Photo Credit, BBC/Ashok Dahal
The Department of Livestock Services has reported that the bird flu virus has spread in 10 districts, including three districts in the Kathmandu Valley, leading to the culling of approximately half a million domestic birds.
Out of the seven provinces, bird flu outbreaks have appeared in four provinces, prompting officials to strongly advise extra caution in poultry farming and trade of poultry products.
Since not all influenza viruses causing bird flu are pathogenic, Nepal officially recognizes only two of the three virus strains under the definition of bird flu.
Currently, the bird flu outbreak in Nepal is attributed to the ‘highly pathogenic’ H5N1 virus strain, known for its high capacity to spread disease.
According to Senior Veterinary Doctor Dr. Navaraj Shrestha of the Department of Livestock Services, Nepal classifies only H5N1 and H7N1 as bird flu viruses. However, the H9N1 virus strain, which has a lower pathogenic capacity and for which vaccines are available in Nepal, is not considered bird flu.
Due to its high pathogenicity, the H5N1 virus requires strict safety and control measures.
“Birds infected with H9N1 rarely die, and the likelihood of human infection is low,” explains Shishir Bhandari, a scientist at the National Agricultural Research Council.
While vaccines against the low pathogenic strain are available in Nepal, vaccines for highly pathogenic strains are accessible in India but not authorized in Nepal.
Officials emphasize that not administering the vaccine remains the primary strategy for controlling bird flu.
What Is the Risk of Transmission to Humans?
Dr. Shrestha, Senior Veterinary Doctor, points out that the first human case of H5N1 infection was reported three decades ago, and the risk of transmission is reduced significantly when chicken meat is thoroughly cooked.
In 2019, Nepal confirmed the death of a young man due to bird flu. Officials reported that he was involved in transporting poultry.
“The mortality rate in humans infected by the virus can be between 48 to 50 percent,” Dr. Shrestha notes.
“Farm workers are at the highest risk. However, if they consistently wear masks, gloves, and boots, and wash their hands and feet after leaving the farm, the risk decreases significantly.”
Where Has the Disease Spread?
According to the Department of Livestock Services, the highest number of bird flu cases have been reported in Sunsari district. Cases have also been confirmed in Morang and Jhapa districts of Koshi Province.
Moreover, bird flu has been documented in Chitwan, located in Bagmati Province, as well as in Kathmandu, Bhaktapur, and Lalitpur districts.
The disease has also emerged in Baraa and Mahottari districts of Madhesh Province and in Nawalparasi West of Lumbini Province.
The Department reports that over 500,000 birds have been culled across more than 72 affected poultry farms in these 10 districts.
In the Kathmandu Valley, most infected birds are local breeds and layers. Vet Dr. Shrestha attributes the spread of the virus to the reuse of egg crates and poor management practices in poultry farming.
Is the Bird Flu Outbreak Linked to Indian Elections?
Photo Credit, BBC/Ashok Dahal
Before bird flu was detected near Kakarvitta in Nepal in 2009, it had been reported in India. Similarly, after cases appeared in Patna, India, the outbreak started soon after in Morang district.
Nepalese officials suspect that increased imports of poultry and eggs from India prior to the Feb 21 elections may have introduced the virus, though this has not been officially confirmed.
Scientist Bhandari, who studies avian diseases, says the likelihood of bird flu entering Nepal through formal imports from India is low.
“Bird flu can spread through both migratory birds and domestic poultry,” Bhandari explains.
“If bird flu is absent in Nepal, infections could be brought in by wild birds and poultry products from outside. Formal imports undergo quarantine, so risk is low. However, due to the open border with India, informal movement of birds is possible.”
Why Has This Outbreak Occurred Now?
The current weather conditions are highly conducive to the spread of infectious diseases, making it easier for infections to transmit, explains researcher Bhandari.
“Viruses and bacteria spread more efficiently in conditions with suitable temperature and humidity, and biosecurity measures are weakened during this period,” he adds.
Studies show that the bird flu virus thrives best between 4 and 10 degrees Celsius. However, health officials are surprised to find the virus surviving even in the current warmer season.
“The presence of the virus until Ashad (mid-June) suggests it may have developed tolerance to heat. This has yet to be formally studied, but we have observed such trends,” he notes.
Is This a Full-Scale Bird Flu Outbreak?
Bird flu has been detected during the months of Falgun and Chaitra (February–March) continuously for two years in Nepal. Data shows outbreaks primarily in Indian border districts of Koshi Province.
On Falgun 5, 2081 BS (mid-February 2025), bird flu was reported in Sunsari, and again on Chaitra 4, 2082 BS (mid-March 2026) in two localities of Morang.
The current outbreak, starting from Chaitra (mid-March), has not been fully contained even by the last week of Jestha (mid-June). Researchers state the virus level is not yet at outbreak scale.
The Department of Livestock Services also classifies the spread as concerning but not an outbreak.
“Most cases are currently concentrated in the three districts of the Kathmandu Valley,” says vet Dr. Shrestha.
How to Take Precautions?
The primary reasons for the spread of bird flu in Nepal include violations of quarantine rules, weak biosecurity, and poor sanitation in places where poultry such as chickens and ducks are kept.
Besides several large farms, most small farms have experienced higher infection rates.
“A single vehicle transports chickens, chicks, eggs and feed. This same vehicle then visits multiple farms and reuses empty crates for eggs, which greatly promotes the spread,” says Bhandari.
Veterinarian Dr. Shrestha, who has monitored many affected farms, notes, “Poultry is often reared in unsuitable locations lacking adequate biosecurity, fencing, and control measures.”
He advises enhanced caution in poultry farming and recommends constructing poultry enclosures at a safe distance from residential areas.
“Crows have also been found to spread this infection. Infected farms often have crows and their fatalities could be a source,” he adds.
