What causes antigenic shift?
Antigenic Shift Shift can happen if a flu virus from an animal population gains the ability to infect humans. Such animal-origin viruses can contain HA or HA/NA combinations that are different enough from human viruses that most people do not have immunity to the new (e.g., novel) virus.
What is antigenic shift quizlet?
Antigenic Shift. abrupt change in a virus, which can cause a pandemic. Antigenic Drift. small genetic changes in a virus, so eventually the bodies immune system doesn’t recognize them.
Is antigenic shift a mutation?
Antigenic shift is contrasted with antigenic drift, which is the natural mutation over time of known strains of influenza (or other things, in a more general sense) which may lead to a loss of immunity, or in vaccine mismatch.
What is antigenic shift with example?
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 are antigenic drift and antigenic shift?
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 antigenic switching?
The altering of a microorganism’s surface antigens through genetic rearrangement, to elude detection by the Host’s immune system.
What is antigenic drift and antigenic shift quizlet?
antigenic drift. due to mutations. -minor change in amino acid composition in hemagglutinin or neuramindase. -results in decreased ability of the host cells to recognize them. -occurs among influenze A virus resulting in emergence of new variations of prevailing strains every year.
What is antigenic drift or genetic drift )? What is antigenic shift or genetic shift )? Quizlet?
Antigenic drift is the accumulation of random mutations in the RNA genome that can cause minor changes in hemagglutinin antigen structures. This occurs annually and is the reason we must have a seasonal flu shot.
What is the process of antigenic drift?
Antigenic drift is a natural process whereby mutations (mistakes) occur during replication in the genes encoding antigens that produce alterations in the way they appear to the immune system (antigenic changes) (Figure 1).
What is antigenic shift and antigenic drift in influenza?
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.
What is antigenic drift or genetic drift quizlet?
What is antigenic drift or genetic 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 antigenic shift and antigenic drift influenza?
Antigenic drift vs. shift. Antigenic drift creates influenza viruses with slightly modified antigens, while antigenic shift generates viruses with entirely new antigens (shown in red).
What feature of influenza virus leads to antigenic shift?
If the segment swapped encodes an influenza antigen (such as HA or NA) which is targeted by the host immune system, this is termed antigenic shift and can radically alter a host immune system’s ability to recognize the virus (Figure 3). Influenza A is responsible for most seasonal and pandemic flu outbreaks in humans.
Can antigenic shift happen in any virus?
Antigenic shift has been studied most extensively in influenza type A viruses, which experience this change about once every 10 years. The newly emerged viruses have the potential to cause epidemics or pandemics, since very few, if any, humans possess immunity against the new antigens.
Which type of mutation occur of 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.