ArticleThe Lancet regional health. Europe2022
Household transmission of COVID-19 cases associated with SARS-CoV-2 delta variant (B.1.617.2): national case-control study.
Article in The Lancet regional health. Europe, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 128 papers, 3 of them syntheses that pooled it.
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Who cites it
128 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- SARS-CoV-2 variants of concern in children and adolescents with COVID-19: a systematic review.BMJ open · 2023Pooled it
- The role of children in household transmission of COVID-19: a systematic review and meta-analysis.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2022Pooled it
- One year on: What we have learned about the psychological effects of COVID-19 social restrictions: A meta-analysis.Current opinion in psychology · 2022Pooled it
- Quantitative analysis of massive SARS-CoV-2 testing in the community in France in 2021-2022 reveals the associations of variant, vaccination, and age with viral dynamics in symptomatic individuals.PLoS computational biology · 2026Article
- Daily profile of COVID-19 infections in Europe - a biophysical perspective.Biophysical reviews · 2025Review
- Disentangling the force of infection of SARS-CoV-2 in Dutch long-term care facilities.BMC public health · 2025Article
- Analysis of Variants' Dynamic Using the CLIMB Database in COVID-19 Patients Admitted to Hospitals of Barts Health NHS Trust.Journal of medical virology · 2025Article
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- Inferring effects of mutations on SARS-CoV-2 transmission from genomic surveillance data.Nature communications · 2025Article
- Article
- Article
- Bayesian modeling of the effect of vaccination and the delta and omicron variants on the COVID-19 epidemic in Burkina Faso using poisson log-linear autoregressive model.Frontiers in public health · 2025Article
- Comparative Analysis of COVID-19 Severity and Mortality Among Vaccinated and Unvaccinated Individuals During the Delta Variant Surge in a Tertiary Care Center: A Cohort Study.Health science reports · 2025Article
- Association between age of paediatric index cases and household SARS-CoV-2 transmission.Epidemiology and infection · 2024Article
- Household Transmission and Clinical Features of Respiratory Tract Infections That Were SARS-CoV-2 Positive and Negative.The Journal of infectious diseases · 2024Article
- Socioeconomic and Demographic Effects on SARS-CoV-2 Testing: Evidence From the State of Uttar Pradesh, India.Cureus · 2024Article
- Source of SARS-CoV-2 infection: results from a series of 584,846 cases in France from October 2020 to August 2022.BMC public health · 2024Article
- Review
- Representativeness of whole-genome sequencing approaches in England: the importance for understanding inequalities associated with SARS-CoV-2 infection.Epidemiology and infection · 2023Article
- Effects of public-health measures for zeroing out different SARS-CoV-2 variants.Nature communications · 2023Article
68 more citing papers are in PubMed but not listed here.
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16 authors.
Funding
Abstract
backgroundThe SARS-CoV-2 Delta variant (B.1.617.2), first detected in India, has rapidly become the dominant variant in England. Early reports suggest this variant has an increased growth rate suggesting increased transmissibility. This study indirectly assessed differences in transmissibility between the emergent Delta variant compared to the previously dominant Alpha variant (B.1.1.7).
methodsA matched case-control study was conducted to estimate the odds of household transmission (≥ 2 cases within 14 days) for Delta variant index cases compared with Alpha cases. Cases were derived from national surveillance data (March to June 2021). One-to-two matching was undertaken on geographical location of residence, time period of testing and property type, and a multivariable conditional logistic regression model was used for analysis.
findingsIn total 5,976 genomically sequenced index cases in household clusters were matched to 11,952 sporadic index cases (single case within a household). 43.3% (n=2,586) of cases in household clusters were confirmed Delta variant compared to 40.4% (n= 4,824) of sporadic cases. The odds ratio of household transmission was 1.70 among Delta variant cases (95% CI 1.48-1.95, p <0.001) compared to Alpha cases after adjusting for age, sex, ethnicity, index of multiple deprivation (IMD), number of household contacts and vaccination status of index case.
interpretationWe found evidence of increased household transmission of SARS-CoV-2 Delta variant, potentially explaining its success at displacing Alpha variant as the dominant strain in England. With the Delta variant now having been detected in many countries worldwide, the understanding of the transmissibility of this variant is important for informing infection prevention and control policies internationally.
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