The CDC on Dec. 18 confirmed a patient in Louisiana has been hospitalized with a severe bird flu infection, marking the first human case of severe illness tied to the H5N1 virus in the country.
The patient was exposed to sick and dead birds in backyard flocks, though officials with the Louisiana health department are still investigating to confirm the source of infection.
The CDC reiterated that there has been no evidence of person-to-person spread, and that the overall risk the bird flu poses to the public remains low.
Four more notes:
1. The agency did not include any details regarding the individual's symptoms in its Dec. 18 statement, though officials with the Louisiana health department told CNN that the patient is experiencing severe respiratory disease. The individual is older than 65 and has underlying medical conditions that elevate their risk of flu complications.
2. This marks the the first U.S. case of H5N1 linked to exposure to a backyard flock. Since April, there have been 61 reported human cases of H5 bird flu, mostly among individuals who work with dairy cattle and poultry. Most U.S. patients with a confirmed case have reported mild symptoms.
"This case underscores that, in addition to affected commercial poultry and dairy operations, wild birds and backyard flocks also can be a source of exposure," the CDC said.
3. The H5N1 outbreak has affected more than 850 dairy herds in 16 states since late March, according to the CDC.
4. While federal health officials have emphasized that the risk to public health remains low and that there is no indication that person-to-person spread is occurring, experts have raised concern that the nation is not conducting enough testing to quickly identify if and when that does occur. Surveillance has been difficult, in part because of understaffing across state health departments and hesitancy among farm workers to share information with state officials, the CDC said.