Is type A or B flu more common?

Influenza A is the most common, followed by influenza B. Both are highly contagious, and their symptoms are similar. Influenza, also known as the flu, is a viral respiratory illness that is most prevalent during fall and winter months.

What is the difference between influenza A and influenza B?

Influenza B almost exclusively infects humans and is less common than influenza A. Flu type B also mutates about two to three times more slowly than influenza A. Because humans are the natural host of influenza B, pandemics generally do not occur with influenza B viruses.

What is the incidence and prevalence of influenza?

While the impact of flu varies, it places a substantial burden on the health of people in the United States each year. CDC estimates that influenza has resulted in between 9 million – 45 million illnesses, between 140,000 – 810,000 hospitalizations and between 12,000 – 61,000 deaths annually since 2010.

Can you get influenza A twice?

It is possible to get the flu twice during the same flu season. Since there are two types of flu strains – influenza A and influenza B – if you get influenza A, you can also get influenza B.

How long is flu B contagious?

When Flu Spreads Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. Children and some people with weakened immune systems may pass the virus for longer than 7 days.

How long does the flu B last?

For most healthy people, the flu is an uncomfortable but short-term illness that resolves itself as the immune system fights it off. Symptoms usually appear from one to four days after exposure to the virus, and they last five to seven days.

What is the incidence rate of flu?

The flu has resulted in 9.3 million to 49 million illnesses each year in the United States since 2010. Each year, on average, five to 20 percent of the United States population gets the flu. It is estimated that the flu results in 31.4 million outpatient visits and more than 200,000 hospitalizations each year.

What is the incidence rate of influenza?

Results. The statistical estimate of influenza incidence among all ages ranged from 3.0%–11.3% among seasons, with median values of 8.3% (95% confidence interval [CI], 7.3%–9.7%) for all ages, 9.3% (95% CI, 8.2%–11.1%) for children <18 years, and 8.9% (95% CI, 8.2%–9.9%) for adults 18–64 years.

How are influenza A and B viruses related?

More Information about Flu Viruses. Influenza A and B viruses are responsible for seasonal flu epidemics each year. Influenza viruses can change in two different ways—antigenic drift and antigenic shift. Influenza A viruses also are found in many different animals, including ducks, chickens, pigs, whales, horses and seals.

Which is worse the flu a or B?

For a person who is generally healthy, the flu is not typically dangerous. However, it can severely affect certain groups of people, who should seek medical attention as soon as they suspect that they have flu symptoms. Many people believe that influenza A is more severe than influenza B. However, this is not always the case.

What are types of flu?

There are four types of influenza viruses: A, B, C and D. Human influenza A and B viruses cause seasonal epidemics of disease almost every winter in the United States. The emergence of a new and very different influenza A virus to infect people can cause an influenza pandemic.

When is the flu most common in the United States?

It’s most common during the fall and winter months. It typically spreads through respiratory droplets when a person who has the flu sneezes or coughs. The family of viruses that influenza is a part of is large. You may have heard that there are different types of influenza viruses — particularly influenza A and influenza B.