COVID-19 outbreak at a large homeless shelter in Boston: Implications for universal testing

Abstract

The circumstances of homelessness create the potential for rapid transmission of SARS-CoV-2 in this vulnerable population. Upon observing a cluster of COVID-19 cases from a single large homeless shelter in Boston, Boston Health Care for the Homeless Program conducted symptom assessments and polymerase chain reaction (PCR) testing for SARS-CoV-2 among all guests residing at the shelter over a 2-day period. Of 408 participants, 147 (36.0%) were PCR-positive for SARS-CoV-2. COVID-positive individuals were more likely to be male (p<0.001) but did not differ significantly from COVID-negative individuals with respect to other demographic and clinical characteristics. Cough (7.5%), shortness of breath (1.4%), and fever (0.7%) were all uncommon among COVID-positive individuals. Our findings illustrate the rapidity with which COVID-19 can be widely transmitted in a homeless shelter setting and suggest that universal PCR testing, rather than a symptom triggered approach, may be a better strategy for identifying and mitigating COVID-19 among people experiencing homelessness.

Group testing for SARS-CoV-2 allows for up to 10-fold efficiency increase across realistic scenarios and testing strategies

“…Another study conducted in a homeless shelter in Boston, MA, USA, confirmed that standard COVID-19 symptoms like cough, shortness of breath, and fever were uncommon among individuals who tested positive and strongly argues for universal PCR testing on that basis. 71 Also, besides enhancing the tests of mild/asymptomatic cases, some disease control centers, such as the ECDC, recommend that group testing should potentially be applied to prevalence studies. 72 The pooling schemes suggested here can also include routine tests of cohesive subpopulations with high prevalence, such as health care workers, and therefore propose a sensible way to include commonly available information about risk group into the setup.…”

“…The importance of such estimates described above lead to a recent collaborative effort between FIND, a Swiss foundation for diagnostics, and the World Health Organization for the COVID-19 pandemic in order to evaluate the qRT-PCR tests and to assess their accuracy. 42 FIND is currently evaluating a list of more than 300 SARS-CoV-2 tests commercially available and to establish accurate estimates for sensitivity and specificity with their respective confidence intervals. 43 Based on the preliminary findings, in this work we will assume that the specificity of a single PCR test is 99%.…”

Vitamin D insufficiency is prevalent in severe COVID-19

“…2 In a Boston homeless shelter, 100% of 147 COVID-19 positive subjects were asymptomatic. 3 The mechanisms underlying severe COVID-19 should account for both these findings, as well as other COVID-19 mortality risk factors: hypertension, obesity, male sex, advanced age, concentration in northern climates, and COVID-19 associated coagulopathy (CAC). 4,5 Vitamin D insufficiency (VDI) meets every one of the above criteria.…”

Brazilian Modeling of COVID-19(BRAM-COD): a Bayesian Monte Carlo approach for COVID-19 spread in a limited data set context

“…The study by Ferguson et al [34] assumed that 50% of the infected individuals could be asymptomatic. Recent evidence shows the possibility of a greater number of asymptomatic patients [44,45,26,11]. Thus, we created a correction factor to the table described by Verity et al [31] based on the work of Ioannidis et al [22] and adapted it for the relative risk of ICU-level care and death according to age and asymptomatic percentage.…”