Quarantine and serial testing for variants of SARS-CoV-2 with benefits of vaccination and boosting on consequent control of COVID-19

Abstract

Quarantine and serial testing strategies for a disease depend principally on its incubation period and infectiousness profile. In the context of COVID-19, these primary public health tools must be modulated with successive SARS CoV-2 variants of concern that dominate transmission. Our analysis shows that 1) vaccination status of an individual makes little difference to the determination of the appropriate quarantine duration of an infected case, whereas vaccination coverage of the population can have a substantial effect on this duration, 2) successive variants can challenge disease control efforts by their earlier and increased transmission in the disease time course relative to prior variants, and 3) sufficient vaccine boosting of a population substantially aids the suppression of local transmission through frequent serial testing. For instance, with Omicron, increasing immunity through vaccination and boosters—for instance with 100% of the population is fully immunized and at least 24% having received a third dose—can reduce quarantine durations by up to two days, as well as substantially aid in the repression of outbreaks through serial testing. Our analysis highlights the paramount importance of maintaining high population immunity, preferably by booster uptake, and the role of quarantine and testing to control the spread of SARS CoV-2.

Long-term vaccination strategies to mitigate the impact of SARS-CoV-2 transmission: A modelling study

“…Our analyses illustrate the importance of continued booster doses as part of the wider public health response to ongoing endemic transmission of SARS-CoV-2 [ 23 , 60 ]. Prioritising boosters to high-risk and older populations is an efficient strategy in terms of reducing hospitalisations and death, while managing finite healthcare resources, but further data are required to understand the cost-effectiveness of vaccinating a wider age group to protect against the consequences of long COVID.…”

Modelling the impact of timelines of testing and isolation on disease control

“…One of the key measures that have been widely used during COVID-19 is testing to identify infected cases and isolate them to reduce onward transmission ( CDC, 2022b ; Grassly et al, 2020 ; MacIntyre, 2020 ; Mercer & Salit, 2021 ; Wells et al, 2021 ). Prior to the widespread availability of RA tests, RT-PCR was the predominant approach to identifying SARS-CoV-2 infections ( Rosenberg & Holtgrave, 2021 ; Wells et al, 2021 , 2022b , a ). However, RT-PCR requires laboratory assay, a process that often delays the test results after sample collection, which could lead to a late start of isolation ( Rosenberg & Holtgrave, 2021 ).…”