Table of Contents
- 1 What increases the possibility of antigenic shift in influenza virus?
- 2 What is the most effective way to prevent influenza?
- 3 Does antigenic shift caused pandemic?
- 4 How many deaths and hospitalizations occur each year in the US due to influenza infections?
- 5 What is the flu virus made of?
- 6 What is the main problem in the use of the influenza vaccine?
What increases the possibility of antigenic shift in influenza virus?
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 the most effective way to prevent influenza quizlet?
The best way to prevent influenza is with annual influenza vaccination.
What is the most effective way to prevent influenza?
CDC recommends a yearly flu vaccine as the first and most important step in protecting against flu viruses. Flu vaccines help to reduce the burden of flu illnesses, hospitalizations and deaths on the health care system each year. (Read more about flu vaccine benefits.)
Why is it difficult to develop a vaccine for the flu?
Viruses are small and simple. Influenza A has just 11 proteins, and just a few of them are accessible on the surface of the virus, where the immune system can “see” them. Influenza can change the appearance of these surface proteins easily and quickly.
Does antigenic shift caused pandemic?
Antigenic shift results in a new influenza A subtype that is so different from previous subtypes in humans that most people do not have immunity to the new virus. An antigenic shift can lead to a worldwide pandemic if the virus is efficiently transmitted from person to person.
Which is more likely to happen antigenic drift or antigenic shift?
Antigenic shift: Much less frequent than antigenic drift (occurring only in influenza A), it involves a profound change in the virus with a new hemagglutinin or neuraminidase type produced, possibly from another species; for example, simultaneous infection of a host with a human and avian influenza strain can result in …
How many deaths and hospitalizations occur each year in the US due to influenza infections?
* 2019 to 2020 season is a preliminary estimate.
| Season | Hospitalizations | Deaths |
|---|---|---|
| Estimate | 95\% UI | |
| 2016-2017 | 500,000 | (29,000 – 61,000) |
| 2017-2018 | 710,000 | (37,000 – 95,500) |
| 2018-2019 | 380,000 | (19,000 – 97,000) |
In which way is the influenza virus most likely?
Most experts believe that flu viruses spread mainly by tiny droplets made when people with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby.
What is the flu virus made of?
All influenza viruses consist of single-stranded RNA as opposed to dual-stranded DNA. The RNA genes of influenza viruses are made up of chains of nucleotides that are bonded together and coded by the letters A, C, G and U, which stand for adenine, cytosine, guanine, and uracil, respectively.
Is it possible to catch influenza twice?
Yes, because the virus can mutate (change). If you become infected with the swine flu virus, your body produces antibodies against it, which will recognize and fight off the virus if the body ever meets it again.
What is the main problem in the use of the influenza vaccine?
But the difficulty with influenza vaccines is that the yield of human influenza viruses on tissue culture is much lower than in embryonated eggs. A new high-yield donor is needed for construction of recombinants with a new pandemic strain, which can replicate in a stable cell line with high titre.
How long did it take for a influenza vaccine?
It takes approximately five to six months for the first supplies of approved vaccine to become available once a new strain of influenza virus with pandemic potential is identified and isolated.