New Delhi, 30 August 2025: The National Zoological Park in New Delhi, popularly known as the Delhi Zoo, has been temporarily shut down after two painted storks tested positive for the highly contagious H5N1 bird flu virus. The move, announced on Saturday, August 30, 2025, is a precautionary measure aimed at protecting public health, safeguarding the zoo’s animals, and containing the spread of the infection.
The closure has sparked concern among visitors, conservationists, and health authorities, given that bird flu outbreaks not only threaten avian populations but can also have broader implications for human and animal health.
Sudden Deaths Raise Alarm
The first sign of trouble emerged earlier this week when two painted storks housed in the zoo’s water bird aviary died suddenly. Their samples were immediately sent for testing, and the results confirmed that both birds were infected with the H5N1 strain of avian influenza.
H5N1 is a highly pathogenic virus known for its rapid spread among birds and occasional transmission to mammals, including humans. Once the results arrived, authorities wasted no time in implementing a complete lockdown of the zoo to visitors, ensuring that the situation could be contained before escalating further.
Immediate Closure and Emergency Measures
Following the confirmation of the infection, the zoo was closed indefinitely starting August 30. Entry for visitors, educational tours, and other public activities was halted with immediate effect. Zoo authorities, along with national animal health agencies, began deploying biosecurity protocols to curb the spread.
Some of the measures already in place include:
- Enhanced surveillance across all bird enclosures.
- Isolation and observation of waterfowl and migratory birds.
- Stringent disinfection drives within and around the aviaries.
- Restrictions on staff movement, ensuring that caretakers follow safety guidelines such as protective clothing, sanitization, and limited contact with animals.
Officials also activated the National Action Plan for Avian Influenza, which lays out a step-by-step protocol to handle such outbreaks, from containment to environmental sampling and eventual clearance for reopening.
Past Bird Flu Incidents at Delhi Zoo
This is not the first time the Delhi Zoo has faced the challenge of avian influenza. Similar outbreaks were reported in 2016 and 2021, forcing temporary closures. Each time, the virus was detected among migratory or captive birds, and the zoo had to implement strict biosecurity measures to resume operations.
Experts point out that the zoo’s geographical location makes it a potential hotspot for avian flu, especially during migratory seasons when birds from across regions flock to Delhi. These migratory birds can act as carriers, introducing the virus into local avian populations.
Why the H5N1 Virus Is Concerning
H5N1 avian influenza is regarded as one of the most dangerous strains of bird flu. It spreads rapidly among birds, causing high mortality rates. Infected birds often show symptoms such as ruffled feathers, loss of appetite, respiratory distress, and sudden death, though in some cases the virus can spread silently.
The virus has also been known to cross species barriers. While rare, human infections with H5N1 have been documented globally, with severe illness and high fatality rates. This zoonotic potential makes outbreaks a matter of public health concern, not just an issue of animal welfare.
Impact on Zoo Operations and Visitors
The sudden closure of the zoo has left many visitors disappointed, especially those who had planned outings during the ongoing holiday season. The National Zoological Park is one of Delhi’s most popular attractions, drawing thousands of visitors every week.
Beyond tourism, the closure also impacts conservation and research activities. Educational programs, student visits, and guided tours have all been suspended. The focus has shifted entirely to disease containment and animal monitoring.
Zoo staff, including veterinarians and caretakers, have been placed on high alert. Special monitoring teams are observing not just the birds but also mammals such as tigers and lions, as previous global cases have shown bird flu infections in big cats fed on infected poultry.
Containment Protocols and Testing Timeline
Authorities have made it clear that the next three weeks will be critical in determining the zoo’s reopening. Continuous surveillance and testing will be conducted across enclosures. Samples from birds, soil, and water will be collected periodically to assess whether the virus is still active in the environment.
The reopening will only be considered if the zoo records at least two consecutive rounds of negative test results following the last positive detection. Typically, four rounds of testing are carried out at 15-day intervals, which means the closure could last well over a month if no further infections are detected.
Meanwhile, disinfection drives will continue, and staff will adhere to biosecurity rules strictly. Visitors will not be allowed until the environment is deemed completely safe.
Broader Public Health Concerns
The outbreak has reignited discussions on zoonotic diseases—illnesses that spread from animals to humans. Over the past two decades, viruses such as SARS, avian influenza, and more recently COVID-19, have highlighted the dangers of unchecked interactions between wildlife and humans.
While there is currently no evidence of human infections linked to the zoo incident, health experts urge caution. They advise people to avoid handling dead or sick birds in their surroundings and report such cases to local authorities immediately. Poultry farmers in and around Delhi are also being monitored closely, as cross-transmission between wild birds and domestic fowl remains a risk.
The Way Forward
For now, the zoo remains under lockdown, and the priority is to ensure no further spread of the H5N1 virus. Teams will continue to collect and test samples, while veterinarians closely monitor the health of animals across the facility.
Experts emphasize that transparency and vigilance are key. Regular updates are expected, and only when authorities are confident that the risk has been eliminated will the zoo reopen its gates to the public.
H5N1 Bird Flu Virus: What To Know
The detection of H5N1 bird flu in two painted storks at Delhi Zoo has prompted swift action, including an indefinite closure to visitors and the implementation of strict biosecurity measures. While the move is precautionary, it underscores the ongoing vulnerability of both wildlife and humans to zoonotic diseases.
As the situation unfolds, Delhi Zoo’s closure serves as a reminder of the delicate balance between conservation, public health, and the challenges posed by emerging infectious diseases. The next few weeks will be crucial in determining the extent of the outbreak and the timeline for the zoo’s reopening.
