With a considerable number of victims, from 80 to 100 million, since 1918, influenza is considered one of the most pandemic diseases of all time. There are three types of influenza viruses: influenza A virus, influenza B virus, and influenza C virus. It is a subtype of the Orthomyx-ovirid virus family. Types B and C do not cause pandemic disease, while type A does. Type A is classified into three main subtypes H1.N1, H1.N2 and H3.N2. The (HN) refers to the two types of proteins present on the surface of the virus (hemagglutinin and neuraminidase). The difference in numbers is due to the difference in protein variability. The H1.N1 virus, widely known as the Spanish flu, is the only type capable of transmitting from human to human. H5.N1, or "bird flu", is not transmitted between humans, but it occurs in a few cases when it evolves. Avian flu appears to be the same as Spanish flu, but in a new arrangement, meaning that certain changes must occur in the virus in order for it to be transmitted between humans. Apparently we are misunderstanding the mechanism by which the virus works and so it has re-emerged. To reduce the damage caused by these viruses, we need to understand the structure and mechanism of spread of the virus. The H5.N1 virus has been transmitted to humans since 1997. We all know that the virus is made up of 16 genes which constitute a small unit composed of RNA (ribonucleic acid) which carry all the characteristics from one generation to the next. other. These viruses are adopted into the genome of birds such as ducks. These animals are considered the natural host of these viruses, meaning that the birds' immune system recognizes the virus as a normal organism. According to Debora Mackenzie in News Scientists, before 2003, the virus began to spread in chicken farms in East Asia. They discovered... middle of paper...... everything that could pose a potential threat. Avian flu certainly poses a potential threat. There are many ways to protect our body, for example a vaccine which is a substance given to people to strengthen their immune system. Sometimes it can be dead cells from the virus – the virus outside the body is not a living organism, so it must be at its weakest point. Additionally, there are certain precautions and procedures that we must follow that work alongside medical methods. Dr. Jeffery Greene, in his book on the avian flu pandemic, points out that the best way to combat such viruses is to deter its characters and its carrier. The flu virus dies at high temperatures (167-212°F). It is also destroyed by chemicals such as alcohol, detergents and bleach. We also need to be careful in public places because all the germs hiding on surfaces