What are Influenza Type A Flu and Type B Flu?


What are Influenza Type A Flu and Type B Flu?


When it comes to the flu, not all types are created equal. You’ve probably heard that there are a few different types of the flu. According to the CDC, there are three types of influenza viruses: influenza A, influenza B and influenza C. Influenza A and B are the two main types that routinely spread in humans and cause seasonal flu epidemics. Influenza C viruses cause only mild respiratory infections and are not thought to be responsible for epidemics. 

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Influenza A vs B: Brief History & Transmission

Influenza A viruses are the most harmful, as they can cause severe disease. Wild aquatic birds are often the hosts for a large variety of influenza A viruses. Sometimes these viruses are transmitted from bird to human and can cause devastating outbreaks. Some of the subtypes of influenza A that have caused the largest number of known human deaths are:14, 15

  • H1N1, which caused Spanish Flu in 1918 and Swine Flu in 2009


  • H2N2, which caused Asian Flu in 1957


  • H3N2, which caused Hong Kong Flu in 1968


  • H5N1, which caused Bird Flu in 2004


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.


Although scientists can classify and monitor the different types of flu viruses, it is virtually impossible for them to develop effective vaccines that provide lifelong immunity. The reason: Flu viruses mutate (change their genetic structure) and replicate (produce new, identical copies of themselves) extremely quickly, making it difficult for scientists to keep up.


Signs of Influenza A or Influenza B Symptoms

The good news is most people will recover from the flu on their own. However, if you have a severe case of the flu, you should see your healthcare provider. Not sure if you have the flu? A good indication of whether or not you have the flu is if a  href="https://vicks.com/en-us"
 indicates you have a fever.

Influenza A and Influenza B Treatment

While over-the-counter medications cannot cure the flu, they can help ease your symptoms while you wait for it to run its course. If you’re suffering from a sore throat, headache, cough, fever, runny nose, or minor aches and pains,  href="https://vicks.com/en-us/shop-products/nyquil/cold-flu-relief-liquid-medicine"
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>NyQuil Cold & Flu
 and  href="https://vicks.com/en-us/shop-products/dayquil/cold-flu-liquid-medicine"
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>DayQuil Cold & Flu
 are both good options since they contain a pain reliever/fever reducer and cough suppressant. If you’re suffering from more symptoms, try  href="https://vicks.com/en-us/shop-products/nyquil/nyquil-severe-cold-flu-liquid"
data-action-detail="NyQuil SEVERE Cold & Flu"
>NyQuil SEVERE Cold & Flu
, which also contains a decongestant, and  href="https://vicks.com/en-us/shop-products/dayquil/dayquil-severe-cold-flu-liquid"
data-action-detail="DayQuilSEVERE Cold & Flu"
>DayQuilSEVERE Cold & Flu
, which has an expectorant to help loosen congestion in your chest. Soon enough, you’ll be on the road to recovery.

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