How long does the flu vaccine work? Will you get the flu after the flu shot?

The flu vaccine is an influenza virus inactivated vaccine that produces antibodies in the human body after vaccination, thereby exerting a protective effect. So, how long does the flu vaccine work? How long is the flu vaccine valid? Also, will you get the flu after the flu shot?

How long does the flu vaccine work? Will you get the flu after the flu shot?

 How long does the flu vaccine work?

It usually takes about 15 days after the flu vaccine to produce effective protective antibodies. Therefore, it is recommended to start vaccination about one month before the peak of influenza epidemic in order to play a more effective role in vaccine protection. It is generally appropriate to get a flu shot from September to November before the annual influenza epidemic, and a 60%-90% protection effect can be obtained.

Of course, the specific onset time, individuals may have differences. Vaccines rely on the immune system of an individual to produce an immune response, so if the immune system is different, it may affect the concentration and duration of antibodies produced.

In addition, just because there is a 15-day onset time, it also means that after the flu vaccine, you may still get flu or general flu. Therefore, if the flu vaccine is feverish after the fight, but the body temperature is too high, it may be coupled with other diseases, be vigilant. Therefore, after the flu vaccine, pay attention to keep warm and avoid colds.



How does the vaccine produce antibodies?

After the vaccine enters the body, it is engulfed by phagocytic cells, and the phagocytic cells present antigen to the T cells, and then the T cells are presented to the B cells, thereby causing the B cells to divide and differentiate into plasma cells and memory cells, and the plasma cells produce antibodies, and when the same antigens are again At the time of invasion, the memory cells rapidly divide and differentiate to produce plasma cells, and the plasma cells produce antibodies.

How long is the flu vaccine valid?

Influenza virus antibodies can only last for about a year. People who need a flu shot need to be revaccinated every year because the epidemic strain of the flu virus may change every year. The vaccine will be developed for the current strains. Even if the circulating strains that are going to be popular in the new season have not changed, it is very necessary to get a flu shot every year. Fight every year to continue to gain immunity.

The antibodies produced by the flu vaccine will not disappear.

Note that the requirement must be a dozen per year, not the antibody produced in the previous year has disappeared (actually it will not disappear for almost a lifetime). But the flu virus mutates very quickly, and new viruses come out every year. If you don't hit it, you won't be immune. So the flu vaccine is new every year. Must be produced before the flu season.

Will you get the flu after the flu shot?

The flu virus mutates very quickly. Every year, new viruses come out and they are played every year. If you don't fight, you will not have immunity. So the flu vaccine is new every year. Must be produced before the flu season. However, what is popular for next year is actually guessing (of course not purely broken guess), that is to say, there is the possibility of guessing wrong. Therefore, if you have a flu shot, it does not mean you will not get the flu.

In order to reduce this possibility, influenza vaccines generally contain three different viruses. The current influenza vaccine is an influenza virus inactivated vaccine composed of three viruses.

In addition, even if you guessed it, if the virus mutates before the end of the season, or if you happen to be infected, it may still be shot. If there is any such thing as swine flu avian flu, it is even more difficult to predict.