Covid-19 Booster Vaccine Factsheet

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For information on the Covid-19 vaccines available in the UK, please refer to our previous blog post which details what they are, how they work, and who can take them.

As we approach winter in the UK, the government has recommended that certain people receive booster doses of approved vaccines in order to maintain high levels of immunity to Covid-19. This fact sheet will tell you everything you need to know about these vaccine boosters.

Why do we need booster vaccine doses?

At the time of writing, the NHS vaccination programme in the UK has successfully delivered 95 million doses, with over two thirds of the population receiving two doses. This has enabled generally high degrees of immunity, and drastically reduced the proportion of people with the virus being admitted to hospital, or developing life-threatening symptoms.

Some vaccines provide long-term immunity (such as the one-dose BCG vaccine providing protection against childhood tuberculosis) but evidence suggests that the high level of protection from the Covid-19 vaccines fade over time, which means that booster shots are required to ‘top up’ the body’s immunity to the disease.

This is similar to how flu vaccines work, where booster doses are recommended to be given once a year. 


To be clear, COVID-19 is not the flu, and is a much more serious condition that is far more life-threatening.


Who is eligible for a booster vaccine dose?

At the moment, the NHS is recommending that only the most vulnerable people receive booster doses of COVID-19 vaccines. You are in this group if you received your 2nd dose of the vaccine over six months ago AND:

  • You are aged 50 and over, or
  • You live or work in care homes, or
  • You are a frontline health and social care worker, or
  • You are aged 16 and over with a health condition that puts you at high risk of getting seriously ill from COVID-19, or
  • You are aged 16 and over who are a main carer for someone at high risk from COVID-19, or
  • You are aged 16 and over and live with someone who is more likely to get infections (such as someone who has HIV, has had a transplant or is having certain treatments for cancer, lupus or rheumatoid arthritis)

Pregnancy and the Covid-19 booster vaccine dose

If you are pregnant and in one of the above groups, you can also receive a booster dose. Vaccination rates have been lower among pregnant women, resulting in higher rates of serious COVID-19 in this group. 

If you’re pregnant and meet any of the above criteria, be sure to get your booster, or first / second vaccine dose.


Why the sudden rush for booster vaccine doses?

With winter approaching, the country is facing a health crisis on multiple fronts. The Covid-19 pandemic is not over: at the time of writing in October 2021, there are 47,000 new cases per day in the UK and the NHS receiving over 1,000 hospital patients per day with the virus. 

According to the government, if infections continue on their current trajectory the country could see up to 100,000 new Covid-19 infections per day. The dominant variant of the virus in the UK (the Delta Variant) spreads much more easily than the strain of coronavirus that caused the first wave in the spring of 2020.

In addition to Covid-19, other viruses that cause pressure on the NHS, and life-threatening illness, are expected to resurge during the winter. Both the flu and norovirus thrive in winter conditions, and the population’s immunity to the flu may have been negatively impacted due to the extreme reduction in flu infections last winter, which were down by 95%.

With restrictions on our movement and gatherings lifted, both viruses will have the opportunity to spread, and it’s vital that vulnerable people are protected. 

Please note, that the flu vaccine is also important for vulnerable groups, and it’s recommended that certain people are vaccinated against both diseases. If you’re eligible for the Covid-19 booster vaccine dose, you’re probably also eligible for a flu vaccine, or booster vaccine dose. Find out more about the flu vaccine here.

Vaccinating against both COVID-19 and the flu at the same time is both safe, and effective.


What’s in the COVID-19 booster vaccine doses?

The UK has approved four COVID-19 vaccines, three of which have been used already in the current vaccination programme:

  • Moderna vaccine
  • Oxford/AstraZeneca vaccine
  • Pfizer/BioNTech vaccine
  • Janssen vaccine (available later this year)

Booster doses of the Moderna, AstraZeneca, and Pfizer vaccines are exactly the same as the first and second doses. The Moderna and Pfizer are MRNA vaccines, and the AstraZeneca is a more traditional form of vaccination that uses a weakened version of the common cold. For information about what’s inside each vaccine, and how they work, read our fact sheet on vaccinating against COVID-19.

All approved COVID-19 vaccines in the UK have been thoroughly tested and are safe to use. Misinformation about the vaccines is common across social media, always be sure to rely on trusted sources when seeking advice about COVID-19.

What type of vaccine booster will I get?

The vaccine booster dose you receive may be different to the vaccine you were given for your first or second dose. 

For instance, if you received two doses of the AstraZeneca vaccine earlier this year, you may be offered a dose of the Pfizer/BioNTech vaccine as your booster. This might seem strange, but offering a booster that is different to the first two doses is safe. 

Where can I get my booster vaccine dose?

The NHS should contact you when you’re eligible for the booster dose, much like the first two doses. You will then be invited to book an appointment

Booster vaccine doses will be delivered from one of the many vaccination centres, pharmacies, or doctor’s surgeries across the UK. You can probably book an appointment at the same place you received your first two doses.

If you believe you’re eligible, but haven’t been contacted, you can book your booster dose with the NHS using this online form


What if I haven’t been vaccinated yet?

Only those who have already been fully vaccinated will be invited to receive booster doses. 

If you haven’t been vaccinated yet and you’re aged 12 or over, then it’s vital that you get your first and second doses in order to protect yourself from Covid-19. 

Racialised (ethnic minority) people are more likely to experience life threatening illness from the virus, and the Delta variant is highly transmissible. It’s the best way to protect you, and those around you from serious infection.

Booking your vaccine is quick and easy. You can book your first or second vaccination dose using the NHS online form here. Or you can use this online tool to find your nearest walk-in vaccination centre.