Certification, boosters and travel
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Last updated: 19 May 2022
Thank you again for your participation which helps progress to be made in the development of effective COVID-19 vaccines.
The Government’s expert committee, the Joint Committee on Vaccines and Immunisations (JCVI), has advised all adults over 18 receive a booster dose of a COVID-19 vaccine, at least 3 months after their initial course of vaccination, to increase levels of protection.
This page provides important information and FAQs for vaccine study participants about boosters and on how they may obtain additional COVID-19 vaccines and a COVID Pass for international travel purposes, if needed.
The JCVI, together with chief investigators of the clinical trials, have considered the options in order to provide a clinical view on the risks, benefits, and the best approach to protect COVID-19 vaccine clinical trial participants.
We would ask that participants do not attend trial sites without an appointment unless they have an urgent concern. This is so that they can put arrangements in place, to support participants through this process. Study teams will write to participants, if they have not done so already, to explain the arrangements for their particular clinical trial.
In general, trial teams have written to participants who have received a vaccine that is not yet authorised by the Medicines and Healthcare products Regulatory Agency (MHRA), to offer them the option of receiving an additional vaccination course to facilitate travel. Please speak to your trial team for further information.
Scottish vaccine study participants can view full details on the Scottish NHS Inform website. Welsh vaccine study participants can view a written statement on the Welsh Government website. In Northern Ireland, letters have been issued to trial participants advising them to contact their trial team to discuss options.
Thank you for your patience as this is offered to all participants as early as possible.
Clinical trial participants (who are not on a booster trial) can be offered a booster.
You may be offered a study booster by your clinical trial team as part of the clinical trial you are participating in. If you are not offered a clinical trial booster, or would prefer to receive an approved booster, it is recommended you do so under guidance from your clinical trial team.
You should not take up a booster dose if you are on an active booster clinical trial, such as AstraZeneca Beta Variant or Sanofi booster, or if you have already had a booster dose on your clinical trial, unless your trial team contacts you to suggest this.
We recognise that some trial participants have been unable to take advantage of some of the benefits offered to people who have received a full course of approved vaccine, particularly overseas travel. This is because each country sets their own requirements for entry, and we are aware that many do not recognise trial vaccines.
The UK government has been working tirelessly with international partners including the G7, G20, EU Commission and the WHO to get recognition for trial participants. However, there is currently no internationally agreed policy or consensus on treatment of trial participants despite the UK government’s efforts.
We want to do everything we can for clinical trial participants. As a result, following consultation with the JCVI and in partnership with Chief Investigators of the trials, the UK government are making an offer to trial participants who wish to receive additional doses of approved vaccines, on top of the trial vaccines. This will make it easier for participants to travel overseas as they can prove they have been vaccinated with an MHRA authorised vaccine.
It is important to remember that you do not need a full course of additional vaccines at the moment for clinical reasons, this is for travel purposes only. There is still an expectation that the vaccines trialled in phase 3 studies in the UK will offer strong, long-lasting protection against COVID-19, even if they have not yet been approved.
Clinical trial participants are eligible to receive an additional course of vaccination for travel purposes once they have had a complete course of trial vaccines. If a study is still active, the participant will need to withdraw from their study in order to take up a full additional course for travel purposes.
An additional course of vaccine for travel purposes is only relevant for people taking part in trials in which the vaccine is not yet recognised in the country to which they plan to travel (please check before arranging an additional course of vaccine): Valneva, Medicago and some participants on ComCov2. Participants in other trials are unlikely to be eligible for an additional course of vaccine for travel purposes, as they would already have a vaccinated status recognised by overseas countries.
A fourth dose has now been approved in the UK for some people (those over 75 or with specific health conditions). Side effects of having additional vaccines after the initial two doses/ a full course of approved vaccine are generally mild and similar to initial vaccine doses, such as headache, pain at the injection site and mild fever.
While single booster doses have been approved for use after approved vaccines, more research is needed (and underway) to study the effects of a further additional dose.
Your trial doctor will be able to guide you through this before you have additional doses of vaccines, so that you can discuss the risks and benefits.
If you have had an active booster vaccine, the advice is that most people won't need another booster for now. However, if you have specific concerns, or are aged over 75 years or have specific health conditions, you should discuss the requirement with your trial team.
I had my booster as part of a trial more than 6 months ago. Can I get a further booster now to enable travel?
Most countries allow entry with evidence of full initial vaccination and only a few require evidence of a recent booster. We appreciate that some trial participants had their booster earlier than the rest of the population and that this may now be an issue for travel.
A fourth dose for travel purposes has not been approved at this time.
It is best to check entry requirements that are likely to apply for when you travel, as these are changing frequently. Alternative arrangements such as PCR testing are usually available as an alternative.
You will be invited for a discussion with a clinician on the clinical trial. They may offer you a booster as part of the trial, if this is built into the study you are participating in. Or they may advise on making an appointment for an approved booster at a vaccine centre linked with the clinical trial team.
If you were on a clinical trial of a vaccine that has since been approved by the MHRA (such as COV-001 or COV-002 AstraZeneca), you can access a booster from any vaccine centre when you are invited to do so, you do not need to speak to your clinical trial team first.
This will depend on whether you have been involved in a study in which the clinical trial vaccine used has been approved, or is yet to be approved.
If you have taken part in a trial of a vaccine now approved (Oxford AstraZeneca, Pfizer, Janssen, Moderna, Novavax or Valneva given in any combination) you can now accept an invite from the NHS and have a booster dose at any vaccine centre. If you are in a priority group, you will be invited to receive a booster or third dose of a COVID-19 vaccine in the national roll-out. You may need to take this letter along to the vaccine clinic to show to the vaccinator, before you receive your booster.
If you are involved in a study in which the clinical trial vaccine has not yet been approved (Medicago), boosters will be available from certain vaccination centres only, for the time being. Your clinical trial site will be in contact with you, as soon as they are ready to offer you an appointment, should you wish to have an additional vaccine. The process will take some time and we ask for you patience as this is rolled out across all sites. We would ask that participants do not call or attend clinical trial sites without an appointment unless they have an urgent concern. This is so that they can put arrangements in place, to support participants through this process. Thank you for your patience as this is offered to all participants as early as possible.
Please wait for your clinical trial site to contact you to offer you the opportunity to speak to a clinician about whether you would like to receive additional vaccines. If you do, they will discuss the risks and benefits with you, and whether you want to continue. If you do, they will help you make an appointment with a suitable vaccination site.
Arrangements are being made to link clinical trial sites with suitable vaccination sites nearby, which will usually be hospital sites. Your trial site will inform you on this in due course.
Please contact your study site, who will then be able to arrange a discussion with a trial clinician about having additional vaccine doses. We would be grateful if you could continue to be patient, as it will take time for all participants to be contacted and offered a discussion with a trial clinician.
I've tried to attend a vaccine centre for an additional vaccine, but they said I couldn't have one as I was on a trial. What should I do?
There are many vaccine sites operating across the country at the moment. However, only certain vaccination centres staffed by doctors who have been briefed about the clinical trials will be able to offer you the vaccine at this present time. This is usually hospital clinics who are linked with a clinical trial site. The reason for this is that they are able to offer an additional layer of safety, documentation and monitoring for participants. Vaccine sites are fully aware of the importance of supporting clinical trial participants.
If you were on a clinical trial of a vaccine that has since been approved (such as AstraZeneca), you can access a booster from any vaccine centre when you are invited to do so, you do not need to speak to your clinical trial team first. Please take this information with you to your appointment. It is however very important to inform your study doctor if you do receive another vaccine as this will be carefully recorded in the clinical trial record for your safety and for the study data.
Yes, having an approved booster (already and in future) would not stop you from having an additional top-up vaccine at a later date to support you to travel. For more information on this, read the FAQ below on “I had a booster/vaccine previously, how will it show on my NHS COVID Pass in future?”
You would need only one additional approved vaccine - so two doses of approved vaccine in total. You do not need a booster on top of a full additional course of vaccines at this time.
In line with the wider booster programme in England, three months will be required between the final dose of a course of active vaccination and a booster dose. If you are offered a booster as part of a clinical trial, there may be a shorter interval.
If you choose to have a top-up course, the relevant dose interval will be 8 weeks. This is the standard interval that the JCVI has recommended.
Your trial investigator will inform you of which vaccine you should receive. This will generally be the Pfizer vaccine except to those on mixed dose trials (such as Com-Cov). On some trials, you may be offered the option of receiving a trial booster.
Separate arrangements are being put in place for the devolved administrations.
Clinical trial participants (who are not on a booster study) can be offered a booster, in line with their priority group.
You should not take up a booster dose if you are on an active booster clinical trial, such as AstraZeneca Beta Variant or Sanofi booster, or if you have already had a booster dose on your trial, unless your trial team contacts you to suggest this.
You do not need a booster earlier than the rest of the population in your priority group.
Common side effects can be expected after additional doses, as with initial doses. These may include headache, arm pain and mild fever.
It is important to be aware that the need for, and safety of, additional boosters after clinical trial vaccines has not been fully evaluated and approved by the regulators in the normal way.
NHS COVID Pass
On 8 October, the government announced that clinical trial participants of relevant COVID-19 trials would be eligible to receive additional approved vaccine doses to facilitate travel abroad.
Clinical trial participants who have received additional doses of approved vaccines can now see those doses in their NHS COVID Pass for travel via the NHS App and online via NHS.UK where trial participants can download and print a PDF of their pass. These doses will show in the Travel Pass alongside trial vaccinations, with the vaccination received most recently appearing first.
Visit the NHS.uk NHS COVID Pass page for more information on how to access a digital NHS COVID Pass for travel.
Please note that vaccination records can take 1-5 working days to appear in the NHS COVID Pass.
It is not yet possible to use the NHS COVID Pass letter service to demonstrate a course of top up vaccines. However, if you have received a course of top up vaccines, you can download and print a PDF version of your NHS COVID Pass.
Using the domestic NHS COVID Pass in England
Some organisations and events have chosen to use the domestic NHS COVID Pass as a condition of entry. Anyone who took part in a clinical trial in England is able to use the NHS App or NHS.UK to obtain an NHS COVID Pass for domestic use in England.
You should contact your clinical trial site if you cannot yet access your domestic NHS COVID Pass.
How will the travel NHS COVID Pass show the additional course of vaccine? How long will it take for my additional vaccines to appear in my travel COVID Pass to allow me to travel?
For clinical trial participants who receive a top-up vaccine(s), their NHS COVID Pass will show their trial vaccines and their top-up vaccines. The top-up vaccines will appear in the NHS COVID Pass 1-5 days after each dose has been administered.
Many countries will only accept vaccinated travellers 14 days after the second dose has been administered; however, this time period can vary from country to country.
If you intend to travel internationally, you should confirm the entry requirements of your destination country using the Foreign, Commonwealth & Development Office travel advice website as requirements for vaccination can vary from country to country.
Booster doses are visible in the NHS COVID Pass and are labelled as booster doses. If you received a Pfizer booster vaccine and want it to contribute towards your travel top up, you can contact the Vaccine Data Resolution Service via 119 to have this dose coded as a primary course vaccine. This can only be done with Pfizer booster doses. Contact your clinical trial if you are unclear about the status of any of the vaccine doses you have received.
I’ve already had additional vaccines (without disclosing my trial vaccines). How does this affect me?
We do not recommend you receive additional vaccines until you have been invited to do so by your clinical trial site. Please inform your trial team at your next appointment, or earlier if you have any clinical concerns, that you have had additional vaccines as this is vital information for your safety and for the trial data.
Once I am able to receive additional doses, how long will it take before I am able to access an NHS COVID Pass for international travel?
It will take at least 8 weeks for trial participants to receive the two additional doses. The second dose of the additional vaccine will be available in the NHS COVID Pass 1-5 days after you have received the second dose.
Many countries will only accept vaccinated travellers 14 days after the second dose has been administered; however, this time period can vary from country to country. Anyone intending to travel internationally should confirm the entry requirements of their destination country using the Foreign, Commonwealth & Development Office travel advice website as requirements for vaccination can vary from country to country.
Frequently asked questions
Yes, we encourage everyone to take up the offer of a flu vaccine as soon as it is offered to you.
We are sorry that some participants have had difficulties with foreign travel plans and in some cases, have had to incur additional costs for PCR tests for example. However, we have no control over the entry requirements set by other countries. The NHS does not cover tests for people wishing to travel abroad.
In certain circumstances, for a small number of studies, you may be able to reclaim certain additional costs for PCR tests for travel from the trial organiser. Please check with your clinical trial site. The UK Government is taking steps to make sure that vaccine trial participants have equal status domestically to people who have had a deployed vaccine. They are also working with international organisations and other countries on their entry criteria.
Approved COVID-19 vaccines
The Pfizer/BioNTech, Oxford/AstraZeneca and Moderna vaccines are now being rolled out across the UK.
These developments are a tribute to the global efforts of the life sciences industry, researchers and volunteers, underlining the importance of this vaccine research. It is thanks to you and all those involved, that we have this encouraging news about vaccines.
It is important that clinical trials into a number of other COVID-19 vaccines continue. Different vaccines work in different ways and we still need to collect important information about which vaccines work best, and are best for different groups of people, and on exactly how effective they are at, for example, preventing severe infection, preventing infection as a whole, preventing transmission etc. We also need information on matters such as the best way to use vaccines, the number of doses, and to check long term that there are no safety concerns.
Keep taking part
It is really important that people keep taking part in all the COVID-19 studies, attend their follow-up appointments and submit data on their health and COVID-19 infections. We need volunteers to join new studies and existing studies are not yet complete, and we need the long term data to help us understand how best to use the vaccines, which are most effective and to give information on the levels of effectiveness, as well as reassurance on long term safety of them.
Here are some answers to questions you might have about what these developments mean for the clinical study you are taking part in.
Thank you for your continued interest in COVID-19 vaccine research.
Yes, the trials will continue because we need data about a number of different vaccines and their safety and effectiveness, in order to protect the population.
We need several vaccines to ensure an adequate supply and because some vaccines may be easier to transport and store than others. We need further data on whether one or other vaccines are better suited to specific groups of people, such as older people or people with other medical conditions, and all the trials are giving information on safety, which is so important to gather.
Thank you for your participation - it is thanks to people taking part in trials that we now have approved vaccines.
It’s a personal choice but we believe it is. All the studies now recruiting will give you an active vaccine during the trial. Taking part in a study is the best way to help effective vaccines to be identified and made available to everyone earlier, and may even give you early access to a vaccine later found to be effective.