Seroepidemiology of SARS-CoV-2 in healthcare personnel working at the largest tertiary COVID-19 referral hospitals in Mexico City.

INTRODUCTION: We performed a longitudinal SARS-CoV-2 seroepidemiological study in healthcare personnel of the two largest tertiary COVID-19 referral hospitals in Mexico City. METHODS: All healthcare personnel, including staff physicians, physicians in training, nurses, laboratory technicians, researchers, students, housekeeping, maintenance, security, and administrative staff were invited to voluntarily participate, after written informed consent. Participants answered a computer-assisted self-administered interview and donated blood samples for antibody testing every three weeks from October 2020 to June 2021. RESULTS: A total of 883 participants (out of 3639 registered employees) contributed with at least one blood sample. The median age was 36 years (interquartile range: 28-46) and 70% were women. The most common occupations were nurse (28%), physician (24%), and administrative staff (22%). Two hundred and ninety participants (32.8%) had a positive-test result in any of the visits, yielding an overall adjusted prevalence of 33.5% for the whole study-period. Two hundred and thirty-five positive tests were identified at the baseline visit (prevalent cases), the remaining 55 positive tests were incident cases. Prevalent cases showed associations with both occupational (institution 2 vs. 1: adjusted odds ratio [aOR] = 2.24, 95% confidence interval [CI]: 1.54-3.25; laboratory technician vs. physician: aOR = 4.38, 95% CI: 1.75-10.93) and community (municipality of residence Xochimilco vs. Tlalpan: aOR = 2.03, 95% CI: 1.09-3.79) risk-factors. The incidence rate was 3.0 cases per 100 person-months. Incident cases were associated with community-acquired risk, due to contact with suspect/confirmed COVID-19 cases (HR = 2.45, 95% CI: 1.21-5.00). CONCLUSIONS: We observed that between October 2020 and June 2021, healthcare workers of the two largest tertiary COVID-19 referral centers in Mexico City had similar level of exposure to SARS-CoV-2 than the general population. Most variables associated with exposure in this setting pointed toward community rather than occupational risk. Our observations are consistent with successful occupational medicine programs for SARS-CoV-2 infection control in the participating institutions but suggest the need to strengthen mitigation strategies in the community.

Clinical Characteristics and Mortality of Health-Care Workers With Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in Mexico City.

BACKGROUND: We evaluated the risk of death for health-care workers (HCW) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Mexico City during the coronavirus disease 2019 (COVID-19) pandemic, and describe the associated factors in hospitalized HCW, compared with non-HCW. METHODS: We analyzed data from laboratory-confirmed SARS-CoV-2 cases registered from 27 February-31 August 2020 in Mexico City's public database. Individuals were classified as non-HCW or HCW (subcategorized as physicians, nurses, and other HCW). In hospitalized individuals, a multivariate logistic regression model was used to analyze the potential factors associated with death and compare mortality risks among groups. RESULTS: A total of 125 665 patients were included. Of these, 13.1% were HCW (28% physicians, 38% nurses, and 34% other HCW). Compared with non-HCW, HCW were more frequently female, were younger, and had fewer comorbidities. Overall, 25 771 (20.5%) were treated as inpatients and 11 182 (8.9%) deaths were reported. Deaths in the total population (9.9% vs 1.9%, respectively; P < .001) and in hospitalized patients (39.6% vs 19.3%, respectively; P < .001) were significantly higher in non-HCW than in HCW. In hospitalized patients, using a multivariate model, the risk of death was lower in HCW in general (odds ratio [OR], 0.53) than in non-HCW, and the risks were also lower by specific occupation (OR for physicians, 0.60; OR for nurses, 0.29; OR for other HCW 0.61). CONCLUSIONS: HCW represent an important proportion of individuals with SARS-CoV-2 infection in Mexico City. While the mortality risk is lower in HCW compared to non-HCW, a high mortality rate in hospitalized patients was observed in this study. Among HCW, nurses had a lower risk of death compared to physicians and other HCW.

CLINICAL AND EPIDEMIOLOGICAL CHARACTERISTICS OF PATIENTS DIAGNOSED WITH COVID-19 IN A TERTIARY CARE CENTER IN MEXICO CITY: A PROSPECTIVE COHORT STUDY.

BACKGROUND: Regional information regarding the characteristics of patients with coronavirus disease (COVID)-19 is needed for a better understanding of the pandemic. OBJECTIVE: The objective of the study to describe the clinical features of COVID-19 patients diagnosed in a tertiary-care center in Mexico City and to assess differences according to the treatment setting (ambulatory vs. hospital) and to the need of intensive care (IC). METHODS: We conducted a prospective cohort, including consecutive patients with COVID-19 from February 26, 2020 to April 11, 2020. RESULTS: We identified 309 patients (140 inpatients and 169 outpatients). The median age was 43 years (interquartile range, 33-54), 59.2% men, and 18.6% healthcare workers (12.3% from our center). The median body mass index (BMI) was 29.00 kg/m2 and 39.6% had obesity. Compared to outpatients, inpatients were older, had comorbidities, cough, and dyspnea more frequently. Twenty-nine (20.7%) inpatients required treatment in the IC unit (ICU). History of diabetes (type 1 or 2) and abdominal pain were more common in ICU patients compared to non-ICU patients. ICU patients had higher BMIs, higher respiratory rates, and lower room-air capillary oxygen saturations. ICU patients showed a more severe inflammatory response as assessed by white blood cell count, neutrophil and platelet count, C-reactive protein, ferritin, procalcitonin, and albumin levels. By the end of the study period, 65 inpatients had been discharged because of improvement, 70 continued hospitalized, and five had died. CONCLUSIONS: Patients with comorbidities, either middle-age obese or elderly complaining of fever, cough, or dyspnea, were more likely to be admitted. At admission, patients with diabetes, high BMI, and clinical or laboratory findings consistent with a severe inflammatory state were more likely to require IC.