The truth is, no one really knows. Flu strains are mutating all of the time. Each time a flu strain mutates to act in a different way, it is given another name (if we actually discover it and can recognize that it is different). The other problem is discovery. Often, different strains act in the same way. Therefore, it isn't really important to distinguish between strains. Only strains that seem to 1) be popular in the next flu season or 2) pose a great threat to humans are actually identified.
The influenza virus doesn't always cause recurrent infections. There are many different strains of the flu and there are two types, which are Type A ad Type B. The flu is a virus that has to run its course.
There are many strains of flu virus, & they are constantly mutating; you can only become immune to strains of flu that your body has already encountered, or that you have been immunized against.
The flu virus constantly mutates, leading to new strains every year. Vaccine manufacturers update the vaccine annually to include the most prevalent strains, providing the best protection. This process helps ensure that the vaccine is effective against the specific flu viruses circulating each year.
Influenza is a viral disease that encompasses many different strains of the influenza virus. Each strain can cause flu-like symptoms, and they are constantly changing and evolving, necessitating yearly flu vaccines to protect against the most prevalent strains.
Swine flu H1N1 is considered an antigenic shift, as it resulted from a reassortment of genetic material from different influenza virus strains in animals. This led to the emergence of a new subtype that can infect humans.
Typically the flu vaccine is trivalent, with three strains.
Because there are many strains of flu virus, so unless you have immunity to them all you will catch flu again.
The influenza virus doesn't always cause recurrent infections. There are many different strains of the flu and there are two types, which are Type A ad Type B. The flu is a virus that has to run its course.
The flu, warts and mumps are all caused by different viruses. The flu is caused by any of the influenza viruses, warts are caused by certain strains of human papillomavirus, and mumps are caused by the mumps virus.
There are many strains of flu virus, & they are constantly mutating; you can only become immune to strains of flu that your body has already encountered, or that you have been immunized against.
There is currently only one strain of influenza virus that causes pandemic Swine Flu. It is called A-H1N1/09. There have been previous strains of H1N1 that were similar, and some were even called Swine Flu, but they were different than that which causes the Swine Flu of the 2009 pandemic. See related questions below.
The flu virus constantly mutates, leading to new strains every year. Vaccine manufacturers update the vaccine annually to include the most prevalent strains, providing the best protection. This process helps ensure that the vaccine is effective against the specific flu viruses circulating each year.
Influenza is an RNA virus. Being that it is an RNA virus it has a high rate of mutation that goes unchecked. This high rate of mutation leads to different strains of the influenza virus
Yes, it is possible to still get the flu even if you received the flu shot, as the vaccine may not provide complete protection against all strains of the virus.
No, if you have it you will be immune to it after that. However, viruses are able to mutate to slightly different strains rapidly. If that happens and you are exposed, you may still have some immunity, but you may not, in which case you could get the flu from a similar but different form of the virus.
A flu shot will prevent the type of influenza virus or viruses that have been used to make the vaccine. A,nd it may sometimes protect against a different, but very similar, strain.
A flu vaccination is only good for the season because the flu virus changes over time. Without getting into the technical details of how it works, a virus can adapt and change over time by gaining new genetic traits, making it a completely different 'virus' that causes the same disease, but is genetically different than the one before it. Because of this, a vaccination of the old flu virus will not last for life. An old flu vaccination will protect against the original, but the new strand is basically 'unknown' to your body and will cause infection.