Mass vaccination programs have been launched around the world to control the Covid-19. As of August 28, 2021, 5.13 billion doses have been given globally, and 36.21 million doses are given each day. So, 33% of the world population got at least one dose of the Covid-19 coronavirus vaccine. It is often heard that many people are suffering from coronavirus even after taking two doses of the vaccine. However, it was hoped that the risk of Covid-19 would be greatly reduced after vaccination. Therefore, a new question was raised, how long the Covid-19 vaccine protection will last? Though there has not been any specific answer to this question, and research is still going to find that.
But we often see new variants of coronavirus being invented in different countries. Some of these variants spread the infection at a deadly rate, and the severity of the disease is also high. The recent outbreak of the delta variant is a prime example of this. The delta variant is now available in more than 130 countries. Countries around the world are worried about the increasing number of infections and deaths due to the new Covid-19 variants. In this situation, the question arises again, how effective are the current Covid-19 vaccines against the newer variants?
Usually, vaccines give us complete protection, but the reality about the Covid-19 vaccine is, it can't provide complete protection, and Covid-19 can attack the vaccinated person too. But there may be some relief from the risk of too much damage.
How long does the Covid-19 Vaccine take to Build Immunity?
After vaccination, the human body takes some time to recognize the genetic components of the coronavirus and to make antibodies and T-cells. These then begin to block the virus from entering the body's cells or kill the infected cells. So, it takes at least two weeks or more for the vaccine to become fully effective.
How does the Covid-19 Vaccine Work in the Human Body?
The COVID-19 vaccine usually works on developing Immunity to the virus that causes COVID-19 without making us sick. Several types of vaccines work on providing protection in several ways, but commonly the vaccines provide the body with "memory" T-lymphocytes and B-lymphocytes that will recall how to fight the virus in the future.
It normally takes a few weeks for the vaccinated body to make T-lymphocytes and B-lymphocytes after vaccination. Thus, a person may become infected with the Covid-19 virus just before or immediately after vaccination and later become ill because there was not enough time for the vaccine to fight against the virus.
After the vaccination, the immunity building process can raise symptoms such as fever. These symptoms are normal, and it is a sign of increased Immunity of the body.
Types of Covid-19 Vaccines
Currently, there are four main types of COVID-19 vaccines, mRNA vaccines, whole virus vaccines, protein subunit vaccines, and viral vector Covid-19 vaccines.
mRNA vaccines are normally genetically engineered mRNA that provide instructions to your cells to make S protein available on the Covid-19 virus' surface. After our cells replicate the protein, they destroy the genetic material from the vaccine. Our body understands that the protein should not be there and should make T-lymphocytes and B-lymphocytes, which can make the vaccine to fight the virus in the future. Pfizer-BioNTech and Moderna are examples of mRNA vaccines.
The whole virus vaccine includes Sinopharm and Sinovac, which work on weakening or deactivating the form of the pathogen that is responsible for the Covid-19. These types of vaccines use inactivated pathogens. So, they cannot replicate or infect the cells but can work on triggering the immune response. Therefore, a booster dose might be needed for complete safety.
The protein subunit vaccine has purified pathogen instead of the whole pathogen to trigger the immune response. Once vaccinated, our immune system realizes that proteins are not included in the body and begins to produce T-lymphocytes and antibodies. If we ever become infected in the future, memory cells will recognize and fight the virus. Novavax is an example of a protein subunit vaccine.
Viral vector Covid-19 vaccines put a new and modified version of the virus known as "the vector," which ultimately delivers genetic code for antigen. Once the viral vector enters into our cells, the genetic material instructs the cells to make a protein that causes the virus-19. Using these instructions, our cells replicate the protein.
Further, it induces our bodies to produce T-lymphocytes and B-lymphocytes, which will remind the body how to fight the virus if we become infected in the future. Oxford-AstraZeneca and Sputnik V are examples of viral vector vaccines.
Coronaviru Vaccine Efficiency
As you already know, several types of vaccines have been given to prevent coronavirus. However, how long the Immunity of any corona vaccine will last is still unclear.
According to a recent report, a new study by the Centers for Disease Control and Prevention, the first dose of Pfizer-BioNTech and modern vaccines is 80 percent effective, and the second dose is 90 percent effective. People who have been vaccinated have a lower risk of corona than others.
People who have taken Pfizer-BioNTech vaccines will have Immunity for at least 6 months. It is 100% effective for CDC-listed sick people and 95.3% for FDA-listed patients. The Pfizer-BioNTech vaccine is also known to be effective in South Africa. Also, the Oxford-AstraZeneca vaccine has an efficacy of up to 90 percent when given two doses.
Side Effects of COVID-19 Vaccines
Like all other medicines or vaccines, Covid-19 vaccines have some side effects. But, in most cases, the side effects are very mild, such as pain at the injection site, swelling, redness, weakness, muscle and joint pain, nausea, fever, fatigue, etc. However, no serious side effects have been reported so far. But, if there is any problem after the vaccination, you must go to the nearest hospital and seek doctor's advice.