UK data, massive shift in vaccine risk / benefit analysis

Serious adverse events of special interest following mRNA COVID-19 vaccination in randomized trials in adult

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3.4. Harm-benefit considerations

In the Moderna trial,

the excess risk of serious AESIs was 15.1 per 10,000 participant

One in 662

(over placebo baselines)

In the Pfizer trial,

the excess risk of serious AESIs 10.1 per 10,000

One in 990

(over placebo baselines)

Combined, mRNA vaccines,

risk of serious adverse events of special interest

12.5 per 10,000 vaccinated

One in 800

(over placebo baselines)

1,250 serious events for each million vaccine recipients

Appendix 1: estimation of number needed to vaccinate to prevent a COVID-19 hospitalisation,

for primary vaccination,

booster vaccination (3rd dose),

autumn 2022 booster and,

spring 2023 booster (for those newly in a risk group)

(Published 25 January 2023)

Calculation of numbers needed to vaccinate (NNV)

Table 3: NNV for prevention of hospitalisation for different programmes

20 – 29 Years, Autumn booster

No risk group, 169,200 (706,500)

In a risk group, 7,500 (59,500)

50 – 59 Years, Autumn booster

No risk group, 43,600 (256,400)

In a risk group, 3,100 (18,600)

60 – 69 years, Autumn booster

3,600 (27,300)

70 + Autumn booster

800 (7,500)

Table 1: rates per million of COVID-19 hospitalisation (rates are for July 2022)

1,250 serious events for each million vaccine recipients

Table 1: rates per million of COVID-19 severe hospitalisation (rates are for July 2022)

1,250 serious events for each million vaccine recipients

Based on a UK Health Security Agency (UKHSA) presentation to the Joint Committee on Vaccination and Immunisation (JCVI) on 25 October 2022.