What is the third COVID-19 vaccine dose?

20 December 2021

Are you taking an immunosuppressant for your Crohn’s or Colitis? If so, you may be eligible for a third dose of the COVID-19 vaccine.

We are aware that there are some delays and problems in people getting their third vaccine dose. We are working hard to make your voices heard. We are working with the government and healthcare providers to make sure that eligible people are identified and invited to receive their third dose as soon as possible. We will update our information as more guidance follows.

The Joint Committee on Vaccinations and Immunisation (JCVI) has recommended that people aged 12 years and over who were immunosuppressed (have a weakened immune system) at the time of their first and second COVID vaccines (primary vaccination) should receive a third dose of COVID-19 vaccine. The JCVI is an independent committee that advises the government on vaccination schedules and vaccine safety.


What is the third vaccine dose for people who have a weakened immune system? 

This vaccination is being called a ‘third dose’ as it is being recommended as part of your primary COVID-19 vaccination. The first two doses of the vaccine also make up your primary vaccination. This third dose is only being offered to people who are less likely to have had a strong immune response to the first two doses. 

I haven’t had my third vaccine dose yet 

If you have had two vaccines and are eligible for your third vaccine dose, see our coronavirus vaccine page for information on how to book your vaccine

It is important that whoever is offering you a vaccine (whether that is your GP, hospital or vaccination centre) knows you are eligible for a third dose. This is because if you are offered the Moderna vaccine you should be given a full dose instead of the half dose that is given as the booster. So you need to tell the vaccination centre before they give you the injection.  

It may help to show your specialist, GP or the vaccination centre this letter to explain your situation.

Do I need the booster if I've had a third dose? 

If you have this third dose, you will be eligible for a booster (which will be your fourth dose) from three months after your third dose.  

How do I get a booster dose (fourth dose) after I have this third dose? 

You will be eligible for a booster dose from 3 months (91 days) after your 3rd dose.

In England, you cannot book your booster online. If it has been three months since your third dose and you have a letter from your GP or hospital specialist inviting you for a third dose, you can attend any walk-in site offering boosters to get your booster. You must take your letter with you. Read more on the NHS website about who can use a walk-in site.

In Northern Ireland, if it has been three months since your third dose you can book your booster online.

In Scotland and Wales, you will be invited for your booster by your GP, Specialist or health board when it's due.

How do I get a booster (fourth dose) if my third dose was recorded as a booster?  

We know that some people couldn’t get a third vaccine dose or didn’t know they were eligible, so they had a booster when they were invited. You might be worried that you missed out on a dose or received the wrong vaccine. The Pfizer booster is a full dose which is the same for both the third vaccine and the booster. If you had the Moderna booster, you would have been given a half dose rather than the full dose which is recommended for people who have a weakened immune system. The half dose should still provide a good immune response in most people but you should also get the booster (fourth dose) when offered to boost your protection. 

We are working hard to make sure that everyone who was eligible for a third vaccine dose will have their records updated so they are invited for their booster (fourth dose). We have asked the NHS and governments how they are going to make sure that everyone who was eligible for the third dose will get their booster (fourth) dose. At this stage, we haven't had a response. We will update this page when we find out more. 

Why is a third dose needed and who will get it?

Some people who are immunosuppressed because of an underlying health condition or the medicines they are taking, may not have responded as well to their primary vaccines as those who are not immunosuppressed. This includes people with Crohn’s and Colitis who are taking certain doses of immunosuppressant treatment.

It is not possible to know who will or will not have responded, so the JCVI is recommending that all people with certain conditions or taking certain medicines should receive the third dose. This is different from a ‘booster’ dose which may be needed as initial response to the vaccine reduces.

If you were taking one of these medicines for your Crohn’s or Colitis around the time of your first or second dose of vaccine you will be eligible for this third dose. This may depend on the dose that you were taking and when you took the medication in relation to your first or second doses of vaccine.

What medication were you taking? What dose were you taking? When were you taking the medication?
Adalimumab (Amgevita, Humira, Hyrimoz, Idacio, Imraldi) Any dosage In the 3 months before your first or second dose of vaccine
Infliximab (Flixabi, Inflectra, Remsima, Remicade, Zessly) Any dosage In the 3 months before your first or second dose of vaccine
Golimumab (Simponi) Any dosage In the 3 months before your first or second dose of vaccine
Ustekinumab (Stelara) Any dosage In the 3 months before your first or second dose of vaccine
Tofacitinib (Xeljanz) Any dosage In the 3 months before your first or second dose of vaccine

High dose corticosteroids (for example prednisolone)

Equivalent to 20mg or more prednisolone per day for more than 10 days

In the 3 months before your first or second dose of vaccine

Moderate dose corticosteroids (for example prednisolone)

Equivalent to 10mg or more prednisolone per day for more than 4 weeks

In the 3 months before your first or second dose of vaccine

Methotrexate

More than 20mg per week

In the 3 months before your first or second dose of vaccine

Azathioprine (High dosage that is unlikely to include people with Crohn’s or Colitis)

More than 3mg/day per 1kg of body weight. For example, if you weighed 60kg, this means you would be taking a dose of 180mg/day. 

In the 3 months before your first or second dose of vaccine

Mercaptopurine (High dosage that is unlikely to include people with Crohn’s or Colitis)

More than 1.5mg/day per 1kg of body weight. For example, if you weighed 60kg, this means you would be taking a dose of 90mg/day. 

In the 3 months before your first or second dose of vaccine

Prednisolone plus another immunosuppressant

7.5mg per day

In the 3 months before your first or second dose of vaccine

If you started taking any of the above medicines at least two weeks after your second vaccine dose a third dose is not recommended at this stage.

If you have another condition as well as Crohn’s or Colitis, this may also affect whether you will be offered a third dose. See the JCVI’s advice for further information about other conditions and medication that may mean you are eligible for the third vaccine dose. Contact your healthcare team if you are unsure whether you are eligible.

What if I'm taking a different dose of immunosuppressant or vedolizumab?

At this stage, only the people specified in the table above are eligible to receive their third vaccine dose according to the JCVI. However, the British Society of Gastroenterology (BSG) recommend that all people with Crohn’s or Colitis who are on any immunosuppressive treatment receive a third or booster dose of vaccine. This would include people taking vedolizumab or lower doses of azathioprine or mercaptopurine. Read the BSG position statement here. We will update our information as more guidance follows.

What vaccine will I receive?

If you are aged 18 and over it is likely that you will get the Pfizer or Moderna (full dose) vaccine. The AstraZeneca vaccine may be given to people who have previously had this vaccine if there is a supply issue with the Pfizer or Moderna vaccine.

Is it OK to mix vaccines?

If you are eligible for a third dose, you may be offered a different vaccine to your first two vaccine doses. In particular, people who previously received the AstraZeneca vaccine are now likely to receive the Pfizer or Moderna vaccine as their third dose, as recommended by the JCVI.  

Recent studies suggest that having the AstraZeneca vaccine followed by the Pfizer vaccine gives a better immune response than two AstraZeneca vaccines, although these studies did not include people who were immunosuppressed.

How and when will I get my third dose?

Specialist teams are responsible for identifying the people who need a third dose. If you have Crohn's or Colitis your specialist team will be your IBD team.

Once you have been identified as eligible you should be contacted with information on how and when to have your third dose vaccine. For most people this will mean having your third dose at your hospital's vaccine centre. But for some people they may be invited to have it at their GP surgery (for example if their hospital is too far away to get to).

If you have received a letter that you are eligible for the third dose, you can book your appointment on the NHS website

Your third dose should be given at least eight weeks after your second dose. This is just the minimum gap. It is still recommended you have your third dose even if it has been much longer than eight weeks since your second dose.

Both the JCVI and the British Society of Gastroenterology (BSG) recommend that, if possible, you should have your vaccine when your immune system is at its strongest. This is recommended because the vaccine may be less effective once you are more immunosuppressed. However, NHS England has also pointed out that for some people who are on 'regular, long term immunosuppressive therapy, or where the degree of immunosuppression is relatively constant' that timing your dose around your injections or infusions is likely to be less important. 

If you are currently going through a treatment cycle or about to move to a different or higher dose medication that would make you more immunosuppressed, your IBD team may advise on specific timings for your third dose. However, currently there is no national guidance on this. 

There are some times when you might need to delay either your vaccine or medicine. These are:

  • If you feel very unwell on the day of your appointment (for example if you have a high fever or symptoms of coronavirus), your vaccine may be postponed until you have fully recovered.
  • If you're scheduled to have the shingles vaccine. You should ideally wait 7 days between the coronavirus vaccine and the shingles vaccination as it is a live vaccine and may react with the COVID-19 vaccine. This does not apply to other vaccines, such as the flu jab.
  • If you're taking steroids. Your IBD Team may recommend that you've tapered down to a lower dose, or have finished your course of steroids, before you have the COVID-19 vaccine. This is because the vaccine will be more effective if you are not taking a higher dose of steroids. However, it is still safe to take the vaccine while on steroids.
  • If you're already taking a biologic or immunosuppressant medicine, or just about to start a new biologic or immunosuppressant.  Speak to your IBD team about the best time to have your vaccine doses. The vaccine may be less effective once you start a biologic or immunosuppressant. However, it is still safe to take the vaccine while on these medicines

You can find more information about your risk level and what you can do to lower your risk of getting COVID-19 here.

To read more on the coronavirus vaccine for people with Crohn’s or Colitis see our information here

It’s great news that some people with Crohn’s and Colitis on immunosuppressants will be invited for a third dose of the COVID-19 vaccine. A huge thank you to the clinicians, researchers, and the people living with Crohn’s and Colitis who took part in research that helped with this decision. It’s vital this research continues and gets investment.

The third dose could offer extra protection for those who may have had a weakened immune response after two doses. But, this time around, we need to make sure that every eligible person is identified, contacted and booked in.

Sarah Sleet
Chief Executive