High SARS-CoV-2 attack rates among asymptomatic hospital workers from Ecuador

Abstract

Purpose: To determine the SARS-CoV-2 risk of infection in Ecuadorian hospital. This study aims to describe the SARS-CoV-2 attacks rate and viral loads among patient care workers and other staff from Ecuadorian hospitals during the first wave of COVID-19 pandemic. Methods & Materials: : Study design and setting. We carried out a cross-sectional study to describe the attack rate of SARS-CoV-2 infection among patient care workers (physicians, nurses and nursing assistants) and other healthcare personnel (administrative and services staff) from 9 hospitals of the Andean and Costal Regions of Ecuador from May to October 2020.Sample collection, RNA Extraction and RT-qPCR for SARS-CoV-2 diagnosis using the CDC protocol. The samples were processed in the BSL2 certified molecular biology laboratory at Universidad de Las Americas. Nasopharyngeal swabs were collected on 0.5mL TE pH 8 buffer for SARS-CoV-2 diagnosis by RT-qPCR following an adapted version of the CDC protocol.Statistical analysis. Chi cuadrado with the statistic program SPSS Results: A total of 1243 patient care workers and 428 of other healthcare staff were tested for SARS-CoV-2 infection. The SARS-CoV-2 attack rate was 12% (145/1243) for patient care workers and 19% (80/428) for other healthcare personnel, being this difference statistically significant (p<0.05). For each hospital, the following SARS-CoV-2 attack rates were obtained for patient care workers and other staff: 35% and 50% in “Hogar ABEI”, 21% and 26% in “Clínica Nuestra Señora de Guadalupe”, 15% and 18% in “Hospital de Atención Integral al Adulto Mayor”, 5% and 11% in “Hospital de Especialidades Eugenio Espejo”, 12% and 22% in “Hospital Geriátrico Dr. Bolívar Arguello”, 13% and 22% in “Hospital Dr. Gustavo Domínguez”, 22% and 12% in “Hospital General Dr. Napoleón Dávila”, 9% and 14% in “Hospital Pablo Arturo” and 5% and 13% in “Hospital San Francisco de Quito”. Moreover, we found 47 individuals (19 among patient care workers and 28 among other staff) with viral loads larger than 108 copies/mL that may be considered super spreaders. Conclusion: Ecuadorian hospital workers at a high-risk group for SARS-CoV-2 infection. Regular SARS-CoV-2 testing should be mandatory for this group as even asymptomatic SARS-CoV-2 super spreaders can be detected.