The prevalence of asymptomatic and symptomatic COVID-19 in a cohort of quarantined subjects

Background: The frequency of asymptomatic SARS-CoV-2 infection with viral spread is unclear. Asymptomatic SARS-CoV-2 infection development and progression was investigated in subjects undergoing mandatory quarantine on airport arrival.Methods: 2714 subjects were tested for SARS-CoV-2 and all were quarantined for 2 weeks. Viral retesting was undertaken on symptom development and routinely at 14 days if asymptomatic. Asymptomatic, positive patients underwent viral testing every 2 days to determine viral clearance.Results: 188/2714 (6.9%) patients became SARS-CoV-2 positive. On arrival, 136/188 tested positive, with 44/188 (23.4%) symptomatic and 92/188 (48.9%) asymptomatic. All 92 patients remained asymptomatic and were retested every 2 days until viral clearance. 2526 quarantined subjects remained virus free at 14 days. Viral clearance did not differ between symptomatic and asymptomatic patients (12.6 ± 1.0 days and 12.1 ± 0.4 days, respectively). Of the 52/188 (27.7%) testing negative on arrival, 27/52 subsequently became positive and developed symptoms 2-13 days after arrival. 25/188 (13.3%) remained asymptomatic and tested positive at day 14, with viral testing undertaken every 2 days in these subjects; of these, 24 remained asymptomatic, with viral clearance at 9.4 ± 0.7 days - less than for those who were asymptomatic on arrival (p Conclusion: Asymptomatic patients with COVID-19 were more prevalent than those exhibiting symptoms, and are an infection reservoir.</p

Time till viral clearance of Severe Acute Respiratory Syndrome Coronavirus 2 is similar for asymptomatic and non-critically symptomatic individuals.

Despite the modeled estimations of the burden of asymptomatic spread, the duration of viral positivity and infectiousness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains understudied. The objective of the present study was to estimate and compare the time till viral clearance of SARS-CoV-2 in asymptomatic and non-critical symptomatic individuals. We studied 184 SARS-CoV-2-positive participants, of whom 145 were asymptomatic. Our analysis uncovered that time till viral negativity is similar for subclinical [median time till viral clearance: 11 days, interquartile range (IQR): 8, 14] and overt infections (median: 11 days, IQR: 9, 14) after controlling for age and sex. This has implications in understanding the period of infectivity for SARS-CoV-2 in order to plan adequate public health measures to control the community spread

COVID-19 and sickle cell disease in Bahrain

Introduction: Coronavirus disease 2019 (COVID-19) is caused by a newly identified strain of the coronavirus family that has been shown to affect the hemoglobin beta chain, the same chain that has sickle cell disease (SCD) mutation. This study was undertaken to see if COVID-19 infection increased disease severity in patients with SCD.Methods: Mass screening of the Bahraini population was undertaken between February and April 2020.Results: A total of 38,092 Bahraini people were tested for COVID-19 during this period; 378 (1%) were SCD patients. Six patients with SCD had COVID-19 (1.6%): three remained asymptomatic, two had mild symptoms and one required oxygen therapy. The SCD patients had a similar average length of stay when compared with non-SCD COVID-19 patients (10.7 days).Conclusion: The infection rate, clinical course and viral clearance seen for the SCD patients with COVID-19 were no different to those without SCD.</p