USA: Avian Influenza Outbreaks: Preventive Measures and Risk Assessment

Avian influenza, commonly known as bird flu, is an infectious disease caused by influenza A viruses that affect birds, both domesticated and wild. The United States is currently experiencing a surge in bird flu outbreaks, with the number of affected birds in 2022 nearing record levels. Since early 2022, more than 49 million birds in 46 states have been infected with the virus or have been culled due to exposure to infected birds.

The current outbreak is already more widespread than the largest bird flu outbreak on record, which occurred in 2015, affecting 50.5 million birds in 21 states. While the risk to the general public from the current bird flu outbreaks remains low, it is important to take preventive measures to avoid spreading the virus to people or other birds/poultry and animals.

Preventive Measures to Avoid Bird Flu Infection

To prevent bird flu infection, it is essential to avoid unprotected contact with wild or domestic birds and poultry that appear sick or have died. Close and prolonged contact with infected birds or surfaces contaminated with bird flu viruses is the most common way that people get infected with the virus.

If contact with infected birds or poultry cannot be avoided, people should take precautions such as wearing personal protective equipment (PPE) like disposable gloves, boots, an N95 respirator, or a surgical mask, and eye protection. PPE recommendations from the Centers for Disease Control and Prevention (CDC) and the U.S. Department of Agriculture (USDA) are available for backyard flock owners. It is important to avoid touching your mouth, nose, or eyes during and after contact with birds or surfaces that may be contaminated with saliva, mucus, or feces from birds or poultry. Washing your hands with soap and water after touching birds or poultry is also important to prevent the spread of the virus.

For people who have backyard flocks or pet birds, it is important to take measures to keep them from becoming infected with bird flu virus. Infected birds shed avian influenza A viruses in their saliva, mucus, and feces, and susceptible birds can become infected through direct contact with infected waterfowl, other infected poultry, or contaminated surfaces. Avian influenza A viruses are highly contagious among birds, and some of these viruses can sicken and even kill certain domesticated bird species, including chickens, ducks, and turkeys.

Monitoring and Risk Assessment

The CDC has been monitoring illness among people exposed to bird flu virus-infected birds since the outbreaks were first detected in U.S. wild birds and poultry in late 2021. Bird flu viruses have been found in U.S. commercial and backyard poultry in 44 states and in wild birds in 46 states since early 2022. The CDC has tracked the health of more than 5,190 people with exposures to bird flu virus-infected birds, with only one reported case of bird flu virus infection.

The CDC continues to monitor the current situation and risk to the general public. While sporadic human infections with bird flu viruses in the U.S. resulting from close contact with infected birds/poultry would not be surprising given past human infections that have occurred in other countries after exposure to infected birds, this would not significantly change the CDC’s risk assessment. However, if person-to-person spread with this virus were to occur, that would raise the public health threat. Note that sustained person-to-person spread is needed for a pandemic to occur. Therefore, it is crucial for people to continue taking precautions around infected and potentially infected birds/poultry to help reduce the risk of bird flu virus infections in people.

Older Post Newer Post