The United States, like many other parts of the world, is currently grappling with the ongoing threat of highly pathogenic avian influenza (HPAI) virus outbreaks in both wild birds and poultry. This particular influenza virus belongs to type A, subtype H5N1, commonly known as avian or bird flu.The H5N1 subtype has been present among birds and poultry across the globe for several years and continues to evolve into different clades. The current clade, 184.108.40.206b, was first detected in wild birds in the U.S. in January 2022, leading to poultry outbreaks in 47 states and affecting more than 58 million commercial poultry and backyard flocks.
While human cases are still rare, with less than 10 reported globally since December 2021, health officials are concerned about the growing number of reports in mammals, given that the circulating H5N1 strain has characteristics that make it more recognizable to mammal airway cells. On February 8, Dr. Tedros Adhanom Ghebreyesus of the World Health Organization (WHO) stressed the importance of monitoring the situation closely.
H5N1 first emerged in southern China in 1996 and caused 18 human infections during a large outbreak in Hong Kong in 1997. Despite containment efforts, the virus persisted in birds and re-emerged in 2003, spreading widely across Asia, Africa, Europe, and the Middle East. These outbreaks resulted in both poultry and sporadic human infections. Over the past 20 years, the World Health Organization (WHO) has reported more than 860 human infections with H5N1 bird flu viruses in over 17 countries.
H5N1 is primarily transmitted among birds through the exchange of respiratory secretions such as droplets of saliva, nasal mucus, and feces. Human infections can occur when the virus enters a person's body (through the eyes, nose, or mouth), or by inhaling contaminated particles in the air. This can happen when the virus is present in the air in droplets or possibly dust or when a person touches a contaminated surface and then touches their face without washing their hands first.
How to protect ourselves:
The symptoms of H5N1 infection in humans can range from fever, cough, sore throat, muscle aches, and breathing difficulties to more severe symptoms such as diarrhea, vomiting, abdominal pain, and bleeding from the nose and gums. H5N1 can cause severe respiratory illness, pneumonia, and organ failure, and it can be fatal. Early detection is crucial to successful treatment.
As the world continues to navigate the COVID-19 pandemic, it is essential not to forget about other potential health threats and take measures to protect ourselves and our communities. Stay informed and stay safe.