TY - JOUR T1 - Clinical and serological profile of asymptomatic and non-severe symptomatic COVID-19 cases: Lessons from a longitudinal study in primary care in Latin America JF - BJGP Open JO - BJGP Open DO - 10.3399/bjgpopen20X101137 SP - bjgpopen20X101137 AU - Klaus Puschel AU - Catterina Ferreccio AU - Blanca PeƱaloza AU - Katia Abarca AU - Maria-Paulina Rojas AU - Alvaro Tellez AU - Philippa Moore AU - Ana Maria Cea AU - Carlos Wilson AU - Vicente Cid AU - Joaquin Montero Y1 - 2021/01/13 UR - http://bjgpopen.org/content/early/2021/01/11/bjgpopen20X101137.abstract N2 - Background Chile has one of the highest incidences of COVID-19 infection in the world. Primary care can play a key role in early detection and containment of the disease. There is a lack of information on the clinical profile of patients with suspected COVID-19 in primary care, and controversy on the effectiveness of rapid serologic tests in the diagnosis and surveillance of the disease.Aim To assess the effectiveness of rapid serologic testing in detection and surveillance of COVID-19 cases in primary care.Design & setting A longitudinal study was undertaken, which was based on a non-random sample of 522 participants, including 304 symptomatic patients and 218 high-risk asymptomatic individuals. They were receiving care at four primary health clinics in an underserved area in Santiago, Chile.Method The participants were systematically assessed and tested for COVID-19 with reverse transcriptase-polymerase chain reaction (RT-PCR) and serology at baseline, and were followed clinically and serologically for 3 weeks.Results The prevalence rate of RT-PCR confirmed COVID-19 cases were 3.5 times higher in symptomatic patients (27.5%; 95% confidence interval [CI] = 22.1 to 32.8) compared with asymptomatic participants (7.9%; 95% CI = 4.3 to 11.6). Similarly, the immune response was significantly different between both groups. Sensitivity of serologic testing was 57.8% (95% CI = 44.8 to 70.1) during the third week of follow-up and specificity was 98.4% (95% CI = 95.5 to 99.7).Conclusion Rapid serologic testing is ineffective for detecting asymptomatic or non-severe cases of COVID-19 at early stages of the disease, but can be of value for surveillance of immunity response in primary care. The clinical profile and immune response of patients with COVID-19 in primary care differs from those in hospital-based populations. ER -