WHO Says Comorbidities, Not Bird Flu, Caused Mexican Man’s Death, Changes Initial Report

A test tube labeled "Bird Flu" and eggs in a picture illustration on Jan. 14, 2023. Dado Ruvic/Illustration/Reuters

Mexican officials have determined that a man previously thought to have died from a rare bird flu instead died from other comorbidities, according to the World Health Organization (WHO).

The WHO initially reported on June 5 that in May a 59-year-old man was admitted to a hospital in Mexico City after having been “bedridden for three weeks,” and was diagnosed with a rare strain of bird flu called H5N2, marking the first “laboratory-confirmed human case” of this strain of bird flu infection globally and the first case reported in Mexico.

The strain is different from H5N1, which has affected livestock in the United States, infecting three dairy workers.

In April, the man—who reportedly had no contact with poultry or other animals—began to experience shortness of breath, diarrhea, nausea, and fever, the WHO said.

The WHO said that the source of exposure was unknown; however, there have been cases of bird flu in poultry in Mexico.

While the WHO considered his diagnosis a “high public health impact,” it assessed the risk to the public at the time was low.

On June 14, the WHO announced that after further investigation the man had died from underlying comorbidities.

The WHO said that a “multidisciplinary group of experts” that included intensive care professionals and pulmonologists investigated his cause of death and found that while he had been diagnosed with H5N2, it wasn’t the cause of death.

“No further cases were reported during the epidemiological investigation,” the WHO said. “The 17 contacts identified and monitored at the hospital where the man died and 12 additional contacts near his residence, were tested and the results were negative for influenza viruses.”

An outbreak of H5N2 was reported in poultry in Texcoco de Mora, Mexico, with a second outbreak occurring in the city of Temascalapa.

“Avian influenza virus infections in humans may cause mild to severe upper respiratory tract infections and influenza-associated deaths have been reported in persons with or without comorbidities,” the WHO said. “Conjunctivitis, gastrointestinal symptoms, encephalitis, and encephalopathy have also been reported.”

The Mexican Ministry of Agriculture and Rural Development said it began detecting bird flu on farms in Mexico in 2023, but determined that it posed no risk to humans because the farms are quarantined and the infected animals are killed.

‘Widespread in Wild Birds’

The U.S. Department of Agriculture (USDA) reported that since the bird flu outbreak began in February 2022, 96.91 million birds and 1,151 flocks have been infected.

“Of those, 496 flocks have been commercial, and 655 flocks have been backyard,” the USDA stated.

On June 12 in Lyon County, Minnesota, there was a report of 92,4000 commercial turkeys infected, the USDA reported.

According to the Centers for Disease Control (CDC), H5N1 has been “widespread in wild birds worldwide” and is leading to outbreaks in dairy cows and poultry.

Three Human Infections

In May, the CDC reported its third case of human bird flu infection associated with an outbreak in dairy cows.

“As with the previous two cases (one in Texas, one in Michigan), the person is a dairy farm worker with exposure to infected cows, making this another instance of probable cow-to-person spread,” the CDC said. “This is the first human case of H5 in the United States to report more typical symptoms of acute respiratory illness associated with influenza virus infection, including A(H5N1) viruses.”

In March, the USDA reported that the bird flu could be found in the raw milk of cattle infected by wild birds.

The USDA said, “Initial testing by the National Veterinary Services Laboratories has not found changes to the virus that would make it more transmissible to humans, which would indicate that the current risk to the public remains low.”