A person in Missouri has been diagnosed with bird flu — despite never coming into contact with any animals, the Centers for Disease Control and Prevention announced on Friday.
The adult, who was hospitalized on Aug. 22, has recovered, however the case adds to growing national anxiety about the virus as the patient is the first in the country to contract the disease without contact with poultry and dairy animals.
The CDC assured that the risk among the general public “remains low.”
“The question now is: How did this patient acquire the infection?” Dr. William Schaffner, an infectious diseases expert at Vanderbilt University Medical Center in Nashville, told NBC News. “We need a very, very thorough investigation.”
While the Missouri patient is only the 14th person in the US to contract the H5N1 Bird Flu this year, at least 196 herds of dairy cows in 14 states have confirmed outbreaks of the virus since the outbreak was first reported in March, according to CDC data.
Outbreaks in poultry have been confirmed in 48 states.
Missouri has reported outbreaks of the disease among cattle, but commercial and backyard poultry flocks have contracted the virus, the CDC said.
There has been no evidence that this latest bird flu strain has been spreading from person to person.
The sample from the Missouri patient will need to be studied in the laboratory to see whether the virus might have mutated, making it easier for human to human transmission, Schaffner told NBC News.
“The results of this investigation will be particularly important in light of the current lack of an obvious animal exposure,” the CDC said in its announcement Friday. “It is important to note that, while rare, there have been novel [bird flu] cases where an animal source cannot be identified. “
Missouri health officials said in a separate news release that there has been no sign of unusual influenza activity among its residents, including no upticks in emergency room visits or laboratory detection of the human flu in the state.
A sample from the infected patients was sent from the Missouri State Public Health Laboratory to the CDC for additional testing, state officials said.
The patient, who has pre-existing health conditions, has been released from the hospital and is recovering at home.
No transmission of the virus has been identified among the patient’s close associates.
