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.
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.
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
Margaret Pendzich
Durham, North Carolina, United States
Dana Pasquale, PhD, Principal Investigator
Duke University