The Partnership for Research on Ebola Virus in Liberia (PREVAIL) recently conducted a clinical research study where Ebola survivors and their close contacts benefited from cataract removal surgeries. The study, called PREVAIL 7, sought to address the issues of safety for participants to undergo cataract surgery and to define the post-surgical care needed to achieve the best visual outcomes.
People with cataracts have difficulty seeing because the lens of the eye, which reflects light and allows them to see clearly, has become cloudy. Cataracts are the leading cause of reversible blindness in the world, and surgery is the only known effective cure.
The study, which is still following up the participants, has two major goals: (1) to determine the proportion of EVD survivors with viral persistence in ocular (eye) tissues, and (2) to compare the amount of inflammation between survivors and control patients at one month and three months after cataract surgery.
In addition, the investigators aim to assess whether the visual outcomes in Ebola survivors differ from those in other patients, whether age and gender play a role in their outcomes, and whether structural changes in the eye from Ebola infection impact these outcomes.
For the study, PREVAIL enrolled 24 Ebola survivors whose blood tested positive for the presence of EVD antibodies and 10 close contacts whose blood showed no evidence of EVD exposure.
Participants in the study were drawn from the PREVAIL eye care sub-studies under the Ebola Natural History Study known as PREVAIL 3 and were over 14 years old – only one eye of a survivor could be a candidate for the surgery. Pregnant women were excluded.
The research is a joint collaboration of multiple organizations spanning academic, government, faith-based, private, and non-governmental organizations from four countries.
These organizations included the U.S. National Institutes of Health, Johns Hopkins University, Emory University, LVPrasad/the Liberian Eye Center at JFK Hospital under Dr. Kumar Nishant, New Sight Eye Center under Robert Dolo, ELWA Hospital, Samaritan’s Purse, John Snow Inc., and the Liberian Ministry of Health.
Two U.S.-based surgeons, Dr. Daniel Gradin and Dr. Benjamin Roberts, donated one week of their time to Samaritan’s Purse to perform the surgeries. They were chosen because of their rigorous training and extensive experience in Kenya and South Sudan performing similar cataract surgeries.
At ELWA Hospital, under the direction of Dr. John Fankhauser, they deployed the innovative Baylor Smart Pod—a small field clinic—for testing the aqueous fluid of the eye in Ebola virus.
This pod provided clinical safety for participants, staff, and surgeons. Since June 2015, the PREVAIL 3 Natural History Eye Sub-Study has enrolled about 2,100 Ebola survivors and close contacts and followed them prospectively to shed light on the ocular complications of EVD.