A Missouri person has been infected with avian influenza despite having no contact with animals, the Centers for Disease Control and Prevention announced Friday.
The adult was hospitalized on Aug. 22 and has since recovered, but he remains the first case in the country of someone infected without contact with poultry or dairy cows, further raising public anxiety about the virus.
The CDC assured the public that risk “remains low.”
“The question now is, how did this patient become infected?” said Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Nashville. He told NBC News“It needs to be a very thorough investigation.”
The Missouri patient is only the 14th case of H5N1 avian influenza in the United States this year, but the virus has been confirmed in at least 196 dairy herds in 14 states since it was first reported in March. According to CDC data.
Outbreaks in poultry have been confirmed in 48 states.
Outbreaks of the disease have been reported among cattle in Missouri, but commercial and home chicken flocks have also been infected with the virus, the CDC said.
There is no evidence yet that this latest strain of bird flu is spreading from person to person.
Schaffner told NBC News that samples from the Missouri patient will need to be studied in a lab to see if the virus has mutated in a way that makes it easier to spread from person to person.
“The findings are particularly important given the lack of clear animal exposure at this time,” the CDC said in a statement Friday. “It is important to note that, although rare, there have been new cases to date. [bird flu] If it is not possible to determine whether the product is of animal origin.
Missouri Health Officials said in a separate news release. The state is not seeing any signs of unusual influenza activity among its residents, such as increased emergency room visits or laboratory detection of human influenza.
According to state officials, samples from the infected patients were sent by the Missouri State Public Health Laboratory to the CDC for additional testing.
The patient, who has pre-existing medical conditions, has been released from hospital and is recovering at home.
There has been no confirmed transmission of the virus among the patient's close associates.
