There is a lot of discussion right now about the side effects of the Covid-19 vaccine and confusion surrounding the taking of the vaccine. However, if we dissect these discussions, we will find that the logical conclusion is to take the vaccine in order to protect yourselves and others during the pandemic.

Risk of blood clots

This is one of the most widely debated side effects of Covid-19 vaccines. Let us use an example to understand the risks. The Johnson and Johnson Covid-19 vaccines have been given to about seven million people in the United States, but the vaccine has been temporarily paused due to possible blood clots in six vaccine recipients. It is normal to have such a temporary pause. In the meantime, the US Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) will examine if blood clotting has anything to do with the vaccination. Doctors will also be informed during this time on how to treat such side effects if they potentially occur in other persons. It is expected that the FDA will soon lift the pause and reintroduce the vaccine to the public.

But most importantly, if someone becomes seriously ill after being infected with the coronavirus, their chances of blood clots are many, many times higher. It is safe to say that the cases of vaccines causing blood clots are extremely rare and even if that occurs, it is thought that about 85 percent of cases can be cured through treatment. Any widely used drug (such as paracetamol or antacids) is not 100 percent risk free. Vaccines have some side effects too, which is normal and acceptable. Covid-19 is killing 10,000 to 12,000 people every day around the world. Now, think how extremely rare the chances are, if there are any, of blood clots forming from Covid-19 vaccination versus how many people are dying from Covid-19 each day. No doubt, the benefits of the approved Covid-19 vaccines far outweigh the risks, and that is why the European Medicines Agency and WHO are constantly advocating that people take the vaccine. 

Can vaccinated people get infected, and why is the second dose so critical?

People are also worried about the fact that a minority of vaccinated individuals are still being infected with the coronavirus even after taking the Covid-19 vaccine. This is because taking the first dose of a two-dose vaccine develops only partial immunity, so do not neglect to take the second dose of the vaccine. Because the immune system is not completely functional with the first dose of the vaccine, it is important to follow perfectly the protective measures even after the first dose. Immunity will be complete within two to three weeks of the second dose of vaccine. Therefore, the second dose cannot be omitted in any way.

Can people who have fully completed the vaccine dose become infected with the coronavirus? The answer is that it is very unlikely, because if the coronavirus enters the body, the immune system will be activated very quickly in those vaccinated individuals and will kill the virus and keep us free from the disease.

However, new variants of the coronavirus are being found around the globe, which is also a normal process. If the vaccine is made using the old variant of coronavirus, the effectiveness of the vaccine against the new variant of the virus might be reduced, so a small number of people who have been vaccinated (with both doses complete) may still be infected with the new variant of coronavirus. But the most important thing is that even if someone who has been vaccinated becomes positive for coronavirus, the person will develop mild to moderate symptoms as the vaccine will give protection. As a result, that person is highly unlikely to require hospitalisation.

Why safe and effective Covid-19 vaccine should be taken

In sum, the possibility of blood clots as a result of the vaccine is extremely low. Even if a person is infected with a new variant of the coronavirus after receiving the vaccine, he or she will develop mild to moderate but not severe versions of the disease because vaccine-induced immunity will give protection, and he or she will not need to be hospitalised. There is no more effective way to eradicate viral diseases than vaccines. For example, smallpox has been eradicated from the world and polio has been eradicated from Bangladesh—both were made possible due to vaccines. Vaccines are one of the most invaluable gifts of science and we should not squander this opportunity.

Dr Rezaul Karim is an immunologist, Drug Discovery and Regulatory Affairs in the Netherlands.