Adverse events of the vaccine against SARS-CoV-2 in an Uruguayan pediatric sample

Abstract

In our country, in children aged 5 and 11 years, the use of the Pfizer/BioNTech vaccine has been recommended since December/2021, in two doses separated by six weeks. Further vaccine evaluation is necessary due to its rapid approval process.
The aim of this study was to determine the occurrence of events supposedly attributable to vaccination or immunization (ESAVI) against the SARS-CoV-2 in children from 5 and 11 years.
A descriptive study was carried out. Children under 12 years of age were included with blood tests ordered by the doctor in the laboratory of the Pereira Rossell Hospital Center between November 2021/2022. Data were collected on: ESAVI, vaccination status, age and sex through a survey and clinical history. The variables were analyzed by descriptive statistics.
There were 141 children between 5 and younger than 12 years who participated in the study; of these, 53.9% (n=74) received the vaccine. Their mean age was 8.4 (2.1) years and 47.3% were female. The most frequent ESAVI after the first dose were: general discomfort (n=8) and headache (n=9). In the vaccination area, they were: pain (n=30) and hardening (n=10). In the second dose, the most frequent were: headache and fever (n=3) and the local ones were: pain (n=13) and hardening (n=4).
These symptoms occurred more frequently in the first three days post-vaccination in both doses.
These results allow us to conclude that the ESAVI found were mild, more frequently local and in a short post-vaccination period.