COVID-19: Vaccines

Information on COVID-19 vaccines in the UK and vaccination programmes worldwide COVID-19: Vaccines

Overview

COVID-19 vaccines are being developed worldwide. All must be assessed as effective and meet strict safety standards before being used. In the UK, the Medicines and Healthcare products Regulatory Agency (MHRA), an independent authority, assess the safety, quality, and effectiveness of medicines.

UK Government guidance on the UK groups that must be prioritised for COVID-19 vaccine can be found here: Priority groups for coronavirus (COVID-19) vaccination: advice from the Joint Committee on Vaccination and Immunisation (JCVI). The second phase of the UK immunisation programme is an age-based approach starting with the oldest adults first [1]. The NHS will contact individuals to let them know when it is their turn to have the vaccine. Further information on the UK vaccine programme is available on the NHS website.

International travellers have not been identified as a priority group for COVID-19 vaccination, but would be eligible for the vaccine if in priority groups. NaTHNaC is closely monitoring recommendations and will provide travel related updates as relevant.

Vaccines available in the UK

Most vaccines being developed use the spike (S)-protein on the virus surface as the target for antibodies that develop when the vaccine is administered to block the virus entering the cells and therefore expected to be protective against COVID-19 infection.

The following vaccines have been approved for use in the UK:

Pfizer BioNTech COVID-19 vaccine

This vaccine is a nucleoside- modified messenger RNA vaccine (mRNA). The genetic code (mRNA) from the SARS-CoV2 virus is used in the vaccine to enter cells of the person vaccinated to make the target S-protein stimulating the antibody response blocking viral entry into cells.

AstraZeneca COVID-19 vaccine

This vaccine uses a virus that does not cause illness, called a chimpanzee adenovirus (ChAD) to carry the genetic sequence of the SARS-COV S-protein into the cell of the person vaccinated to stimulate the antibody against the S-protein of the virus.

COVID-19 Vaccine Moderna

This vaccine is a nucleoside- modified messenger RNA vaccine (mRNA). The genetic code (mRNA) from the SARS-CoV2 virus is used in the vaccine to enter cells of the person vaccinated to make the target S-protein stimulating the antibody response blocking viral entry into cells.

COVID-19 Vaccine Janssen

This vaccine is made up of virus (from the adenovirus family) that has been modified to include DNA that codes for the S-protein on the SARS-CoV-2 virus. The vaccine stimulates an antibody response thereby blocking viral entry in to cells.

The vaccines are MHRA authorised and considered inactivated (including the non-replicating adenovirus vaccine) [1-3].

Vaccine Schedule Age Duration of protection
Pfizer BioNTech COVID-19 vaccine (mRNA vaccine)

Two intramuscular doses of 0.3mls at a minimum interval of 21 days*

16 years and older** Booster doses are not recommended until further vaccine trial studies have been completed
AstraZeneca COVID-19 vaccine
(ChAD)
Two intramuscular doses of 0.5mls at a minimum interval of eight weeks* An interval of 28 days may be used when rapid protection is required e.g., prior to starting immunosuppressant treatment Adults aged 18 years and older (see important footnote)*** Booster doses are not recommended until further vaccine trial studies have been completed
COVID-19 Vaccine Moderna Two intramuscular doses of 0.5mls at a minimum interval of 28 days* Adults aged 18 years and older**


Duration of protection is unknown at present
Janssen COVID-19 Vaccine  Single intramuscular dose of 0.5 mL  Adults aged 18 years and older****  To be confirmed****
Note these vaccines are supplied in multidose vials

* It is recommended that the second dose of all vaccines should be routinely scheduled around 8 weeks after the first dose for individuals in the first 9 priority groups who have not yet received both doses in order to ensure those most vulnerable have the strongest possible protection against the virus at an earlier opportunity. It may also be recommended that the interval between the two doses be shortened to less than 12 weeks in periods of high or increased disease incidence [4].

** Vaccination with the Pfizer vaccine may be considered for children from 12 years of age with severe neuro-disabilities who tend to get recurrent respiratory tract infections and who frequently spend time in specialised residential care settings. If the Pfizer vaccine is not available, Moderna vaccine may be used "off-license" for this age group [1]. On the 4 June 2021 the Medicines and Healthcare products Regulatory Agency (MHRA) authorised an extension to the UK approval allowing the use of Pfizer BioNTech vaccine in 12 to 15 year olds. Further Joint Committee of Vaccination and Immunisation (JCVI) guidance on the use of this vaccine in this age group is awaited.

*** Based on current evidence the UK, JCVI advises that, in addition to those aged under 30, unvaccinated adults aged 30 to 39 years who are not in a clinical priority group at higher risk of severe COVID-19 disease, should be preferentially offered an alternative to the AstraZeneca COVID-19 vaccine, where possible, and only where no substantial delay or barrier in access to vaccination would arise.

For those aged 18 to 29 years the precautionary advice for a vaccine preference is stronger, reflecting a gradient in the benefit-risk balance with age.

This new advice is specific to the current UK context and should there be a deterioration in any of the above factors, JCVI advises that vaccination of adults aged 30 to 39 years with any of the UK-authorised vaccines is always better than no vaccination, except where there are specific contraindications [1,5].

**** Further details will be added when available in Immunisation against infectious disease Chapter 14a.

The second dose of vaccine should preferably be administered using the same vaccine used for the first dose. If the same vaccine is not available, it is considered reasonable to give the vaccine available particularly if at immediate high risk of COVID-19 infection or considered unlikely to attend for vaccination again [1]. There are certain other situations such in which may be appropriate to give a different vaccine to the first, providing there are no contraindications. More information is available in COVID-19 vaccination programme: information for Healthcare Practitioners [4].

Whilst it is strongly advised that the second dose is given at the recommended interval, an inadvertent or unavoidable delay beyond the interval is unlikely to adversely affect the response to the second dose and longer-term protection. There is no need to restart the course and the second dose should be given as soon as can be arranged (preferably using the same vaccine to complete the course). Timely administration is still encouraged to significantly boost protection and prevent further hospitalisations and deaths [4].

Based on current information about these COVID-19 vaccines, there should ideally be an interval of at least seven days with other vaccines to avoid incorrect attribution of potential adverse events [1]. As the current COVID-19 vaccines in the UK are considered inactivated, where individuals in an eligible cohort present having received another inactivated or live vaccine, COVID-19 vaccination should still be considered. The same applies for other live and inactivated vaccines where COVID-19 vaccination has been received first or where a patient presents requiring two vaccines. In such circumstances, patients should be informed about the likely timing of potential adverse events relating to each vaccine [1].

More information about the use of COVID-19 vaccines for those with special health needs including during pregnancy, breastfeeding and those who are immunosuppressed or have HIV infection is available in Immunisation against infectious disease Chapter 14a.

Contraindications and precautions to COVID-19 vaccination

There are very few individuals who cannot receive the Pfizer-BioNTech, AstraZeneca or Moderna COVID-19 vaccines. Information on the Janssen vaccine to be updated.

Contraindications:

Confirmed previous systemic allergic reaction (including immediate-onset anaphylaxis) to

  • a previous dose of the same COVID-19 vaccine [see also Adverse Reactions]
  • any components of the vaccine e.g. polyethylene glycol

The MHRA no longer advises that individuals with a history of anaphylaxis to food, an identified drug or vaccine do not get the vaccine, as long as they are not known to be allergic to any component (excipient) of the vaccine [1]. Polyethylene glycol (PEG) is present in the Pfizer-BioNTech and Moderna vaccines [1]. Known allergy to PEG (present in some medicines, household goods and cosmetics) is rare but if known, the individual should not receive the Pfizer-BioNTech or Moderna vaccines. Some individuals are allergic to polysorbate 80 widely used in medicines, foods and some medicines including some injected influenza vaccines. Individuals with known allergy to polysorbate 80 should not receive the AstraZeneca vaccine.

The British Society for Allergy and Clinical Immunology (BSACI) has advised that individuals who have a reaction to the first dose of a COVID-19 vaccine may be able to receive a 2nd dose. For further details see flow chart for managing patients who have allergic reactions to the first dose.

The MHRA has also undertaken a review into UK reports of very rare blood clots together with low levels of platelets (thrombocytopenia) following vaccination with the COVID-19 vaccine AstraZeneca. The following are considered contraindications for receiving the AstraZeneca COVID vaccine:

  • cerebral or other major blood clots occurring with low levels of platelets after their first vaccine dose of the AstraZeneca COVID-19 vaccine
  • a history of rare immune-mediated syndromes characterised by a thrombosis with low platelet levels (thrombocytopenia), this includes those who have previously had heparin induced thrombocytopenia or the same specific clinical picture in association with anti-phospholipid syndrome [6]. These individuals may be offered an alternative COVID-19 vaccine [6].

A history of thrombosis without low platelet levels is not a contraindication to AstraZeneca COVID vaccine [6].

COVID-19 vaccine guidance is subject to regular revisions, check up to date information on COVID-19 and blood clotting on GOV.UK.

Precautions:

If acutely unwell, postpone until fully recovered.

Vaccination of individuals who may be infected or asymptomatic or incubating COVID-19 infection is unlikely to have a detrimental effect on the illness.

Vaccination should be deferred in those with confirmed infection to avoid confusing the differential diagnosis. As clinical deterioration can occur up to two weeks after infection, ideally vaccination should be deferred until clinical recovery to around four weeks after onset of symptoms or four weeks from the first confirmed positive specimen in those who are asymptomatic.

No safety concerns have been noted from vaccinating those with past COVID-19 infection or detectable COVID-19 antibodies.

Having prolonged COVID-19 symptoms is not a contraindication to receiving COVID-19 vaccine, but if the individual is seriously debilitated, still under active investigation, or there is evidence of recent deterioration, deferral of vaccination may be considered to avoid incorrect attribution of any change in the person’s underlying condition to the vaccine [1].

In the UK, the JCVI currently advises that, in addition to those aged under 30, unvaccinated adults aged 30 to 39 years who are not in a clinical priority group at higher risk of severe COVID-19 disease, should be preferentially offered an alternative to the AstraZeneca COVID-19 vaccine, where possible and only where no substantial delay or barrier in access to vaccination would arise.

For those aged 18 to 29 years the precautionary advice for a vaccine preference is stronger, reflecting a gradient in the benefit-risk balance with age.

This new advice is specific to the current UK context and should there be a deterioration in any of the above factors, JCVI advises that vaccination of adults aged 30 to 39 years with any of the UK-authorised vaccines is always better than no vaccination, except where there are specific contraindications [5]. See guidance for healthcare professionals for further detail.

Adverse reactions

Local reactions at the injection site are common and other symptoms including fever, muscle and joint aches, fatigue and headache are reported with these vaccines. Detailed information about adverse reactions following COVID-19 vaccination is available in Immunisation against infectious disease Chapter 14a.

Following COVID-19 vaccination, a mild fever, which usually resolves within 48 hours, is a common, expected reaction and isolation is not required unless COVID-19 is suspected.

As with all medicines and vaccines in the UK, the MHRA monitor COVID vaccines on an ongoing basis to ensure their benefits continue to outweigh any risks. The MHRA has undertaken a thorough review into UK reports of a very rare and unlikely to occur specific type of blood clot in the brain, known as cerebral venous sinus thrombosis (CVST) occurring together with low levels of platelets (thrombocytopenia) following vaccination with the COVID-19 vaccine AstraZeneca. It is also considering other blood clotting cases (thromboembolic events) alongside low platelet levels. The MHRA publish regular reviews and recommendations on the use of the vaccines.

As the COVID-19 vaccines are labelled with a black triangle, all adverse reactions occurring in individuals of any age after vaccination should be reported to the MHRA using the Yellow Card Scheme. A summary of the reports are published on the GOV.UK website.

Travel: vaccine and proof of vaccination

Currently the World Health Organization (WHO) does not recommend proof of vaccination or immunity for international travel as a condition of entry to a country until there is more scientific knowledge and equitable distribution COVID-19 vaccine globally [7]. There is no recommendation under International Health Regulations to use the International Certificate of Vaccination or Prophylaxis for proof of COVID-19 vaccination.

Rather than a condition of entry, some countries have indicated that entry requirements will be eased for travellers if proof of COVID-19 vaccination or COVID-19 immunity can be shown. Each country should indicate what would be accepted as proof of vaccination or immunity. It is likely that COVID-19 testing will still be required by each country regardless of vaccination status.

England

From 17 May 2021, international travellers from England who have received two COVID-19 vaccines can access their COVID-19 vaccination status through a NHS App [8]. Those travellers who do not have access to a smartphone and know that their planned destination requires COVID-19 vaccination status, can call the NHS helpline on 119 (from 17 May 2021) and ask for a letter to be posted to their home address.

Those aged 13 to 15 who have been vaccinated, will need to contact their GP surgery to request access to GP online services before being able to use the app.

Wales

Those who urgently need to travel to a country which requires vaccine certification, and who are not able to either quarantine or provide tests to meet country entry requirements can request a vaccination certificate for essential international travel by calling 03003035667.

Information on a digital option for international travellers for Welsh Citizens will be available shortly.

Scotland

If COVID-19 vaccination was received in Scotland, a printed copy of vaccination status can be accessed from NHS Scotland online [sign in required] or by phoning the COVID-19 Status Helpline 0808 196 8565.

Northern Ireland

Options for proof of vaccination given in Northern Ireland are under development. Updates will be available shortly.

The Foreign, Commonwealth & Development Office (FCDO) details the current entry requirements of each country including information about self-isolation and necessary COVID-19 testing.

Whilst abroad and irrespective of the number or type of COVID-19 vaccines received, travellers should continue to follow the latest social distancing guidance, including any local requirements and maintain good hand, respiratory, and personal hygiene always.

All travellers returning to the UK will continue to follow COVID-19 testing and self-isolation requirements as proof of COVID vaccination does not alter any of the requirements for entry to the UK, including the need for hotel quarantine if returning from a "red list" country.

Falsified COVID-19 vaccines

The World Health Organization has identified falsified COVID-19 vaccine as posing a serious risk to global public health [9]. Substandard and falsified medical product alerts, are published by the WHO.

Overview of global COVID-19 vaccination programmes

There are a number of COVID-19 vaccines in clinical trials and preclinical development according to the World Health Organization.

As of 18th of June 2021, there are 16 vaccines being offered for general use worldwide as outlined below.

List of vaccines in use worldwide

No. Developer/Vaccine Status
1 Pfizer-BioNTech* Approved in several countries
2 Moderna* Approved in several countries
3 Gameleya (Sputnik V) Approved in several countries
4 Oxford AstraZeneca* Approved use in several countries
5 CanSinoBio Limited use in China
6 SinoPharm Approved in China, UAE, Bahrain and Egypt
7 Vector Institute Early use in Russia
8 SinoVac (Coronavac) Approved in China, Brazil and other countries
9 SinoPharm - Wuhan Limited use in China, U.A.E. and emergency use in other countries
10 Baharat Biotech (Covaxin) Emergency use in India, Iran, and other countries
11 Janssen/Johnson and Johnson* Approved in several countries
12 Novavax Limited use
13 Shenzhen Kangtai Emergency use in China
14 Coviran Barekat Emergency use in Iran
15 CureVac Limited use
16 EpiVacCorona Early use in Russia
* Indicates UK approved vaccines

Worldwide, as of 18th of June 2021, 193 countries have also implemented vaccination programmes with others planning to implement as shown in the map below.

COVID-19 Vaccination Programme Global Overview

A list of countries with COVID-19 Vaccination Programmes and their strategies where known is available here: Global COVID-19 Vaccination Programmes.

The vaccines landscape will be updated every 2 weeks.

First Published :   08 Dec 2020
Last Updated :   18 Jun 2021

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