WHO Reports Human Case Of H9N2 Bird Flu In India, Four-Year-Old In West Bengal Tests Positive

The World Health Organisation has identified a case of human infection of the H9N2 bird flu virus with a four-year-old child in West Bengal testing positive.

The child was admitted to the ICU in February after experiencing severe respiratory issues, high fever, and abdominal cramps. Following three months of treatment, the child was discharged.

It was revealed that the patient had been exposed to poultry both at home and in the surrounding environment. However, no other individuals among family or contacts were reported to have symptoms of respiratory illness, news agency Reuters stated.

Although the H9N2 virus typically causes mild illness, the WHO cautioned that sporadic human cases could arise as it is one of the most prevalent avian influenza viruses circulating among poultry in various regions.

This marks the second human infection of H9N2 bird flu in India, with the first case reported in 2019. The earlier case was also reported in a child, hailing from Maharashtra.

The case was detected during a community-based surveillance study in 93 villages of the Korku tribe in the Melghat district of Maharashtra in February 2019. During this study, health workers detected the A(H9N2) virus infection in an 18-month-old boy, who had shown symptoms including fever, cough, breathlessness, and difficulty in feeding. The child was fully immunised and treated.

The child had no contact with poultry. A week before displaying symptoms, he had accompanied his parents to a religious gathering. Similarly, the father exhibited comparable symptoms but was unable to undergo serologic testing.

Human cases of avian influenza stem from exposure to infected poultry or contaminated environments. Typically, human infections result in mild clinical symptoms. Given the continued detection of the virus in poultry populations, further human cases are anticipated. However, no clusters of cases have been reported, as per the World Health Organisation.

Presently, available evidence suggest the virus has not developed sustained transmission among humans. Therefore, the risk of human-to-human spread remains low. In the event that infected individuals from affected areas travel internationally, their infection may be identified in another country either during travel or upon arrival. However, widespread community-level transmission is unlikely as the virus has not acquired the capability for efficient human-to-human transmission, WHO said.