Coronavirus (COVID-19)

Vaccination safety

Anyone who gets COVID-19 can become seriously ill or have long-term effects ('long COVID'). The COVID-19 vaccines are the best way to protect yourself and others.

For information on how to get vaccinated, go to getting a 1st, 2nd or booster jab.

Why COVID-19 vaccines are important

Research has shown the vaccines:

  • significantly reduce your risk of getting seriously ill or dying from COVID-19
  • reduce your risk of getting symptoms of COVID-19
  • will help reduce your risk of catching and spreading COVID-19

You need 2 doses for stronger, longer-lasting protection. The 1st dose should give you good protection from 3 or 4 weeks after you've had it.

There is a chance you might still get or spread COVID-19 even if you have a vaccine, so it's important to continue following the government's social distancing guidance.

The NHS video below explains what's in the COVID-19 vaccines and how they work.

COVID-19 vaccines safety and side effects

The COVID-19 vaccines approved for use in the UK have met strict standards of safety, quality and effectiveness.

Organisations in the UK that have approved the vaccine include the Medicines and Healthcare products Regulatory Agency (MHRA), the Commission on Human Medicines, the Joint Committee on Vaccination and Immunisation and the National Institute for Biological Standards and Control. Public Health England is monitoring vaccine effectiveness through ongoing analysis and enhanced surveillance.

A Public Health England study of more than 1 million people in at-risk groups, published in July 2021, found COVID-19 vaccines used in the UK are as effective at preventing symptoms in most people with underlying health conditions as they are for the rest of the population.

Development of the COVID-19 vaccines was based on many years of extensive research on virus vaccines. International co-operation has meant clinical trials were carried out simultaneously around the world, and included people of Black/African, Hispanic/Latino and Asian heritage.

The vaccines can cause some side effects, but not everyone gets them.

Any side effects are usually mild and should not last longer than a week. Examples are:

  • a sore arm from the injection
  • feeling tired
  • a headache
  • feeling achy
  • feeling or being sick

Side effects can be reported through the MHRA Yellow Card Reporting Scheme. For summaries of reports made through the scheme, go to GOV.UK: weekly summary of Yellow Card reporting.

More serious side effects are very rare.

For more information on side effects, go to NHS: COVID-19 vaccines safety and side effects

COVID-19 vaccination for children aged 12 to 15 years-old

The medicines regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), has confirmed the Pfizer-BioNTech vaccine is safe and effective for 12 to 17 year-olds. This followed a rigorous review of the safety, quality and effectiveness of the vaccines in this age group.

The UK has also benefited from having data from the US, Canada and Israel, which have already offered vaccines universally to young people aged 12 to 15 years-old.

For more information, go to GOV.UK: vaccination programme for children and young people.

COVID-19 vaccination for children aged 5 to 11 years-old

Children will be offered the Pfizer-BioNTech COVID-19 vaccine. Each vaccine is a third of the dose of vaccine that is given to older children and adults.

Children at greater risk of serious illness if they catch COVID-19 will need 2 doses of vaccine, 8 weeks apart. All other children will be offered 2 doses of vaccine 12 weeks apart.

For more information, go to GOV.UK: a guide for parents of children aged 5 to 11 years-old.

COVID-19 vaccine ingredients

The COVID-19 vaccines do not contain egg or animal products.

The Oxford-AstraZeneca vaccine contains a tiny amount of alcohol, but this is less than in some everyday foods like bread.

The vaccines are suitable for people of all faiths.

Pregnancy and breastfeeding

You can have a COVID-19 vaccine if:

  • you're pregnant or think you might be
  • you're breastfeeding
  • you're trying for a baby

The vaccine cannot give you or your baby COVID-19.

The antibodies you develop in response to the vaccine will be shared with your baby, offering your baby protection from birth.

You'll be invited to have the vaccine when it's offered to your age group, or earlier if you have a health condition or any other reason that means you're eligible.

If you're breastfeeding, you can have any of the COVID-19 vaccines.

The vaccine is not passed to your baby through breast milk, but antibodies made by your body will be.

If you're pregnant and have not had a vaccine yet, it's best for you to have the Pfizer-BioNTech or Moderna vaccine. This is because they've been used more widely during pregnancy in other countries and no safety concerns have been found. More than 90,000 pregnant women have received these vaccines safely.

If you've already had the Oxford-AstraZeneca vaccine for your 1st dose and did not have any serious side effects, you should have it again for your second dose.

To arrange your vaccination, go to NHS: book your COVID-19 vaccination. If you're under 40, you'll only be shown appointments for the Pfizer-BioNTech or Moderna vaccine. If you're 40 or over, you'll be asked if you're pregnant so you'll only be shown appointments for these vaccines.

At your appointment, you'll be able to discuss the benefits and potential risks of having a COVID-19 vaccine in pregnancy. This is so you can make an informed decision about having it. You can also speak to a GP or your maternity team for advice.

Find out more at GOV.UK: vaccine advice if you're pregnant, may get pregnant or are breastfeeding.


There's no evidence that COVID-19 vaccines have any effect on your chances of becoming pregnant. There is no need to avoid pregnancy after vaccination.

There's no evidence that vaccines for COVID-19 have any effect on sperm count. Research has shown that coronavirus (COVID-19) can affect sperm count and erectile function, however, similar to the effect of other viruses such as mumps and Zika.

For more information, go to Royal College of Obstetricians and Gynaecologists (RCOG) and Royal College of Midwives: vaccines, fertility and pregnancy.

Further information

The NHS will offer the COVID-19 vaccine for free to everyone in the UK, starting with people most at risk from coronavirus. For information on the NHS COVID-19 vaccine programme, go to:

The following respected independent medical and fact-checking organisations provide up-to-date information on the vaccine, its use and effects: