Dataset Information

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

ABSTRACT:

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.

SUBMITTER: McEvoy D

PROVIDER: S-EPMC8098293 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

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

McEvoy David D McAloon Conor C Collins Aine A Hunt Kevin K Butler Francis F Byrne Andrew A Casey-Bryars Miriam M Barber Ann A Griffin John J Lane Elizabeth Ann EA Wall Patrick P More Simon John SJ

BMJ open 20210504 5

<h4>Objectives</h4>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.<h4>Design</h4>Rapid scoping review of peer-reviewed literature from 1 January to 5 December 2020 using the LitCovid database and the Cochrane library.<h4>Setting</h4>International studies on the infectiousness of individuals infected with SARS-CoV-2.<h4>Participants</h4>Studies we ...[more]

PMID: 33947725

Similar Datasets

Project description:BackgroundPlasmodium falciparum (P. falciparum) remains a significant public health challenge globally, especially in sub-Saharan Africa (SSA), where it accounts for 99% of all malaria infections. The outcomes of P. falciparum infection vary, ranging from asymptomatic to severe, and are associated with factors such as host immunity, parasite genetic diversity, and multiplicity of infection (MOI). Using seven neutral microsatellite markers, the current study investigated P. falciparum genetic diversity and MOI in both asymptomatic and symptomatic malaria individuals in Uganda.MethodsThis cross-sectional study analyzed 225 P. falciparum isolates from both asymptomatic and symptomatic malaria patients, ranging in age from 6 months to ≥ 18 years. P. falciparum genetic diversity, MOI, and multi-locus linkage disequilibrium (LD) were assessed through genotyping of seven neutral microsatellite markers: Poly-α, TA1, TA109, PfPK2, 2490, C2M34-313, and C3M69-383. Genetic data analysis was performed using appropriate genetic analysis software.ResultsP. falciparum infections exhibited high genetic diversity in both asymptomatic and symptomatic individuals. The mean expected heterozygosity (He) ranged from 0.79 in symptomatic uncomplicated malaria cases to 0.81 in asymptomatic individuals. There was no significant difference (p = 0.33) in MOI between individuals with asymptomatic and symptomatic infections, with the mean MOI ranging from 1.92 in symptomatic complicated cases to 2.10 in asymptomatic individuals. Polyclonal infections were prevalent, varying from 58.5% in symptomatic complicated malaria to 63% in symptomatic uncomplicated malaria cases. A significant linkage disequilibrium (LD) was observed between asymptomatic and symptomatic uncomplicated/complicated infections (p < 0.01). Genetic differentiation was low, with FST values ranging from 0.0034 to 0.0105 among P. falciparum parasite populations in asymptomatic and symptomatic uncomplicated/complicated infections.ConclusionThere is a high level of P. falciparum genetic diversity and MOI among both symptomatic and asymptomatic individuals in Uganda. Asymptomatic carriers harbor a diverse range of parasites, which poses challenges for malaria control and necessitates targeted interventions to develop effective strategies.

Dataset Information

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

Objectives

Design

Setting

Participants

Primary outcome measures

Results

Conclusions

Publications

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

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets