CDC: Tests on Marin illness negative for bird flu

Tests on a child who fell ill in Marin County after drinking raw milk showed no H5N1 virus, also known as bird flu, according to the federal Centers for Disease Control and Prevention.

The patient, an out-of-state resident, visited Marin over the Thanksgiving holiday and suffered a fever and vomiting, according to county health officials. Initial state and local tests for bird flu were inconclusive, and the county sent a sample to the CDC for testing.

In the meantime, the county announced that the child had consumed unpasteurized milk before becoming sick. Authorities have advised the public to avoid raw dairy products because of avian flu outbreaks among cows exposed to infected birds.

However, the CDC tests showed no “flu A,” a category that includes both bird flu and seasonal flu, a spokesperson for the agency said Friday.

Nevertheless, Dr. Lisa Santora, the county’s public health officer, said bird flu has not been ruled out. She said a positive flu A test by a local public health lab was confirmed in a second test.

Santora said the question of avian flu will remain unresolved because of the low level of RNA in the child’s specimen.

“No further testing is available,” she said. “This will be classified as suspected case of avian flu due to consumption of contaminated raw milk.”

The standards for that classification come from the Council of State and Territorial Epidemiologists and the National Notifiable Diseases Surveillance System.

The child recovered and other family members were not sickened, the county said.

Thirty-four human cases of bird flu had been confirmed in the state as of Friday, according to the California Department of Public Health. Thirty-three of the cases involved exposure to cattle. In the other case, dairy cow exposure is suspected but tests had conflicting results.

Fifteen infections among wild birds have been detected in Marin County since October 2022, according to U.S. Department of Agriculture.

State and federal health officials say the H5N1 risk to the general public is low, but it has spread widely among wild birds, putting cattle and poultry at risk. Many of the people infected are agricultural workers.

Nationwide, 60 human cases have been confirmed, according to the most recent CDC data. Most have been linked to dairy cows, but 20 cases have been linked to poultry.

In the last 30 days, 339 new infections have been confirmed in dairy cows, including 338 cases in California, the CDC said.

Originally Published: December 13, 2024 at 11:36 AM PST