How Long Does it Take for the Flu Shot to Work?

The human body carries out his function in a set of metabolic processes. Unlike the automatic and digital world, we live in now, where everything just happens with a click. Our body requires quite a while to go through the processes of making sure things happen. For one’s immunity to be at the optimal level, the lifestyle one lives has to be healthy. Proper rest after a day’s work, eating a good, healthy and balanced diet, exercising regularly, all helps the body to function correctly and gives the immune system the necessary boost. When one falls sick or gets infected, the immune system fights back to protect the body from the attack. In some cases, it does this by eradicating the problem swiftly and instantly. In other cases, the body requires a little time to recognize the antigen of the foreign body before fighting back. These processes may take some time but once done, like a computer, the nature and makeup of the invader have now been saved to memory. The next time the body encounters that particular disease, there is an already prepared and mobilized defense line ready to destroy it. So, for the body to generate the appropriate immunity against the influenza virus after the administration of the vaccination, it takes roughly 10 to 14 days. Some people may feel a little discomfort during the first to two days of receiving the flu shots, but this is very subtle as it is most likely the body reacting to the newly introduced vaccine, or flu shot.

How Does the Flu Shot Work?

The flu shot carries out its protective function by stimulating the typical immune response by the body. The twist is that there is no harm or danger the shot itself poses to the body but due to scientific manipulations, the body still identifies the shot as a threat and builds a defense against it. Usually, when this is happening, the virus is meant to be causing havoc and weakening the body, since the vaccines only have enough of the virus to be recognized by the immune complex and elicit a response, the body is safe from being ridden with the disease. Therefore, after the introduction or injection of the Influenza shot, the body develops antibodies to combat the flu virus. Antibodies are specialized proteins that are present in our blood created to fight off an infection that threatens the integrity of our health. Once, the flu virus enters the system, the already produced antibody springs into action to destroy it and they wait for the next invasion to fight again. Although one’s immunity wanes over time, there is nothing to worry about as one can take the shots annually. The other reason for the yearly injection is because the virus changes every year, this modification has to be studied, and new ways developed to annihilate the mutated virus.

How long does Flu Shot Pain Last?

The pain of a needle entering one’s body can be unbearable. I remembered how terrified of injections I was as a child. I still prefer taking pills compared to receiving jabs anywhere. Despite being a Doctor, these fear of the pain from the needle stays with me, I can try to bear it like a man, but if there is another option available, I will gladly take it instead. When one receives the flu shot, one feels the pain of being jabbed, but this will subside. The pain that now appears for an extra day or two is merely that of the body making antibodies against the influenza strain. Which is a good sign that the vaccination is working? So, now that the pain felt from the vaccination have been distinguished, the length of the pain from flu shot lasts for about a day or two, depending on the individual.

If I Get a Flu Shot am I Contagious?

The answer is No. Receiving the flu shot does not make an individual contagious as there are no viruses in the vials, if there are any present, they are already killed and inactivated. Since it is only a live virus that can reproduce and cause infection, there is no such threat as infecting other people with the Flu. The only way this may seem possible is if one gets infected with the real influenza virus within the two weeks window period that the body uses to develop immunity. At that point what makes one contagious is not the vaccine but the contracted illness that has nothing to do with the flu shot at all.

Are There Different Types of Flu Shots?

Yes. There are two types of flu shots, namely the trivalent and the quadrivalent. The trivalent vaccines offer protection against three flu viruses, two influenza A viruses and one influenza B virus, while the quadrivalent shots protect the body against four influenza viruses, two each for influenza A and B viruses. The trivalent vaccines contain the A/Michigan/45/2015 (H1N1) pdm09-like virus, an A/Hong Kong/4801/2014 (H3N2)-like virus and a B/Brisbane/60/2008-like (B/Victoria lineage) virus. While the quadrivalent shots have the three mentioned with the addition of the fourth one, a B/Phuket/3073/2013-like (B/Yamagata lineage) virus. This 2017-2018 season the nasal spray flu shot (LAIV – Life Attenuated Influenza Vaccine), was not recommended, only injectable flu shots are approved for use. There are standard doses shots that can be given either intramuscularly or intradermally. There are high dose vaccines that are adequate for older ones, and they can also be given shots with adjuvants. There are shots made from viruses cultivated in cell culture while there recombinant vaccines that are not made up of viruses at all; they are manufactured using a vaccine production technology.

Protection against the Influenza during this season is an essential thing to do. The benefits are vital, as one ends up protecting other people staying close as well. If there are any worries, one could get the help of a healthcare professional, or one could do some research. But, one should not have any deterrent in taking the shots, just once for the season and the immune system is battle ready.




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