Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Oct;83(4):483-489.
doi: 10.1016/j.jinf.2021.07.037. Epub 2021 Aug 1.

Transmission of SARS-CoV-2 in the household setting: A prospective cohort study in children and adults in England

Elizabeth Miller  1 , Pauline A Waight  2 , Nick J Andrews  3 , Kelsey McOwat  4 , Kevin E Brown  5 , Katja Höschler  6 , Samreen Ijaz  7 , Louise Letley  8 , Donna Haskins  9 , Mary Sinnathamby  10 , Hannah Cuthbertson  11 , Bassam Hallis  12 , Vaishnavi Parimalanathan  13 , Simon de Lusignan  14 , Jamie Lopez-Bernal  15
Affiliations

Transmission of SARS-CoV-2 in the household setting: A prospective cohort study in children and adults in England

Elizabeth Miller et al. J Infect. 2021 Oct.

Abstract

Objectives: To measure secondary attack rates (SARs) in prospectively followed household contacts of paediatric and adult cases of SARS-CoV-2 infection in England.

Methods: Self-taken nasal swabs from household contacts of PCR confirmed cases of COVID-19 and blood samples on day 35 were tested for evidence of infection with SARS-CoV-2 virus.

Results: The secondary attack rate (SAR) among 431 contacts of 172 symptomatic index cases was 33% (95% confidence intervals [CI] 25-40) and was lower from primary cases without respiratory symptoms, 6% (CI 0-14) vs 37% (CI 29-45), p = 0.030. The SAR from index cases <11 years was 25% (CI 12-38). SARs ranged from 16% (4-28) in contacts <11 years old to 36% (CI 28-45) in contacts aged 19-54 years (p = 0.119). The proportion infected who developed symptoms (78%) was similar by age (p = 0.44) though <19 year olds had fewer mean number of symptoms than adults (p = 0.001) and fewer reported loss of sense of taste or smell (p = 0.0001).

Conclusions: There are high risks of transmission of SARS-CoV-2 virus in the home, including those where infection is introduced by a child. The risk of children acquiring infection was lower than that in adults and fewer developed typical symptoms of Covid-19 infection.

Keywords: Households; SARS-CoV-2 transmission; Secondary attack rates by age.

PubMed Disclaimer

Conflict of interest statement

Declaration of Competing Interest The authors have declared no competing interest. SdeL is the Director of the Royal College of General Practitioners Research and Surveillance, and hold a grant from AstraZeneca both funded through his university.

Figures

Fig. 1
Fig. 1
Flow diagram of study population and post-recruitment exclusions.
Fig. 2
Fig. 2
Serial intervals within households: days between symptom onset in index and contact.
See this image and copyright information in PMC

References

    1. World Health organisation. Household transmission investigation protocol for 2019-novel coronavirus (COVID-19) infection. 28 February 2020 Available at https://www.who.int/publications-detail/household-transmission-investiga...
    1. Madewell Z.J., Yang Y., Longini I.M., Jr, Halloran M.E., Dean N.E. Household transmission of SARS-CoV-2: a systematic review and meta-analysis. JAMA Netw Open. 2020;3(12) doi: 10.1001/jamanetworkopen.2020.31756. Dec 1e2031756PMID: 33315116; PMCID: PMC7737089. - DOI - PMC - PubMed
    1. Boddington N.L., Charlett A., Elgohari S., Walker J.L., McDonald H.I., Byers C. COVID-19 in great Britain: epidemiological and clinical characteristics of the first few hundred (FF100) cases: a descriptive case series and case control analysis. Bull World Health Organ. 2020 [Preprint] E-pub: 22 May http://dx.doi.org/10.2471/BLT.20.265603.
    1. de Lusignan S., Lopez Bernal J., Zambon M., Akinyemi O., Amirthalingam G., Andrews N. Emergence of a novel coronavirus (COVID-19): protocol for extending surveillance used by the royal college of general practitioners research and surveillance Centre and public health England. JMIR Public Health Surveill. 2020;6(2):e18606. doi: 10.2196/18606. - DOI - PMC - PubMed
    1. Guidance and standard operating procedure. COVID-19 virus testing in NHS laboratories https://www.england.nhs.uk/coronavirus/wp-content/uploads/sites/52/2020/...

Publication types