A large study recently began in Liberia, West Africa to examine how genes affect a person’s response to the Ebola virus. The study is enrolling approximately 8,000 adults and children and includes people who got sick with Ebola and survived, people who were close contacts of Ebola patients but never became infected, and people who have no known Ebola exposure. Stored blood samples from up to 500 people who died from Ebola will also be included in the study.
After completing a rigorous informed consent process, participants will provide their medical history and a blood sample. The blood samples will be sent to labs in Liberia and in the U.S., where investigators will use specialized equipment to read each participant’s DNA. They will be examining whether certain genes are associated with a higher risk of contracting Ebola virus disease (EVD) or of dying from Ebola infection. They also hope to determine if genes influence the problems some EVD survivors continue to have after recovery, such as uveitis (eye inflammation), or traces of virus lingering in bodily fluids, including semen.
A team of scientists from NIAID, the Broad Institute of MIT and Harvard in Boston, and a U.S.-Liberia clinical research collaboration known as the Partnership for Research on Ebola Virus in Liberia (PREVAIL), are conducting the research. NIAID and the Ministry of Health in Liberia are co-sponsors of PREVAIL and the study. Co-principal investigators include Lisa Hensley, Ph.D., deputy director of NIAID’s Integrated Research Facility in Frederick, Maryland; Mosoka Fallah, Ph.D., M.P.H., deputy director general of the National Public Health Institute of Liberia; and Pardis Sabeti, M.D., D.Phil., leader of the infectious disease program at the Broad Institute.
Participants will include Ebola survivors and their household contacts already enrolled in a PREVAIL-led Ebola natural history study. Some of these household contacts had antibody evidence of Ebola virus exposure despite having no obvious signs of disease. Why some infections are asymptomatic while others are fatal, or why some people rapidly clear the infection while others remain in treatment for weeks or have lingering traces of virus months or years after infection, remains unclear. Investigators predict that by studying people’s DNA, they might uncover genetic differences that influence these outcomes.