Valladares-Garrido, vZeña-Ñañez, SandraPeralta, C IchiroPuicón-Suárez, Jacqueline BDíaz-Vélez, CristianFailoc-Rojas, Virgilio E2022-11-082022-11-082022-05-20https://hdl.handle.net/20.500.13053/7017COVID-19 vaccines have achieved a significant reduction in mortality, yet objective estimates are needed in specific settings. We aimed to determine the effectiveness of COVID-19 vaccination at a referral hospital in Lambayeque, Peru. We conducted a retrospective cohort study from February to September 2021. We included hospitalized patients with COVID-19, whose data were stored in NotiWeb, a patient data system of the Peruvian Ministry of Health. We applied a propensity score-weighting method according to baseline characteristics of patients, and estimated hazard ratios (HR) using Cox regression models. Of 1553 participants, the average age was 55 years (SD: 16.8), 907 (58%) were male, and 592 (38%) deceased at 28-day follow-up. Before hospital admission, 74 (4.8%) had been immunized with at least one vaccine dose. Effectiveness against death in vaccinated patients was 50% at 90-day follow-up (weighted HR 0.50, 95% CI 0.28-0.89). Our results support the effectiveness of COVID-19 vaccination against death and provide information after early immunization in Peru.application/pdfenginfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by/4.0/COVID-19; Peru; mortality; vaccination; vaccine effectiveness.info:eu-repo/semantics/articlehttps://doi.org/10.3390/vaccines10050812http://purl.org/pe-repo/ocde/ford#3.03.00