What is an antigenic shift?

Antigenic shift is one of the methods that some viruses use to develop and leak the attention of the body's immune system. An antigenic shift occurs when a new host species is exposed to a viral trunk that has not yet seen, through the transmission of species and species and through the conversion of genetic material. The new host's immune system does not recognize this virus efficiently, because the antigens present on the virus differ from previous viruses that the host was exposed to. This process is most studied at the flu and is an important factor in the development of new epidemic influenza subtypes.

Antigenic shift can be described in one of three ways. Two viruses infecting the same cell can produce gene segments that mix to form a new viral strain. The virus circulating on a particular species can jump directly to the new animal host. Alternatively, for example, a bird virus can jump to a pig host and then on a human host.

Influenza virus has three types, A, A, D C. Of these tYPs cause flu and only influenza disease through global infections. Influenza and has two sets of main antigens, neuraminidases (N) and hemagglutinin (H), on the outside of viral capsules. These are antigens that recognize the immune system and use to target the destruction virus. The anti -shift viral art means that the virus can be exchanged around these antigens to create a new virus during the replication that does not initially recognize the immune system.

For example, the 2009 H1N1 pandemic was caused by a viral subtype with antigens H1 and N1. It is believed that this influenza virus came from the genetic re -evaluation of two different swine flu viruses in a pig cell. The US Centers for Control and Prevention of Diseases said that this new flu also had genes of bird and human tribes, but that these genes probably circulated in pigs for decades Predandemia inthe result of the previous antigenic shift. After the antigenic shift of the pig through genetic re -evaluation, the virus then jumped to infect people.

The

antigenic shift process should not be confused with other methods of viruses that are used to change antigens called antigen drift. An antigenic drift is a gradual mutation of influenza genes that slightly change the product of genes. The antigenic drift causes slight differences in viral particles that can also cause the immune system to effectively recognize the virus.