Seroprevalence of SARS-CoV-2 among Blood Donors and Changes after Introduction of Public Health and Social Measures, London, UK

Abstract

T he fi rst confi rmed cases of coronavirus disease (COVID-19) in the United Kingdom were identifi ed at the end of January 2020. As cases increased across all regions, surveillance data indicated that the epidemic was progressing more rapidly in London than the rest of the United Kingdom. In response to the increase in cases, hospitalizations, and deaths, the United Kingdom introduced a series of measures to limit transmission, beginning March 12, 2020 (week 11); persons with a continuous cough or fever were advised to self-isolate for 7 days, school trips abroad were cancelled, and at-risk groups were advised to avoid cruises. These measures culminated in the implementation of legally enforceable public health and social measures (i.e., lockdown) beginning March 23 (week 13) (1).Despite the reporting of a range of surveillance data in England, including laboratory-confi rmed cases, primary-care consultations, hospital and intensive care unit (ICU) admissions, and deaths (2), much remains unknown about the magnitude of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus in the population, the key drivers of transmission, and the incidence of asymptomatic or mildly symptomatic infection within the UK population thus far.Serologic estimates are critical to better understand epidemiologic trends and help inform policy options to control disease. These estimates also provide a denominator for estimating severity measures, such as infection fatality and infection hospitalization ratios, and to help clarify the epidemiology of COV-ID-19 in the population.Early in the pandemic, data from populationbased seroepidemiologic studies were limited (N. Bobrovitz et al., unpub. data,

SARS Antibody Testing in Children: Development of Oral Fluid Assays for IgG Measurements

“…Oral fluids were analyzed with an in-house EIA established for analysis of sera ( 40 , 44 ), which had been validated to guidelines by the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) ( 45 ) in the early period of the pandemic and used for research purposes within our institute. It shows 93% sensitivity and 98% specificity, results that have been described in peer-reviewed publications ( 40 , 46 ). Through checkerboard titration experiments, this indirect EIA was modified to allow analysis of oral fluids as follows: 96-well microtiter plates (Nunc, catalog no.…”

Social Distancing during COVID-19 Pandemic among Inflammatory Bowel Disease Patients

“…Most studies available to date are based on the assessment of symptomatic COVID-19 cases [13][14][15]. Only a few have looked at asymptomatic cases, the numbers of which are very high for the SARS-CoV-2 virus and critical to the maintenance of the pandemic [11,12,[16][17][18]. The present study focuses on the assessment of asymptomatic cases or contact of patients with an infected person, expressed by antibody seroprevalence.…”

“Salus Populi Suprema Lex”: Considerations on the Initial Response of the United Kingdom to the SARS-CoV-2 Pandemic

“…However, it certainly requires of being taken into account when an accurate assessment with a rigorous multivariate statistical model in the context of a properly designed study will be performed. An in-depth analysis including serological estimates in relation to hospitalizations and ICU admissions ( 25 ) will remain scientifically and socially necessary in order to better understand the evolution of the pandemic in the UK and elsewhere; thus implementing the adequate corrections to the healthcare services and increasing the compliance of the population to new stringent measures aimed to control further waves of the pandemic. More importantly, it would be a valid reassurance for the British population, clarifying whether any selection bias has been applied to prevent the overwhelming of the NHS as it seems that might have happened ( 26 ).…”