Abstract
Background: There is an urgent need to understand the dynamics and risk factors driving ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission during shelter-in-place mandates.
Methods: We offered SARS-CoV-2 reverse-transcription polymerase chain reaction (PCR) and antibody (Abbott ARCHITECT IgG) testing, regardless of symptoms, to all residents (aged ≥4 years) and workers in a San Francisco census tract (population: 5174) at outdoor, community-mobilized events over 4 days. We estimated SARS-CoV-2 point prevalence (PCR positive) and cumulative incidence (antibody or PCR positive) in the census tract and evaluated risk factors for recent (PCR positive/antibody negative) vs prior infection (antibody positive/PCR negative). SARS-CoV-2 genome recovery and phylogenetics were used to measure viral strain diversity, establish viral lineages present, and estimate number of introductions.
Results: We tested 3953 persons (40% Latinx; 41% White; 9% Asian/Pacific Islander; and 2% Black). Overall, 2.1% (83/3871) tested PCR positive: 95% were Latinx and 52% were asymptomatic when tested; 1.7% of census tract residents and 6.0% of workers (non-census tract residents) were PCR positive. Among 2598 tract residents, estimated point prevalence of PCR positives was 2.3% (95% confidence interval [CI], 1.2%-3.8%): 3.9% (95% CI, 2.0%-6.4%) among Latinx persons vs 0.2% (95% CI, .0-.4%) among non-Latinx persons. Estimated cumulative incidence among residents was 6.1% (95% CI, 4.0%-8.6%). Prior infections were 67% Latinx, 16% White, and 17% other ethnicities. Among recent infections, 96% were Latinx. Risk factors for recent infection were Latinx ethnicity, inability to shelter in place and maintain income, frontline service work, unemployment, and household income <$50 000/year. Five SARS-CoV-2 phylogenetic lineages were detected.
Conclusions: SARS-CoV-2 infections from diverse lineages continued circulating among low-income, Latinx persons unable to work from home and maintain income during San Francisco’s shelter-in-place ordinance.
Keywords: asymptomatic SARS-CoV-2 infection; community-based SARS-CoV-2 testing; ethnic disparities; phylogenetic analysis; shelter-in-place.
【저자키워드】 Phylogenetic analysis, asymptomatic SARS-CoV-2 infection, community-based SARS-CoV-2 testing, ethnic disparities, shelter-in-place, 【초록키워드】 SARS-CoV-2, IgG, coronavirus, Risk factors, antibody, SARS-COV-2 infection, Infection, Transmission, risk factor, severe acute respiratory syndrome Coronavirus, Symptoms, Prevalence, polymerase chain reaction, Phylogenetic analysis, infections, PCR, Asymptomatic, SARS-CoV-2 genome, Lineage, phylogenetics, incidence, SARS-CoV-2 infections, cumulative incidence, Phylogenetic, Abbott, San Francisco, Chain Reaction, point prevalence, viral strain, census tract, black, acute respiratory syndrome, Factor, 95% CI, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, 95% confidence interval, PCR positive, income, white, unemployment, viral lineages, circulating, cumulative, driving, Latinx, event, polymerase chain, Latinx ethnicity, tested, evaluated, were used, maintain, Estimated, offered, viral lineage, 【제목키워드】 coronavirus 2, Population, respiratory,