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Network-Targeted Strategies for Efficient Community SARS-CoV-2 (COVID-19) Sampling

Network-Targeted Strategies for Efficient Community SARS-CoV-2 (COVID-19) Sampling

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04437706
Acronym
Snowball
Enrollment
602
Registered
2020-06-18
Start date
2020-12-11
Completion date
2022-07-25
Last updated
2024-06-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

COVID-19, SARS-CoV 2

Keywords

network analysis, contact tracing, respondent driven sampling

Brief summary

The primary objective is to use network targeted sampling design to detect active and/or undiagnosed cases of COVID-19 in the community and determine the spread or distribution of 1) active infection, and 2) past exposure. The hypothesis is that there are many undiagnosed and/or asymptomatic people in the community who may be unknowingly spreading the virus or have been exposed and have antibodies. We propose to implement respondent-driven sampling (RDS) which leverages effort on the part of seed or index cases to recruit contacts for participation.

Detailed description

Purpose and objective: The purpose of this study is to use community sampling to detect active, undiagnosed COVID-19 cases and/or determine the spread or distribution of active infection. The objective is to use a network targeted sampling design to direct testing to yield a higher proportion of results which indicate active infection and possibly differentiating between venues or communities where transmission is active and undiagnosed. Study activities: A person who tests positive for COVID-19 will be given a set of tokens to give to contacts that will entitle these contacts to make an appointment to receive a test for COVID-19. Population groups: The population group will include people with index cases of COVID-19 and their contacts for the past 14 days. As these contacts are tested and receive positive results, they will be given tokens to hand out to their contacts over the past 14 days. The network of positive cases will blossom to reveal community transmission and asymptomatic cases, thus giving researchers an indication of disease prevalence. Data analysis: At the completion of each epoch and at the end of the study, we will scale the social networks up and conduct network analysis using SAS and the igraph package in R. These analyses will be applied in an ongoing manner to guide selection of seeds in subsequent epochs to ensure representativeness and to guide selection of alters to encourage longer referral chain lengths. Risk/safety issues: The primary risks include discomfort from the nasal swab and risks from the venous blood draw used in testing and the potential loss of confidentiality. All efforts will be made to securely manage the data to ensure participant confidentiality.

Interventions

None listed

Sponsors

Duke University
Lead SponsorOTHER

Study design

Observational model
ECOLOGIC_OR_COMMUNITY
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Positive COVID-19 test result -or- receipt of a coupon from a previous study participant * Resident of Durham County (for seed participant only) * Willing to undergo COVID-19 test nasopharyngeal swab for RT-PCR testing and blood draw for COVID-19 antibody testing * Age 18+ * Speak and understand English

Exclusion criteria

* Currently receiving inpatient treatment for COVID-19 * Unable to consent

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants with Active Infection12 monthsNumber of participants with active COVID-19 infection
Number of Participants with Antibodies Indicating Past Exposure12 monthsNumber of participants with antibodies indicating past exposure to SARS-CoV-2

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026