Vandalur Zoo shut for two days after H5N1 bird flu confirmed in water birds

Arignar Anna Zoological Park in Vandalur will remain closed to visitors on October 22 and 23 as a precautionary measure after H5N1 avian influenza was confirmed in water birds at the zoo, officials said.

The confirmation was made by the National Institute of High Security Animal Diseases (NIHSAD), Bhopal. According to Forest Department officials, seven water birds died at the zoo between October 3 and 7. Four were painted storks, one was a grey pelican, one a grey heron and one an oriental darter.

Zoo authorities cordoned off the area after the first bird died on October 3. They carried out disinfection, sanitisation and strict biosecurity protocols in line with Government of India guidelines, officials said. The zoo remained open at that stage because no further bird mortality or sickness was reported after October 9.

With the H5N1 confirmation now recorded, the zoo management is required to follow the Centre’s protocols. The two-day closure has been ordered to allow intensive sanitisation, stronger biosecurity and close monitoring of the situation. The public has been asked to cooperate with the precautionary measures, a press release from the zoo said.

Avian influenza is a viral infection that mainly affects birds. H5N1 is one subtype of the virus, and water birds are among the species that can carry and spread it. Because the zoo holds captive birds, including water birds, officials are applying animal-health protocols designed to prevent further transmission within the premises.

Outbreaks in captive birds require rapid containment because the virus can spread through contact with infected birds, contaminated water, feed, equipment and human movement. For this reason, the protocol separates teams and restricts movement between infected and healthy enclosures.

The action plan for prevention, control and containment of avian influenza sets out several steps once the infection is confirmed. Visitor entry must be stopped immediately. The movement of veterinarians and labourers is to be restricted, and they should not move from infected pens to healthy pens. Healthy sheds are to be managed by a separate team.

Officials are also required to sample the maximum possible number of birds. While sampling a water body, birds arriving at different locations are to be taken into account, and different species should be represented proportionately. In addition to bird samples, environmental samples such as water and soil are to be collected and sent for testing.

The control actions are the same as those for domestic poultry. However, endangered and precious captive birds confirmed as non-infected may be exempted from culling, officials said.

Under the protocol, sampling must be repeated every 15 days for at least four rounds. The zoo can be considered for reopening to the public only if two consecutive samplings after the last positive result are found negative, and the competent authority approves it.

The zoo has asked visitors to avoid the premises on the two days and to follow official announcements. The measure is aimed at reducing human movement around enclosures while disinfection and sampling are under way, the release said.

The closure is temporary, officials said, and is meant to protect visitors, staff and the captive bird population while the required checks are completed. The zoo has not reported any further bird mortality or sickness since October 9, according to the officials. Further decisions will depend on the results of the monitoring and sampling exercise.