Mass screening is a key component to fight against SARS-CoV-2 and return to normalcy

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had highly transmissible and pathogenic, which caused serious economic loss and hazard to public health. Different countries have developed strategies to deal with the COVID-19 pandemic that fit their epidemiological situations, capacities, and values. Mass screening combined with control measures rapidly reduced the transmission of the SARS-CoV-2 infection. The COVID-19 pandemic has dramatically highlighted the essential role of diagnostics capacity in the control of communicable diseases. Mass screening has been increasingly used to detect suspected COVID-19 cases and their close contacts, asymptomatic case, patients attending fever clinics, high-risk populations, employees, even all population to identify infectious individuals. Mass screening is a key component to fight against SARS-CoV-2 and return to normalcy. Here we describe the history of mass screening, define the scope of mass screening, describe its application scenarios, and discuss the impact and challenges of using this approach to control COVID-19. We conclude that through a comprehension screening program and strong testing capabilities, mass screening could help us return to normalcy more quickly.

Keywords: SARS-CoV-2; close contacts; diagnostics capacity; mass screening.

Figure 1:

The flow diagram of screening. The targeted population were screened from the whole population. The first phase was “sieve”, which could test the positive population. The second phase was “sort”, which could diagnostic the positive population. This process removes some false positives. We can take the interventions to the targeted population.

Figure 2:

The diagnostic testing among persons was used to screened the patients of COVID-19. The screening could conduct from the incubation period to the symptomatic phase. At different phase, different measures were implemented.

Figure 3:

The schematic overview of sample pooling strategy of SARS-CoV-2 detection for mass screening. We can collect the nasopharyngeal swabs samples. Pooled testing of 5 and 10 samples pooled for SARS-CoV-2 virus was implemented when mass screening for population. A pool was considered positive if the viral gene was amplified, and individual samples within the pool were re-tested individually.

Figure 4:

Diagram of controlling the transmission of COVID-19 with mass screening and contact tracing. The mass screening is an intervention strategy for COVID-19 control in the general population. We can identify the isolate asymptomatic cases with SARS-CoV-2, isolate the cases, and trace the close contacts.