What are the types of bird flu? (H5N1, H7N9, etc.)

  Avian flu is a type of infectious disease that primarily affects birds, but some strains can also infect humans and other animals. Depending on the strain of the virus, avian flu can have different effects on bird and human health.

  Scientists classify influenza viruses based on two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N). On this basis, influenza viruses are divided into different types, such as H1N1, H3N2, H5N1, H7N9 and others. Below are some of the most important types of AI that can also affect humans.

   H5N1

  The H5N1 strain is the best known and one of the most deadly types of bird flu. It was first identified in humans in Hong Kong in 1997, and has since spread to various parts of the world. The H5N1 virus is particularly deadly to birds, but can transmit to humans, leading to serious illness and high mortality rates.

   H7N9

  The recently identified H7N9 strain is another that is both fatal to birds and capable of infecting humans. The first human cases were reported in China in 2013. Although H7N9 does not appear to transmit easily from person to person, several cases of humans being infected by the virus have been fatal.

   H1N1

  The H1N1 avian flu is closer to the seasonal flu we know from everyday experience. This strain of flu virus is capable of infecting people and is responsible for the 1918 flu pandemic (known as "Spanish flu") and the 2009 flu pandemic.

   H3N8

  The H3N8 strain is mostly known as the equine influenza virus, but it has also accounted for a few cases of infection in dogs. Although no H3N8 infections have been found in humans to date, scientists are monitoring this strain, keeping an eye out for any signs that may indicate its ability to infect humans.

   H7N3

  The H7N3 virus is particularly harmful in poultry. Although it is rarely found in humans, there are cases where it has happened in the past, especially among people who have had direct contact with infected birds.

  In summary, there are many types of avian influenza virus that can pose a risk to humans. Most of them do not transmit easily from person to person, but pose a potential threat, especially if the virus mutates and gains the ability to transmit effectively between people. As a result, scientists around the world are constantly monitoring avian influenza viruses and working on effective strategies to prevent and treat the disease.