KATHMANDU, JUNE 30 Bird flu continues to spread in and around the Kathmandu Valley, with more than 40,000 ducks and layer chickens culled in Kavrepalanchok as authorities intensify containment efforts against the highly contagious disease. According to the District Livestock Service Office, Dhulikhel, a total of 40,729 ducks and layer chickens have been destroyed after avian influenza was confirmed at commercial poultry farms in Banepa Municipality wards 6 and 13 and Panauti Municipality wards 7, 8 and 9. Senior Veterinary Officer Dr Bajra Kishor Thakur said the improper disposal of dead poultry in rivers, bushes and other open areas has likely contributed to the spread of the virus through crows and other wild birds. The latest culling comes as the Department of Livestock Services has warned that infected crows have become a major driver of bird flu transmission across the Kathmandu Valley, making the outbreak harder to contain than infections limited to poultry farms. Director General Dr Umesh Dahal said infected crows can carry and spread the virus for up to 21 days, transmitting it over long distances through movement and droppings. He said bird flu has now been detected across all three Valley districts, with containment efforts still underway in Kirtipur and Kageshwori Manohara, while the situation has largely been brought under control elsewhere. Authorities have stepped up surveillance at Nala, Roshi and Khawa checkpoints in Kavre to prevent the illegal transport of poultry without health certification. Poultry farmers have also been urged to strictly enforce biosecurity measures, including restricting unnecessary access to poultry sheds, maintaining regular disinfection and ensuring safe transportation practices. The outbreak, first reported in Morang in March, has now spread to 11 districts and nearly 100 poultry farms nationwide. According to the Department of Livestock Services, about 570,000 birds have been affected so far, while nearly one million eggs and more than 195,000 kilograms of poultry feed have been destroyed as part of disease-control measures. The outbreak has also disrupted public facilities. The Central Zoo in Jawalakhel remains closed after bird flu was detected in crows, pigeons and several other animal species, including civet cats and clouded leopards. Officials have warned that delays in laboratory test results have hampered timely response in some areas, allowing infections to spread further. They have urged poultry farmers and the public to remain vigilant, noting that although bird flu primarily affects birds, certain strains also have the potential to infect humans.