How did the influenza virus evolve?

How did the influenza virus evolve?

In fact, in a process called antigenic drift, flu evolves in response to the antibodies our bodies produce each year. During the course of a flu epidemic, many people gain immunity to the strain of the virus that is currently circulating.

How has influenza adapted?

Influenza viruses have high mutation rates and are constantly changing, which enables the virus to quickly adapt to changes in the host environment, as is the case during interspecies transmission. The rapid evolution results from two mechanisms: reassortment and point mutations (10).

What important role do pigs play in the evolution of influenza virus and infections in humans?

Genetic reassortment in pigs allows for the generation of novel influenza viruses and further demonstrates that pigs can serve as intermediate hosts and therefore as “mixing vessels” for human, swine and avian influenza viruses.

How do viruses adapt to their environment?

Viruses adapt to their hosts by evading defense mechanisms and taking over cellular metabolism for their own benefit. Alterations in cell metabolism as well as side-effects of antiviral responses contribute to symptoms development and virulence.

Did the H1N1 virus mutate?

These extinctions appear to be due to a continuous accumulation of mutations. At the time of its disappearance in 2009, the human H1N1 lineage had accumulated over 1400 point mutations (more than 10% of the genome), including approximately 330 non-synonymous changes (7.4% of all codons).

Why are scientists concerned about the h5n1 flu virus?

Because influenza viruses have the capacity to mutate, or undergo changes in their surface proteins, scientists are concerned that the bird flu viruses may eventually change into forms of the virus that are able to infect humans more easily.

Why is influenza virus having extremely high mutation rate?

It is well known that the influenza viral RNA-polymerase represents the lack of proofreading function. Thus, the integration of faulty nucleotides often occurs during the viral replication process with a rate of 10−3 to 10−4, which results in high mutation rates [39,40].

Can pigs get bird flu?

They now report that between 2005 to 2007 when the avian flu peaked, 7.4 per cent of 700 pigs they tested also carried H5N1. There have been sporadic reports of H5N1 in pigs, but this is the first time the extent of the problem has been measured.

What supports the argument that viruses are nonliving?

Some scientists have argued that viruses are nonliving entities, bits of DNA and RNA shed by cellular life. They point to the fact that viruses are not able to replicate (reproduce) outside of host cells, and rely on cells’ protein-building machinery to function.