The cases of rash on mRNA vaccines are almost non-existent and no deaths have occurred.

A research published in the medical journal JAMA, points out that the probability of developing anaphylaxis is only 0.000377%, as out of the approximately 17.5 million vaccinations, no deaths occurred, while only 66 people developed anaphylaxis to mRNA vaccines.

A report on rash cases recorded in America was published yesterday in the medical journal JAMA . The report covers the period from December 14 to January 18 and the administration of a total of 9,943,247 doses of the Pfizer vaccine and 7,581,429 doses of the Moderna vaccine.

This is a total of 66 cases – 4.5 cases per million doses of the Pfizer vaccine and 2.5 per million doses of the Moderna vaccine. The vast majority of cases were reported after the first dose of the vaccine (54 after the first dose, 5 after the second dose and there was no accurate record of 7 cases).
44 of the 47 cases recorded for the Pfizer vaccine occurred in women, as did all Moderna cases.

Of the 66, 21 were observed in people with a history of previous anaphylaxis and 89% of cases occurred in less than 30 minutes.

Vaccine instructions (US Centers for Disease Control – CDC) include 15- or 30-minute follow-up for people with or without a history of anaphylaxis, respectively. The results show that this period is usually long enough: 32 of the 66 cases required hospitalization, and 7 were intubated. In 6 of the 7 intubated patients – who belonged to the anaphylaxis group – the time from vaccination to reaction was less than 11 minutes. The duration of hospitalization for those who needed to be hospitalized was 1 to 3 days.

So what do we learn from this report?

After about 18 million vaccinations we know that the chance of someone developing anaphylaxis in the vaccine is 0.000377%, there were no deaths and almost all episodes of anaphylaxis occurred in the first 11 minutes after vaccination. 

Note that despite the very low incidence of anaphylaxis, it is very important that vaccination centers always have adequate adrenaline, corticosteroids and antihistamines to treat such cases. 

Finally, according to the report, the duration of the anaphylaxis that required intubation was 1-45 ‘after the vaccination, although 6 out of 7 occurred in the first 11 minutes. In this light, it would be advisable for people with a history of anaphylaxis to stay in or near the vaccination site, with a relative, for up to 45 minutes.