UK COVID vaccine update


The vaccine situation is fluid we are on version 4 of the green book 14a

Both of the early COVID-19 vaccines are considered inactivated (including the nonreplicating adenovirus vaccine)


Pfizer BioNTech COVID-19 mRNA Vaccine BNT162b2
The dose of Pfizer BioNTech COVID-19 vaccine is 30µg contained in 0.3ml of the diluted vaccine. After dilution each multidose vial can be used to deliver five or six doses of 0.3ml. The vaccine should be administered in 2 doses, a minimum of 21 days apart.
AstraZeneca COVID-19 vaccine
The dose of AstraZeneca COVID-19 vaccine is 0.5ml. The vaccine should be administered in 2 doses, a minimum of 28 days apart.

Operationally, it is recommended that the second dose of both vaccines should be routinely scheduled between four and 12 weeks after the first dose. This will allow more people to benefit from the protection provided from the first dose during the roll out phase. Longer term protection will then be provided by the second dose. If an interval longer than the recommended interval is left between doses, the second dose should still be given (preferably using the same vaccine as was given for the first dose if possible). The course does not need to be restarted.

Previous incomplete vaccination
If the course is interrupted or delayed, it should be resumed using the same vaccine but the first dose should not be repeated. There is no evidence on the interchangeability of the COVID-19 vaccines although studies are underway. Therefore, every effort should be made to determine which vaccine the individual received and to complete with the same vaccine.
For individuals who started the schedule and who attend for vaccination at a site where the same vaccine is not available, or if the first product received is unknown, it is reasonable to offer one dose of the locally available product to complete the schedule. This option is preferred if the individual is likely to be at immediate high risk or is considered
unlikely to attend again. In these circumstances, as both the vaccines are based on the spike protein, it is likely the second dose will help to boost the response to the first dose. For this reason, until additional information becomes available, further doses would not then be required.

Individuals who are participating in a clinical trial of COVID-19 vaccines who present for vaccination should be referred back to the investigators. Eligible persons who are enrolled in vaccine trials should then be provided with written advice on whether and when they can be safely vaccinated in the routine programme.

Co-administration with other vaccines
Although no data for co-administration of COVID-19 vaccine with other vaccines exists, in the absence of such data first principles would suggest that interference between inactivated vaccines with different antigenic content is likely to be limited. Based on experience with other vaccines any potential interference is most likely to result in a slightly attenuated immune response to one of the vaccines. There is no evidence of any safety
concerns, although it may make the attribution of any adverse events more difficult.
Because of the absence of data on co-administration with COVID-19 vaccines, it should not be routine to offer appointments to give this vaccine at the same time as other vaccines. Based on current information about the first COVID-19 vaccines being deployed, scheduling should ideally be separated by an interval of at least 7 days to avoid incorrect
attribution of potential adverse events.

Individuals who have immunosuppression and HIV infection (regardless of CD4 count) should be given COVID-19 vaccine in accordance with the recommendations and contraindications above. Although AstraZeneca COVID-19 vaccine contains a live adenovirus vector, this virus is not replicating and is considered safe in immunosuppressed people

There are very few individuals who cannot receive the Pfizer-BioNTech or AstraZeneca COVID-19 vaccines. Where there is doubt, rather than withholding vaccination, appropriate advice should be sought from the relevant specialist, or from the local immunisation or health protection team.

The vaccine should not be given to those who have had a previous systemic allergic reaction (including immediate-onset anaphylaxis) to:
● a previous dose of the same COVID-19 vaccine
● any component (excipient) of the COVID-19 vaccine

The Pfizer BioNTech COVID-19 mRNA Vaccine BNT162b2 contains polyethylene glycol (PEG), which is from a group of known allergens commonly found in medicines (e,g plegridy) and also in household goods and cosmetics. Known allergy to PEG is extremely rare but would contraindicate receipt of this vaccine. (Sellaturay P et al, 2020).

PEG is also an excipient in the Moderna mRNA COVID-19 vaccine;
individuals who have a systemic allergic reaction to the Pfizer-BioNTech vaccine should not be given a dose of the Moderna vaccine, and vice versa.

Patients with undiagnosed PEG allergy may havea history of unexplained anaphylaxis or of anaphylaxis to multiple classes of drugs (see
precautions). The AstraZeneca vaccine does not contain PEG and is a suitable alternative.

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  • What would the effect be if someone is vaccinated while they have a case of COVID (given the # people that are asymptotic)?

    • Probably not much of an effect as the vaccine will take about 1-2 weeks to work and most people get rid of the virus within a week. However, if there is a high antibody response, which often doesnt occur in asymptomatic disease, it will get rid of the the vaccine protein and may make it less effective

  • Great post!

    I’m just not sure (and a bit anxious) about potentially being offered a different vaccine at my upcoming 2nd dose of vaccine. I understand the logistical reasoning for delaying 2nd dose – I.e. to open up slots for other people to have their vaccines & get more of the population vaccinated pronto…. but having half a course of 2 vaccines does not seem appealing!

    • Where in the world are you and what age are you? I just wondered how you had already had one vaccination

    • I think it gives an indication about how concerned the Government is with the current situation, however it could be a plus point because if you get the virus some of the immune response is to the virus and one second injection may increase injection rection, although it says second injection gives less of a reaction, this is why zeneca looking into getting the sputnik 5 adenovirus approved in russia. However remember most doses will be with the zeneca/oxford vaccine

  • Can please you clarify 2 concerns for me?
    1. Alemtuzumab patients advised never to have a live vaccine, are all 3 vaccines safe to have?
    2. All 3 vaccine’s notes mention concern if patient has thrombocytopenia – in what respect please?
    Many thanks for all the information MD, much appreciated.

    • 1. I dont think it is correct about live vaccines once you have repopulated there is not reason why you are any different from someone who hasnt had alemtuzumab the risk is in the first few months after infusion hower,
      2. It doesn’t matter because none of the vaccines are considered to be live within the UK and are all considered to be safe.
      3. Thrombocytopenia I think is to do with clotting, if you don’t haveplatelets you can’t clot as they dont want you to bleed to death from a needle prick.

      • Many thanks for reply. These are the answers I was hoping for in order to have the vaccine as soon as it becomes available for me & without a battle with hcp over which vaccine to have. Much appreciated.

  • Can I ask you something? Due to risk of permanent worsening, I avoid respiratory infections like the plague.

    Vaccines stimulate the immune system, why is this not also damaging?

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