Earlier this month, a dairy worker in Texas tested positive for bird flu, also known as avian influenza, amid an outbreak of the virus among dairy cattle. This is the first time the highly pathogenic H5N1 strain of bird flu has been detected in cows, leading to the first documented cow-to-human transmission of an avian influenza virus in the United States. While this may sound alarming, the risk to the general public is low as health officials are closely monitoring the situation.
Bird flu is caused by infection with avian influenza type A viruses that naturally occur among wild aquatic birds and domestic poultry. While these viruses can occasionally infect other mammalian species, such as pigs, horses, bats, and dogs, they rarely spread to humans. However, recently there has been an increase in infections in cattle, with the H5N1 strain causing severe and often fatal disease in birds. The current outbreak of highly pathogenic H5N1, affecting cows, has spread to over a dozen dairy farms across the country.
Highly pathogenic avian influenza viruses have been detected in the U.S. in wild aquatic birds, commercial poultry, and backyard bird flocks, with cases reported in 48 states. The current outbreak of H5N1 affecting cows has spread to eight states, including Texas, Kansas, Michigan, New Mexico, Idaho, Ohio, North Carolina, and South Dakota. Surveillance efforts are increasing, leading to the discovery of more cases among cattle that would have previously gone undetected.
Avian influenza viruses can spread from infected birds to humans through direct contact, contaminated environments, or intermediate hosts. Infected birds can shed the virus in their secretions and people can become infected if the virus enters their mouth, nose, eyes, or is inhaled. While there have been rare cases of human-to-human transmission, the virus does not have the genetic capacity to spread easily between people. Consuming properly cooked food, including eggs, chicken, beef, and pasteurized milk, is believed to be safe and not associated with bird flu infection.
In cases where humans do contract bird flu, symptoms can range from mild to severe, with some individuals remaining asymptomatic. While it can be a serious infection with a high mortality rate, antiviral medications can be used to treat the virus. Symptoms of bird flu may include fever, cough, runny nose, body aches, headache, fatigue, shortness of breath, eye redness, diarrhea, and nausea. Recovery from bird flu is possible with appropriate treatment and care.
To prevent the spread of bird flu, the CDC recommends avoiding visits to poultry farms if possible, wearing a mask and avoiding touching birds in such environments, practicing good hand hygiene, and avoiding contact with sick or dead birds. Properly cooking and handling poultry products can reduce the risk of infection, and individuals should seek medical attention if they become sick after contact with birds. While the risk of contracting bird flu is low, it is important to remain vigilant and take preventive measures in high-risk situations.