The Partnership for Research on Ebola Vaccines in Liberia (PREVAIL), a Liberia-US research team, plans to launch a natural history study of Ebola survivors for better understanding of the after-effects of the Ebola virus disease.

According to a PREVAIL statement, four sites in Monrovia and locations in the US may begin enrollment for this study in the coming months, Xinhua news agency reported.

The study is pending regulatory review and approval, according to the statement issued by the National Institute of Allergy and Infectious Diseases (NIAID), part of the US National Institutes of Health (NIH).

NIAID conducts and supports research at NIH, throughout the US and worldwide.

It carries out studies of the causes of infectious and immune-mediated diseases, and develops better means of preventing, diagnosing and treating these illnesses.

PREVAIL is currently conducting trials of two experimental Ebola vaccines in Liberia with more than 600 people in Liberia participating in the first stage and about 1,500 volunteers expected to enroll in the second phase.

The trial, which began on February 2, 2015, in Monrovia, is testing the safety and efficacy of the cAd3-EBOZ candidate vaccine co-developed by NIAID scientists and GlaxoSmithKline, and the VSV-ZEBOV candidate vaccine developed by the Public Health Agency of Canada and licensed to NewLink Genetics Corporation and Merck.