Thread by @petermbenglish

@sweetanimo @patricia_stoop @abcdiagnosis I have seen some of your conversation on Twitter about the use of Covid-19 vaccines in people who are immune-suppressed, and thought I might be able to help.
1/11

First, the UK guidance, including on contraindications etc., is conveniently all in one place - in the public domain - in the "Green Book", via gov.uk/government/pub…
2/11

But first, let's consider how and why immunosuppression might be an issues with a vaccine.
3/11

The first, and most obvious issue, is that people with a suppressed or faulty immune system might fail to respond as well as other people - or at all - to a vaccine.

This is not a reason for not having the vaccine at all; just a warning that it might work.
4/11

And of course, people who are immune-suppressed may well (for that reason) be at greater risk from infectious diseases. So vaccination - even if less likely to be effective - might be particularly recommended; it can be one of the reasons for vaccinating.
5/11

The other issue is that a some vaccines - not the Covid-19 ones - may be more risky in immune-suppressed people because they are weakened versions of the infectious agent, harmless in people with a healthy immune system.
6/11

In a tiny proportion of immune-suppressed recipients, such vaccines can cause disease. Examples include BCG (bacterial vaccine against TB), some chickenpox and shingles vaccines (not universally used in the UK), and the components of MMR.
7/11

The relevant sections of the Green Book are on p14 - on immunosuppression and on contraindications.
8/11

They make it very clear that the Covid-19 vaccines (at least, the ones due to be licensed in the UK in the near future) are NOT attenuated live virus vaccines. They cannot reproduce or replicate in the body, so they cannot cause an infection.
9/11

As they cannot reproduce in the body, and cannot cause infection, there is no need to withhold them because of immune-suppression per se.
10/11

I cannot comment on why some consultant oncologists might be concerned about these vaccines - my speciality is public health and I'm a vaccines expert, not an oncologist; but immunosuppression is not the reason.
11/11

@threadreaderapp unroll

Are any immunologists or oncologists able to comment on why people think Covid-19 vaccines are contraindicated? (Full thread available at threadreaderapp.com/thread/1334838… or a version on my blog peterenglish.blogspot.com/2020/11/vaccin… )