Official Title
Defining the COVID-19 Immunity Denominator in the Mekong: a Cross-Sectional Seroprevalence Study of SARS-CoV-2 in Healthy Volunteers
Brief Summary

Background: In early 2020, many people thought Cambodia would have a serious COVID-19 outbreak due to the high number of Chinese travelers going to Cambodia. But as of June 14, 2020, only 128 cases of COVID-19 have been identified in the country. Many of these cases have been from people who had traveled in Europe. Researchers want to do antibody tests on blood from a sampling of people in Phnom Penh to learn the infection risks for people in the greater Phnom Penh area. Objective: To estimate the level of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the blood of people living in Phnom Penh, Cambodia. Eligibility: Healthy males and females age 18-65 living in Phnom Penh since January 2020. Design: A mobile unit will travel to schools, shopping areas, parks, and pagodas around Phnom Penh. Participants will be screened with questions about their age and where they live. They will have blood taken via fingerstick. About 80 uL of blood will be taken. It will be tested for SARS-CoV-2. This visit will take about 30 minutes. If the test result is positive, participants will be contacted by phone. They will be asked to have a second blood draw. This time, 20 mL of blood will be taken. They can have this visit at their home or in a clinic. This visit will take about 30 minutes. If a participant has an adverse event, the mobile units and at-home units will have the tools needed to aid the participant. If needed, the participant will be sent to a nearby clinic.

Detailed Description

This is a cross-sectional study performed annually over 3 years to procure blood samples by
fingerstick from healthy individuals living in the Phnom Penh area to evaluate seroprevalence
to SARS-CoV-2. A mobile unit will move between various markets, schools, hospitals, clinics,
parks, and other public places with local authority permissions. Participants with a positive
result on the screening SARS-CoV-2 ELISA will be contacted via telephone (since there is not
reliable mail in Cambodia) and invited to undergo an additional blood draw via venipuncture
during a home visit by the mobile team within 180 days of the initial sample collection. This
visit may also be conducted by CCDC/CNM/MOH study staff at a local clinic. Up to 10 of their
adult household contacts will be invited to enroll and screen at this time via fingerstick
for SARS-CoV-2 ELISA as part of an enriched sampling scheme to boost the probability of
identifying SARSCoV- 2 immune individuals; those with positive results will be invited to
undergo follow-up venipuncture as described above. Venipuncture samples will be used to study
the immune responses of Cambodians to the novel coronavirus.

Withdrawn
Healthy Volunteers
Eligibility Criteria

- INCLUSION CRITERIA:

In order to be eligible to participate in this study, an individual must meet all of the
following criteria:

1. Stated willingness to comply with all study procedures and availability for the
duration of the study.

2. Male or female, aged 18 - 65 years of age.

3. Residing in Phnom Penh since January 1, 2020.

4. Ability to provide consent.

EXCLUSION CRITERIA:

An individual who meets any of the following criteria will be excluded from participation
in this study:

1. Any acute illness requiring a visit to a clinic or hospital on the same day as study
enrollment.

2. Any underlying, chronic, or current medical condition that, in the opinion of the
investigator, would interfere with participation in the study (e.g., inability or
great difficulty in drawing blood).

Eligibility Gender
All
Eligibility Age
Minimum: 18 Years ~ Maximum: 65 Years
Countries
Cambodia
Locations

Cambodian Center for Communicable Disease (CCDC), Ministry of Health (MOH)
Phnom Penh, Cambodia

National Malaria Center (CNM), Ministry of Health (MOH)
Phnom Penh, Cambodia

Jessica E Manning, M.D., Principal Investigator
National Institute of Allergy and Infectious Diseases (NIAID)

National Institute of Allergy and Infectious Diseases (NIAID)
NCT Number
Keywords
Mobile Units
SARS-CoV-2 Immunoglobulin-Positive
Antibody-Based Tests
ELISA
Phnom Penh