Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016

We conducted a case-control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors.A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging.Snellen visual acuity was <6/7.5 in 75.6% (97.5% CI 63%-85.7%) of EVD survivors and 75.5% (97.5% CI 59.1%-87.9%) of controls.Unilateral white cataracts were present in 7.4% (97.5% CI 2.4%-16.7%) of EVD survivors and no controls.Aqueous humor from 2 EVD survivors with cataract but no anterior chamber inflammation were PCRnegative for Zaire Ebola virus, permitting cataract surgery.A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%-25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry. T he most recent Ebola virus disease (EVD) outbreakin West Africa is the largest outbreak in history.As of March 27, 2016, an estimated 3,956 persons in Sierra Leone had died from EVD, and 10,168 had survived (1).The scale of this epidemic has enabled the study of large numbers of survivors, facilitating the characterization of post-Ebola syndrome.Ocular symptoms have been reported, with incidence among survivors ranging from 14% to 60% (2-4).Evidence of acute uveitis on ophthalmic examination ranges from 18% to 58% (4-7).Classification of uveitis also varies and has been reported as 36%-62% anterior, 3% intermediate, 26%-36% posterior, and 18%-25% panuveitis (4,8).However, little is known regarding the medium-to long-term visual outcome of survivors or the rates of background uveitis and chorioretinal lesions within the local population.Two published cases (9-11) and 2 case series (7,12) included fundus imaging, which attribute a range of retinal lesions to Ebola uveitis.Fourteen weeks after EVD discharge, a unilateral anterior hypertensive uveitis developed in 1 survivor and soon progressed into an aggressive anterior scleritis and intermediate uveitis.Viable Zaire Ebola virus (EBOV) was detected from the aqueous humor 9 weeks after the clearance of viremia ( 9).The duration of EBOV ocular persistence remains unknown, although repeated aqueous humor testing in the same survivor was negative for EBOV by quantitative reverse transcription PCR (qRT-PCR) 1 year later (10).Recurrences up to 13 months after EVD discharge have been reported, but confirmation of Ebola etiology through aqueous humor analysis was not conducted (7).Because of the unknown prevalence and duration of EBOV persistence in aqueous humor, survivors' access to cataract surgery is still restricted.Our study aimed to detect if any specific retinal signs can be attributed to past EVD in survivors, to describe the implications for visual acuity, and to assess for EBOV persistence in survivors with cataracts amenable to cataract surgery where no intraocular inflammation was present. Methods Study DesignWe conducted a case-control prospective study comparing ophthalmic findings between EVD survivors and a control group during January-June 2016.Reporting of the findings is in accordance with guidelines set forth in the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement (13). Study PopulationWe searched a database of EVD survivors from the 2014-2016 EVD epidemic who had attended the EVD survivors clinic at 34th Regiment Military Hospital in Freetown, Sierra Leone, for patients who had reported ophthalmic complaints at any of their follow-up appointments (2).