Influenza Virus


Influenza virus is an infectious agent that belongs to the virus family Orthomyxoviridae, causing a respiratory tract infection in vertebrates. The flu virus is an enveloped animal virus with an external phospholipids bi-layer membrane enveloping the viral genetic substance and the protein coat.

Types of influenza viruses

There are three (3) fundamental types of influenza virus: A, B and C. Influenza A virus infects humans and many different animals including chickens, ducks, whales, pigs, seals and horses. Influenza B virus circulate widely only among humans. Influenza type C is mostly found in humans, but has also been found in dogs and pigs. Generally, they trigger a minor respiratory sickness and are not believed to result in epidemics. The flu pandemics result from type A viruses, and are therefore the most-feared type of flu virus; none of types B or C have triggered pandemics. Influenza A can be split into sub-types based on the genes that make up the surface proteins.

What influenza viruses are made of?

The flu virus features a circular shape (even though it can be irregularly or elongated shaped) and possesses a spike layer on the outside. There are two (2) different kinds of spikes, each made of a different protein – one is the neuraminidase (NA) protein and the other is the hem agglutinin (HA) protein.

How flu viruses change?

Influenza virus is among the most changeable viruses known. They are constantly mutating and changing, and they are unpredictable. These changes can happen slowly over time or suddenly. Sometimes, these mutations lead to viruses that move from animals to humans. Influenza viruses can mutate in two diverse ways:

Antigenic drift: These are slight changes in the genes of flu viruses that happen slowly over time as the virus multiplies. This causes the changes to the seasonal influenza that require us to get vaccinated against the flu every year.

The other type of change is called the antigenic shift. This is a sudden, major change that occurs when two (2) different influenza strains merge to infect the same cell. This change is what makes it possible for influenza virus to move from animal to humans. Whenever shift happens, the majority of individuals have little if any resistance against the brand new virus. Whilst flu viruses are transforming by antigenic drift constantly, antigenic shift occurs only occasionally.

The recommended technique to stop the prevalent infection and high death rate that a newly formed flu virus can inflict on us is to be vaccinated. With that, the human immune body system would be ready to combat an infection.