Limited large-scale studies have been conducted to investigate the adverse effects of COVID-19 vaccine in Latin America, particularly among the healthcare worker (HCW) population in Ecuador. The objective of this study was to assess a cohort of Ecuadorian healthcare workers for adverse reactions following vaccination with the Pfizer-BioNTech vaccine.

The COVID-19 pandemic bears a burden on medical care and economies worldwide, however immunization at the population level provides a way for to reduce future morbidity and mortality. Vaccine hesitancy and reluctance in getting the COVID-19 vaccine and apprehensions about them have been present along the course of vaccination programs and mass immunizations across the world. Factors such as the quick, large-scale production of vaccines, lack of information, and uncertainty about adverse reactions in the public's eye as well about myths spreading through media channels have given rise to suspicion and fear in the Latin American population. Limited large-scale studies have been conducted to investigate the adverse effects of COVID-19 vaccine in Latin America, particularly among the healthcare worker (HCW) population in Ecuador. The objective of this study was to assess a cohort of Ecuadorian healthcare workers for adverse reactions following vaccination with the Pfizer-BioNTech vaccine.

Inclusion Criteria:

• Ecuadorian nationality
• Active practice in the medical field
• Received the Pfizer-BioNTech COVID-19 vaccine

Exclusion Criteria:

• Patients who voluntarily refused to participate.

The population included Ecuadorian healthcare workers who received the inoculation with the Pfizer-BioNTech COVID-19 vaccine.