What you need to know about a COVID-19 vaccine

Answers to the most common questions about coronavirus vaccine development.

UNICEF
What you need to know about a COVID-19 vaccine
UNICEF/UN0200242/Singh [NOTE: This is a file photo]
18 August 2021

Vaccines save millions of lives each year. The development of safe and effective COVID-19 vaccines is a huge step forward in our global effort to end the pandemic and to get back to doing more of the things we enjoy with the people we love.

We’ve gathered the latest expert information to answer some of the most common questions about COVID-19 vaccines. We will continue to update this article as more information becomes available.

How do COVID-19 vaccines work?

Vaccines work by mimicking an infectious agent – viruses, bacteria or other microorganisms that can cause a disease. This ‘teaches’ our immune system to rapidly and effectively respond against it. 

Traditionally, vaccines have done this by introducing a weakened form of an infectious agent that allows our immune system to build a memory of it. This way, our immune system can quickly recognize and fight it before it makes us ill. That’s how some of the COVID-19 vaccines have been designed.

Other COVID-19 vaccines have been developed using new approaches, which are called messenger RNA, or mRNA, vaccines. Instead of introducing antigens (a substance that causes your immune system to produce antibodies), mRNA vaccines give our body the genetic code it needs to allow our immune system to produce the antigen itself. mRNA vaccine technology has been studied for several decades. They contain no live virus and do not interfere with human DNA.

Are COVID-19 vaccines safe?

Yes, even though COVID-19 vaccines are being developed as rapidly as possible, they must go through rigorous testing in clinical trials to prove that they meet internationally agreed benchmarks for safety and effectiveness. Only if they meet these standards can a vaccine receive validation from WHO and national regulatory agencies.

UNICEF will only procure and supply COVID-19 vaccines that meet WHO’s established safety and efficacy criteria and that have received the required regulatory approval.

How were COVID-19 vaccines developed so quickly?

Scientists were able to develop safe effective vaccines in a relatively short amount of time due to a combination of factors that allowed them to scale up research and production without compromising safety: 

  • Because of the global pandemic, there was a larger sample size to study and tens of thousands of volunteers stepped forward 
  • Advancements in technology (like mRNA vaccines) that were years in the making 
  • Governments and other bodies came together to remove the obstacle of funding research and development 
  • Manufacturing of the vaccines occurred in parallel to the clinical trials to speed up production 

Though they were developed quickly, all COVID-19 vaccines approved for use by the WHO are safe and effective. 

Which COVID-19 vaccine is best for me?

All WHO-approved vaccines have been shown to be highly effective at protecting you against severe illness from COVID-19. The best vaccine to get is the one most readily available to you!

Will the COVID-19 vaccines work against the new variants?

WHO says that the vaccines approved to date are expected to provide at least some protection against new variants.

Experts around the world are continuously studying how the new variants affect the behaviour of the virus, including any potential impact on the effectiveness of COVID-19 vaccines.

Should any of the vaccines be shown to be less effective against one or more of these variants, it will be possible to change the composition of the vaccines to protect against them. In the future, changes to vaccinations such as the use of booster shots and other updates may be necessary.

But in the meantime, the important thing to do is to get vaccinated and continue measures to reduce the spread of the virus – which helps to reduce the chances for the virus to mutate – including physical distancing, mask wearing, good ventilation, regular handwashing and seeking care early if you have symptoms.

When shouldn’t you get a COVID-19 vaccine?

If you have any questions about whether you should receive a COVID-19 vaccine, speak to your doctor. At present, people with the following health conditions should not receive a COVID-19 vaccine to avoid any possible adverse effects:

  • If you have a history of severe allergic reactions to any ingredients of a COVID-19 vaccine.
  • If you are currently sick or experiencing symptoms of COVID-19 (although you can get vaccinated once you have recovered and your doctor has approved).

Should I get a vaccine if I’ve already had COVID-19?

Yes, you should get vaccinated even if you’ve previously had COVID-19. While people who recover from COVID-19 may develop some natural immunity to the virus, we do not yet know how long it lasts or how well you are protected. Vaccines offer more reliable protection.

Should I get the COVID-19 vaccine if I’m breastfeeding?

Researchers are currently studying COVID-19 vaccination in breastfeeding women, but there is still limited information at this time. WHO advises that vaccinations are offered if a lactating woman is part of a priority group for vaccinations, for example if you are a health worker. Breastfeeding can continue after vaccination and remains one of the best ways to protect your child from diseases and to help them stay healthy. 

Should I get the COVID-19 vaccine if I’m pregnant?

Although the overall risk of severe illness from COVID-19 remains low, pregnancy puts you at higher risk of severe illness compared to people who are not pregnant.

Research is still ongoing to understand the safety and effects of COVID-19 vaccination in pregnant women, but there is no known reason that would outweigh the benefits of vaccination for pregnant women. For this reason, pregnant women at higher risk of exposure to COVID-19 (e.g. health workers) or who have health issues that add to their risk of severe disease, may be vaccinated in consultation with their health care provider.

Can COVID-19 vaccines affect fertility?

No, you may have seen false claims on social media, but there is no evidence that any vaccine, including COVID-19 vaccines, can affect fertility in women or men. If you are currently trying to become pregnant, you do not need to avoid pregnancy after receiving a COVID-19 vaccine.

Can COVID-19 vaccines affect your DNA?

No, none of the COVID-19 vaccines affect or interact with your DNA in any way. Messenger RNA, or mRNA, vaccines teach the cells how to make a protein that triggers an immune response inside the body. This response produces antibodies which keep you protected against the virus. mRNA is different from DNA and only stays inside the cell for about 72 hours before degrading. However, it never enters the nucleus of the cell, where DNA is kept.

Do the COVID-19 vaccines contain any animal products in them?

No, none of the WHO-approved COVID-19 vaccines contain animal products.

How can I protect my family until we all receive a COVID-19 vaccine?

Safe and effective vaccines are a gamechanger, but it is still not clear the degree to which they can protect us against infection and transmission. For the time being, even once vaccinated we need to continue taking precautions to protect ourselves and others. This includes wearing masks, physical distancing and regular handwashing.

More information about the vaccination process in the Republic of Moldova can be found on the government website: www.vaccinare.gov.md.