Health officials announced Friday that four more health care workers in Missouri are experiencing mild respiratory symptoms after coming into contact with avian influenza patients.
A total of six healthcare workers have now developed symptoms after coming into contact with patients, making this the first confirmed case of the disease without known animal exposure.
Although the patient recovered, the case raises questions about the possibility of human-to-human transmission of avian influenza, which primarily affects animals.
The Centers for Disease Control and Prevention said the only employee tested for the virus returned a negative result.
The employee underwent a PCR test for the virus, had what was considered high-risk contact with a patient, and subsequently developed mild symptoms.
Another high-risk contact and three other low-risk contacts did not get tested while exhibiting symptoms, the CDC said.
“At the time these people’s previous symptoms were discovered, PCR tests would have been unreliable,” the agency said.
During the COVID-19 pandemic, PCR tests, which provide quick results, have become commonplace.
In addition to the health care worker, a family member of the patient also developed symptoms but was unable to get tested, according to the CDC.
The CDC said all symptomatic health care workers and household contacts provided blood samples for antibody testing.
The results of those tests remain unknown.
Avian influenza, also known as avian influenza, rarely infects humans. Fourteen people have contracted the viral disease in the United States so far this year.
Missouri’s response to the only known animal exposure has come under intense scrutiny.
Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, said he was concerned about how long it took Missouri to figure out who else may have been infected from the first patient. told health publication STAT.
“Public health trust is really at risk here,” Osterholm said.
Thirteen other cases in 2024 involved farm workers linked to avian influenza outbreaks on dairy farms or poultry farms.
The CDC continues to warn that the risk to the general public remains low.
However, the United States has seen an increase in bovine avian influenza cases this year.
Cattle in 14 states have been affected since the outbreak was first reported in March, according to the CDC.
