Factors Associated with Not Receiving a Booster Dose of COVID-19 Vaccine in Peru.

To determine the factors associated with not receiving the booster dose for COVID-19 in Peru, a cross-sectional study by secondary analysis of a University of Maryland and Facebook survey database assessing the global impact of COVID-19 was conducted. Data of Peruvian users of this social network over 18 years of age who answered the survey between 13 February 2022 and 14 April 2022 were analyzed. We evaluated the association between sociodemographic characteristics, comorbidities, and history of COVID-19 with having received a booster dose for COVID-19. Crude (cPR) and adjusted (aPR) prevalence ratios with their respective 95% confidence intervals (95%CI) were calculated. A sample of 20,814 adults, 21.5% of whom reported not receiving the booster dose, was analyzed. People under 75 years of age had a higher prevalence of not having received the booster dose. Likewise, having a university education (aPR = 1.03; 95%CI: 1.02-1.05), secondary, or pre-university education (aPR = 1.07; 95%CI: 1.05-1.09), or having a primary level or less (aPR = 1.11; 95%CI: 1.05-1.18), were associated with a higher prevalence of not receiving the booster, compared to individuals with a postgraduate education. Being employed (aPR = 1.01; 95%CI: 1.00-1.02), having had COVID-19 (aPR = 1.03; 95%CI: 1.01-1.04) and living in a town (aPR = 1.05; 95%CI: 1.02-1.07) or in a rural area (aPR = 1.06; 95%CI: 1.03-1.10), compared to living in the city, had a similar association. On the contrary, the female gender was associated with a lower prevalence of not receiving the booster (aPR = 0.97; 95%CI: 0.96-0.99). Sociodemographic characteristics and a history of having had COVID-19 were associated with the probability of not having received the booster dose for COVID-19 in the Peruvian population.