The first serious human case of bird flu has been reported in the United States

The Centers for Disease Control and Prevention (CDC) has reported the first serious human case of bird flu in the United States.

The U.S. Centers for Disease Control and Prevention said in a statement Wednesday that the patient, from Louisiana, was confirmed to be infected with the H5N1 bird flu virus on December 13. At this time, the investigation into the source of his infection is still ongoing, but it can be confirmed that the patient had contact with sick and dead birds kept on private backyard farms.

This is the first human case of H5N1 in the United States associated with a private backyard farm.

Preliminary genetic analysis showed that the patient was infected with the avian influenza virus type D1.1. The U.S. Centers for Disease Control and Prevention is conducting further genome sequencing of the virus samples.

Since April this year, 61 human cases of H5 avian influenza virus have been reported in the United States.

The CDC noted that no human-to-human transmission of the H5 avian influenza virus has been detected, and the immediate risk to public health from H5N1 avian influenza remains low, but reminded the public to avoid contact with sick or dead animals, especially wild birds and poultry.

Separately, Southern California Governor Gavin Newsom declared a state of emergency Wednesday after cases of bird flu were found in dairy cattle on a farm, but stressed it was a precautionary measure to ensure government agencies have the resources and flexibility they need to respond to the outbreak.

Newsom's office said there had been no reported cases of human-to-human transmission in California, and that the cases had been among people who had contact with infected dairy cattle.