Experts answer frequently asked questions on Covid-19 vaccine

Does vaccination completely prevent infection?

According to the Centres for Disease Control (CDC), one can still get infected after you’ve been vaccinated. But chances of getting severely ill or getting hospitalised are minimal

Many people think vaccines work as a shield, blocking a virus from infecting cells altogether. But in most cases, a person who gets vaccinated is protected from disease, not necessarily infection. Vaccination does not prevent you from getting infected 100 per cent but gives the immune system a huge leg up on the coronavirus. Whatever the outcome, one becomes better off after encountering the virus than if you hadn’t been vaccinated.

How long does protection from Covid-19 last?

Dr Patrick Amoth, director-general of, Ministry of Health, says it is too early to give a clear answer on the percentage of protection. What is available is that Covid-19 has caused very serious illness and death. If you get Covid-19, you also risk passing it to loved ones who may get very sick. Getting a Covid-19 vaccine is a safer choice.

Experts are working to learn more about both natural immunity and vaccine-induced immunity. The World Health Organisation (WHO) will release data on the same. Efficacy data from phase III clinical trials of each of the vaccines being released. Later, a follow-up to evaluate the effectiveness of the different vaccines over time will be done.

Can we trust vaccines that have been developed so fast? Is it safe to be one of the first people to be vaccinated?

“I was the 001 patient in Kenya, just to inspire that confidence of healthcare workers and all Kenyans. I know the benefit of getting any vaccination,” says Dr Amoth.

Vaccine acts as a source of protection and by extension, shields one’s family and the people one interacts with. For a vaccine to be registered and administered, it has undergone robust and rigorous testing for safety, efficacy and quality.

According to WHO, because the vaccines have been developed in record time thanks to important technological advances and experience gained does not imply that the process was not rigorous and that the usual steps were not followed.

Clinical trials have three phases: the first one consists of confirming the safety of the drug, a fundamental aspect that is also confirmed in phases II and III of the trial, which involves the participation of thousands of people. Therefore, all vaccines approved by the regulatory agencies are safe. This means that when vaccination campaigns begin, tens of thousands of people have already received the vaccine during clinical trials.

If I have had the virus and recovered, do I still need to be vaccinated?

Whether you have been infected or not, one needs to be vaccinated to offer protection from further infection because the experts are still not sure how long you are protected from getting sick again after recovering from Covid-19. According to the CDC, if one was treated for Covid-19 with monoclonal antibodies or convalescent plasma, they should wait 90 days before getting a Covid-19 vaccine.

If I have been vaccinated, can I still spread the virus?

The clinical trials were designed to evaluate whether the vaccines prevented Covid-19 symptoms, not whether they prevented viral infection. Therefore, there is no clear answer to this question yet. However, the fact that the vaccines considerably cut symptomatic infections suggests that they will also reduce viral transmission since it has been shown that asymptomatic people are less contagious than those with symptoms.

Reducing infection is not the same as blocking infection. So vaccinated individuals must continue complying with safety protocols — use of facemasks and social distancing, among others until a large percentage of the population has been vaccinated.