Person in Mexico dies after contracting avian influenza, WHO says

HQ Team

June 6, 2024: A 59-year-old person in Mexico died in April after contracting avian influenza A(H5N2) virus, the first such death in the country, according to the World Health Organization.

The confirmed case was reported to the Pan American Health Organization, an agency of the United Nations in charge of international health cooperation in the Americas, on May 2024, according to a June 5 WHO statement.

“This is the first laboratory-confirmed human case of infection with an influenza A(H5N2) virus reported globally and the first avian H5 virus infection in a person reported in Mexico.”

“The person had no history of exposure to poultry or other animals. The case had multiple underlying medical conditions. The case’s relatives reported that the case had already been bedridden for three weeks, for other reasons, prior to the onset of acute symptoms.”

Fever, diarrhoea

The person developed fever, shortness of breath, diarrhoea, nausea and general malaise. The patient sought medical attention, was hospitalised at the National Institute of Respiratory Diseases “Ismael Cosio Villegas” (INER) on April 24 and died the same day due to complications of his condition.

Results from Real-Time Polymerase Chain Reaction (RT-PCR) of a respiratory sample collected and tested at INER on April 24 indicated a non-subtypeable influenza A virus. 

The sample was sent on May 8 for sequencing to the Laboratory of Molecular Biology of Emerging Diseases Center for Research in Infectious Diseases (CIENI per its acronym in Spanish) of INER, which indicated that the sample was positive for influenza A(H5N2).

Further tests conducted by the Institute of Epidemiological Diagnosis and Reference of the Mexico National Influenza Centre, showed a positive result for influenza A. On 22 May, sequencing of the sample confirmed the influenza subtype was A(H5N2).

No further cases were reported during the epidemiological investigation, according to the WHO statement.

‘Low risk’

In March 2024, a high pathogenicity avian influenza A(H5N2) outbreak was detected in a backyard poultry farm in Michoacán state, which borders the State of Mexico and where the case was residing.

During the same month, an outbreak of low pathogenicity avian influenza (LPAI) A(H5N2) was identified in poultry in Texcoco, State of Mexico, and a second outbreak of LPAI A(H5N2) in April in the municipality of Temascalapa in the same state. 

“Thus far, it has not been possible to establish if this human case is related to the recent poultry outbreaks.”

Avian influenza virus infections in humans may cause mild to severe upper respiratory tract infections and can be fatal. Conjunctivitis, gastrointestinal symptoms, encephalitis and encephalopathy have also been reported.

“WHO assesses the current risk to the general population posed by this virus as low.”