Pooled testing for SARS-CoV-2, options for efficiency at scale

Abstract

Widescale testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is recognized as a key element of surveillance and outbreak control in the coronavirus disease 2019 (COVID-19) pandemic. The practical challenges, however, have often led to testing only symptomatic individuals and their close contacts. As many countries plan for a cautious relaxation of social restrictions, more effective approaches for widescale testing are increasingly important. Early in the COVID-19 pandemic, laboratories in several countries demonstrated the feasibility of detecting SARS-CoV-2 infection by pooled testing, which combines the specimens from several individuals. Since no further testing is needed for individuals in a negative pool, there is potential for greater efficiency of testing. Despite validations of the accuracy of the results and the efficiency in testing specific groups, the benefits of pooling are less acknowledged as a population surveillance strategy that can detect new disease outbreaks without posing restrictions on entire societies. Pooling specimens from natural clusters, such as school classes, sports teams, workplace colleagues and other social networks, would enable timely and cost-effective widescale testing for SARS-CoV-2. The initial result would be readily translatable into action in terms of quarantine and isolation policies. Clusters of uninfected individuals would be quickly identified and immediate local lockdown of positive clusters would be the appropriate and sufficient action while retesting those individuals. By adapting to the social networks of a population, pooled testing offers a cost-efficient surveillance system that is synchronized with quarantine policies that are rational, risk-based and equitable.

Pooling samples to increase testing capacity with Xpert Xpress SARS-CoV-2 during the Covid-19 pandemic in Lao People’s Democratic Republic

“…In addition to resources savings, the rapid turnaround time with pooled testing can have a significant impact in terms of quarantine and isolation policies. By rapidly identifying positive clusters, the health authorities can trigger lockdowns in areas with confirmed outbreaks and ease the restrictions where there is no active transmission [ 21 ].…”

SARS‐CoV‐2 infections in households in a peri‐urban community of Lima, Peru: A prospective cohort study

“…To increase the efficiency of RT‐PCR testing, we created separate pools of nasal and saliva samples combining sample aliquots (100 μl) collected on the same week from all members of the same household (pools sizes ranged from 2 to 12 samples). 8 NP samples were tested separately and on an individual basis (i.e., without pooling). All respiratory and saliva samples were tested for SARS‐CoV‐2 using RT‐PCR.…”

Ergebnisse von PCR-Pooltestungen an bayerischen Grund- und Förderschulen im Schuljahr 2021/2022 zur Surveillance im Präsenzunterricht während der SARS-CoV-2-Pandemie

“…Das Robert Koch-Institut empfahl zum Schuljahresanfang 2021/22 PCR-Pooltestungen als kostengünstige und zuverlässige Möglichkeit, SARS-CoV-2-Infektionen in Gruppen [17]…”

“…Das Robert Koch-Institut empfahl zum Schuljahresanfang 2021/22 PCR-Pooltestungen als kostengünstige und zuverlässige Möglichkeit, SARS-CoV-2-Infektionen in Gruppen 17 zeitnah nachzuweisen. Nordrhein-Westfalen führte als erstes Bundesland in Deutschland im Mai 2021 PCR-Pooltestungen mittels „Lolli-Methode“ flächendeckend an Grund- und Förderschulen ein 18 .…”