Relative infectiousness of asymptomatic SARS-CoV-2 infected persons compared with symptomatic individuals : a rapid scoping review

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OBJECTIVES: The aim of this study was to determine the relative infectiousness of asymptomatic SARS-CoV-2 infected persons compared with symptomatic individuals based on a scoping review of available literature.

DESIGN: Rapid scoping review of peer-reviewed literature from 1 January to 5 December 2020 using the LitCovid database and the Cochrane library.

SETTING: International studies on the infectiousness of individuals infected with SARS-CoV-2.

PARTICIPANTS: Studies were selected for inclusion if they defined asymptomatics as a separate cohort distinct from presymptomatics and if they provided a quantitative measure of the infectiousness of asymptomatics relative to symptomatics.

PRIMARY OUTCOME MEASURES: PCR result (PCR studies), the rate of infection (mathematical modelling studies) and secondary attack rate (contact tracing studies) - in each case from asymptomatic in comparison with symptomatic individuals.

RESULTS: There are only a limited number of published studies that report estimates of relative infectiousness of asymptomatic compared with symptomatic individuals. 12 studies were included after the screening process. Significant differences exist in the definition of infectiousness. PCR studies in general show no difference in shedding levels between symptomatic and asymptomatic individuals; however, the number of study subjects is generally limited. Two modelling studies estimate relative infectiousness to be 0.43 and 0.57, but both of these were more reflective of the infectiousness of undocumented rather than asymptomatic cases. The results from contact tracing studies include estimates of relative infectiousness of 0, but with insufficient evidence to conclude that it is significantly different from 1.

CONCLUSIONS: There is considerable heterogeneity in estimates of relative infectiousness highlighting the need for further investigation of this important parameter. It is not possible to provide any conclusive estimate of relative infectiousness, as the estimates from the reviewed studies varied between 0 and 1.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

BMJ open - 11(2021), 5 vom: 04. Mai, Seite e042354

Sprache:

Englisch

Beteiligte Personen:

McEvoy, David [VerfasserIn]
McAloon, Conor [VerfasserIn]
Collins, Aine [VerfasserIn]
Hunt, Kevin [VerfasserIn]
Butler, Francis [VerfasserIn]
Byrne, Andrew [VerfasserIn]
Casey-Bryars, Miriam [VerfasserIn]
Barber, Ann [VerfasserIn]
Griffin, John [VerfasserIn]
Lane, Elizabeth Ann [VerfasserIn]
Wall, Patrick [VerfasserIn]
More, Simon John [VerfasserIn]

Links:

Volltext

Themen:

COVID-19
Epidemiology
Infectious diseases
Journal Article
Review

Anmerkungen:

Date Completed 12.05.2021

Date Revised 02.04.2024

published: Electronic

Citation Status MEDLINE

doi:

10.1136/bmjopen-2020-042354

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM325006792