Difference Between Antigenic Shift and Drift

Antigenic drift involves the accumulation of a series of minor genetic mutations. Antigenic shift involves “mixing” of genes from influenza viruses from different species. Pigs, birds, and humans.

What is the difference between shift and drift?

Influenza strains are constantly mutating. A small change to the genetic makeup of influenza strains is referred to as antigenic drift, while a major change is called antigenic shift.

Is antigenic drift the same as genetic drift?

Antigenic drift should not be confused with antigenic shift, which refers to reassortment of the virus’ gene segments. As well, it is different from random genetic drift, which is an important mechanism in population genetics.

What is antigenic drift?

antigenic drift, random genetic mutation of an infectious agent resulting in minor changes in proteins called antigens, which stimulate the production of antibodies by the immune systems of humans and animals. These mutations typically produce antigens to which only part of a population may be immune.

What is the best example of an antigenic shift?

An example of a pandemic resulting from antigenic shift was the 1918-19 outbreak of Spanish Influenza. This strain was originally the H1N1 avian flu, however antigenic shift allowed the viral infection to jump from pigs to humans, resulting in a large pandemic which killed over 40 million people.

What does hemagglutinin and neuraminidase do?

Hemagglutinin-neuraminidase (HN) protein, which is responsible for virus attachment, interacts with the fusion protein in a virus type-specific manner to induce efficient membrane fusion.

Why does antigenic drift occur?

Antigenic drift: A subtle change in the surface glycoprotein (either hemagglutinin or neuraminidase) caused by a point mutation or deletion in the viral gene. This results in a new strain that requires yearly reformulation of the seasonal influenza vaccine.

What causes antigenic drift?

20 Antigenic drift is caused by point mutations in the HA and NA genes that are driven by immune pressure and the infidelity inherent in the replication of RNA genomes.

What is the meaning of antigenic?

Listen to pronunciation. (AN-tih-jen) Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body.

Does antigenic shift occur in rotaviruses?

Aside from showing different G and P types and an extensive variety of combinations therein, rotaviruses can accumulate point mutations leading to antigenic drift, reassortment of genome segments to drive antigenic shift, and zoonotic transmission of animal strains to introduce new antigenic types into humans.

Where does antigenic shift occur?

Antigenic shift or reassortment variations occur only in influenza A viruses, which are sudden and complete changes in one or both surface antigens. This results completely in new viruses having surface antigens different from the antigens of the old viruses circulating in the population.

When does antigenic shift occur?

Antigenic shift

This may happen when two different influenza viruses infect a cell and the genome segments are exchanged during replication.

What happens during antigenic shift?

Antigenic shift is the process by which two or more different strains of a virus, or strains of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains.

What is an antigenic shift biology?

antigenic shift, genetic alteration occurring in an infectious agent that causes a dramatic change in a protein called an antigen, which stimulates the production of antibodies by the immune systems of humans and other animals.

What is the difference between recombination and reassortment?

Reassortment only occurs in segmented RNA viruses, whereas recombination stricto sensu occurs in virtually all RNA viruses. The formation of a hybrid RNA sequence after inter-molecular exchange of genetic information between two nucleotide sequences results specifically from the latter.

Is antigenic shift a mutation?

The family Orthomyxoviridae is well known for containing influenza viruses with a segmented RNA genome that is prone to gene reassortment in mixed infections (known as antigenic shift) resulting in new virus subtypes that cause pandemics, and cumulative mutations (known as antigenic drift), resulting in new virus

Which influenza pandemic was notable for an antigenic shift from H2N2 to H3N2?

The 1968 pandemic was caused by influenza A/Hong Kong/1968 (H3N2) virus. This pandemic virus contained two genes derived from a low-pathogenicity avian influenza A virus and six genes from the A(H2N2) virus that had been circulating among people since its emergence to cause the 1957 H2N2 pandemic.