The Centres for Disease Control and Prevention stated Wednesday that a person in Louisiana has had the first serious sickness caused by avian flu in the United States. Officials discovered that the patient had been exposed to sick and dead birds in backyard flocks, but an inquiry into the source of the infection in the state is still underway. This is also the first case of H5N1 bird flu in the United States associated with exposure to a backyard flock, according to a news release. Officials have not revealed the patient’s symptoms.

The Centres for Disease Control and Prevention stated Wednesday that a person in Louisiana has had the first serious sickness caused by avian flu in the United States. Officials discovered that the patient had been exposed to sick and dead birds in backyard flocks, but an inquiry into the source of the infection in the state is still underway. This is also the first case of H5N1 bird flu in the United States associated with exposure to a backyard flock, according to a news release. Officials have not revealed the patient’s symptoms.

Health officials verified the case on Friday, bringing the total number of recorded H5 bird flu cases in the United States to 61. Another severe case of H5N1 has been reported in a youngster from British Columbia. According to a release from the Louisiana Department of Health on Wednesday, the patient, who lives in southwestern Louisiana, is currently in the hospital. Until now, H5N1 instances in the United States have been minor, with conjunctivitis and upper respiratory symptoms. “While the current public health risk for the general public is low, people who work with birds, poultry or cows, or have recreational exposure to them, are at higher risk,” according to the state’s health agency.

Mild infections have been reported in dairy and poultry workers who had close contact with affected animals. In two cases, no known cause of the illnesses has been established, raising concerns among infectious disease experts about the prospect of human-to-human transmission, which might result in a pandemic.