U.S. reports its first human case of H5 bird flu

Centers for Disease Control and Prevention (CDC) recently said that the first known human case of H5 bird flu in the United States has appeared in a person in Colorado.

About H5 Bird Flu:

• This is the second human case associated with this specific group of H5 viruses that are currently predominant, and the first case in the United States.
• The first case internationally occurred in December 2021 in the United Kingdom in a person who did not have any symptoms and who raised birds that became infected with H5N1 virus.
• More than 880 human infections with earlier H5N1 viruses have been reported since 2003 worldwide.
• However, the predominant H5N1 viruses now circulating among birds globally are different from earlier H5N1 viruses.
  

Avian influenza:

• Bird flu or avian influenza is a disease which is caused by avian influenza Type A virusesfound naturally in the wild birds worldwide.
• The virus can infect domestic poultry which includes chickens, ducks and turkeys.
• Avian Influenza type A viruseswhich are classified based on two proteins on their surfaces:
• Hemagglutinin(HA)
• Neuraminidase(NA)
• There are about 18 HA subtypes and 11 NA subtypes.
• Several combinations of these two proteins are also possible e.g., H5N1, H7N2, H9N6, H17N10, etc.
• The virus was first detected in geese in China in 1996.
• Symptoms of avian influenza: Fever, cough, sore throat, nausea, abdominal pain, muscle aches, diarrhea, vomiting Severe respiratory illness (respiratory distress, viral pneumonia, respiratory failure), Neurologic changes (altered mental status, seizures).
• Risk groups: Children and adults below 40 are seen to be the most affected and mortality was high in 10-19 years old.