Vaccine safety: Description of the adverse events reported to the surveillance system in Chile, 2014 to 2016

Abstract

Background: Passive surveillance systems for adverse events following immunization (AEFI) allow the monitoring of known adverse effects (AE) and the investigation of infrequent AE. Aim: To describe the AEFI notified in Chile between 2014 and 2016. Methodology: This was a study of epidemiological surveillance. A general analysis of AEFI and sub-analysis for pentavalent vaccine was carried out. It was calculated the global reporting rate of AEFI every 100,000 doses of vaccines, the reporting rate of AEFI considered of interest and the odds ratio of reporting (ROR) of apneas for pentavalent. Results: The total AEFI reported was 2,552 with a global reporting rate of 9,13. 13.4% of AEFI were serious. The vaccine reporting rate of events of interest was generally lower than the reference rates. The vaccine with the highest reporting rate (44.3) was pentavalent, with an ROR of apnea versus other vaccines of 10.5 (95% CI 3.77-29.47). Discussion: This study provides an overview of the AEFI notified in Chile. The global reporting rate was similar to other studies, but those of events of interest were lower than international references. A possible association between apnea and pentavalent vaccine is shown.