Dr Dahal, infected crows can remain contagious for up to 21 days. Dead crows and their droppings can also contribute to the spread of the virus.

Bird flu cases have now been reported in all three distric...