GENEVA: A person died of bird flu in Mexico in the first confirmed case of a human infected with the H5N2 variant, the World Health Organisation has said.
The 59-year old, who died on April 24 after developing fever, shortness of breath, diarrhoea and nausea, had “no history of exposure to poultry or other animals” and “multiple underlying medical conditions”, the WHO said in a statement.
“Although the source of exposure to the virus in this case is currently unknown, A(H5N2) viruses have been reported in poultry in Mexico,” WHO said in a statement.
But how this individual got infected “is a big question mark that at least this initial report doesn’t really address thoroughly.”
WHO said the current risk of bird flu virus to the general population is low.
The resident of the State of Mexico was hospitalised in Mexico City and died the same day, the statement said.
It was the “first laboratory-confirmed human case of infection with an influenza A(H5N2) virus reported globally”, the WHO added.
Mexican health authorities reported the confirmed case to the UN health body on May 23 after conducting laboratory tests.
The source of exposure to the virus was unknown, the WHO said, although cases of H5N2 have been reported in poultry in Mexico.
H5N2 cases were detected in a backyard poultry farm in Michoacan state in March, with other outbreaks identified in the State of Mexico, according to the UN health body.
Chronic kidney disease, type 2 diabetes
But it said establishing a link between the human case and the poultry infections was so far impossible, estimating the risk to people as “low”.
Mexico’s health ministry said in a statement that the person who died was “a 59-year-old man with a history of chronic kidney disease, type 2 diabetes, (and) long-standing systemic arterial hypertension”.
“There is no risk of contagion for the population,” the statement said, adding that “all samples from identified contacts (of the patient) have been negative”.
Authorities are monitoring farms near the victim’s home and have established a permanent monitoring system to detect other cases in wildlife in the area, the statement added.
A different variant of bird flu, H5N1, has been spreading for weeks among dairy cow herds in the United States, with a small number of cases reported among humans.
But none of the cases are human-to-human infections, with the disease instead jumping from cattle to people, authorities have said.
Bird flu has infected mammals such as seals, raccoons, bears and cattle, primarily due to contact with infected birds.
Scientists are on alert for changes in the virus that could signal it is adapting to spread more easily among humans.
The United States has reported three cases of H5N1 human infection after exposure to cows since an outbreak was detected in dairy cattle in March. Two had symptoms of conjunctivitis, while the third also had respiratory symptoms.
Although the death in Mexico was not the same strain as the one that is currently infecting cattle in the United States, they are both H5 avian viruses.
Pekosz said that since 1997, H5 viruses have continuously shown a propensity to infect mammals more than any other avian influenza virus.
“So it continues to ring that warning bell that we should be very vigilant about monitoring for these infections, because every spillover is an opportunity for that virus to try to accumulate those mutations that make it better infect humans,” Pekosz said.
Australia reported its first human case of A(H5N1) infection in May, noting there were no signs of transmission. It has however found more poultry cases of H7 bird flu on farms in Victoria state.