Name of the virus of swine flu

Clades and subclades are shown on phylogenetic trees as groups of viruses that usually have similar genetic changes i. Dividing viruses into clades and subclades allows flu experts to track the proportion of viruses from different clades in circulation. Note that clades and sub-clades that are genetically different from others are not necessarily antigenically different. These proteins act as antigens. Antigens are molecular structures on the surface of viruses that are recognized by the immune system and can trigger an immune response such as antibody production.

Therefore, for antigenically different viruses, immunity developed against one of the viruses will not necessarily protect against the other virus as well. Influenza A H3N2 viruses also change both genetically and antigenically.

Influenza A H3N2 viruses have formed many separate, genetically different clades in recent years that continue to co-circulate. Similar to influenza A viruses, influenza B viruses can then be further classified into specific clades and sub-clades.

Influenza B viruses generally change more slowly in terms of their genetic and antigenic properties than influenza A viruses, especially influenza A H3N2 viruses. Influenza surveillance data from recent years shows co-circulation of influenza B viruses from both lineages in the United States and around the world. However, the proportion of influenza B viruses from each lineage that circulate can vary by geographic location and by season.

Figure 2 — This image shows how influenza viruses are named. The name starts with the virus type, followed by the place the virus was isolated, followed by the virus strain number often a sample identifier , the year isolated, and finally, the virus subtype.

CDC follows an internationally accepted naming convention for influenza viruses. The current flu season is on track to be one of the worst in a decade. According to the CDC, between million people have caught the flu since October and between 10,, people have died.

But as bad as the seasonal flu is this year, it pales in comparison to some of the biggest flu pandemics in history. However, even after the invention of the vaccine, pandemics still happen because flu viruses evolve very quickly. Here are five of the largest epidemics in recent history:.

Petersburg but it soon spread across Europe and the world. It was one of the first epidemics that was covered regularly by the developing daily press. Newspapers wrote about the local spread of the disease and also discussed the situation in other distant European cities thanks to telegraph reports. During the flu season, H1N1 caused the respiratory infection in humans that was commonly referred to as swine flu. In August , WHO declared the pandemic over. After the pandemic was over, the H1N1 flu virus became one of the strains that cause seasonal flu.

The flu vaccine can now help protect against the H1N1 flu swine flu. The H1N1 flu virus strain is included in the seasonal flu vaccine, including the vaccine for The signs and symptoms of flu caused by the H1N1 virus are similar to those of infections caused by other flu strains and can include:. It's not necessary to see a doctor if you're generally healthy and develop flu signs and symptoms, such as fever, cough and body aches.

Call your doctor, however, if you have flu symptoms and you're pregnant or you have a chronic disease, such as asthma, emphysema, diabetes or a heart condition, because you have a higher risk of flu complications. If you have emergency signs and symptoms of the flu, get medical care right away. For adults, emergency signs and symptoms can include:. Influenza viruses such as H1N1 infect the cells that line your nose, throat and lungs. The virus enters your body when you inhale contaminated droplets or transfer live virus from a contaminated surface to your eyes, nose or mouth.

If you live in or travel to an area where many people are infected with the H1N1 virus, you may be exposed to the virus. Each year's seasonal flu vaccine protects against the three or four influenza viruses that are expected to be the most common during that year's flu season.

The flu vaccine can reduce your risk of the flu and its severity and lower the risk of having serious illness from the flu and needing to stay in the hospital. Flu vaccination is especially important in the flu season because the flu and coronavirus disease COVID cause similar symptoms. Preventing the flu and reducing the severity of flu illness and hospitalizations could also lessen the number of people needing to stay in the hospital.

The flu vaccine is available as an injection and as a nasal spray. The nasal spray is approved for use in healthy people ages 2 through 49 years old. Minus Related Pages. On This Page. What is swine influenza? How many swine flu viruses are there? How does swine flu spread among pigs? What are signs of swine flu in pigs? How common is swine flu among pigs? Is there a vaccine for swine flu? Get Email Updates. To receive email updates about this page, enter your email address: Email Address.