Dr. Ian Crozier’s blood was free of Ebola when he was discharged from Emory University Hospital in October 2014 after a dangerous struggle with the virus. So it came as a surprise when two months later, the sharp eye pains and failing vision that he had been experiencing was found to be due to Ebola in his left eye. Eventually, the virus turned his eye color from blue to green.
This latest development in the fight against Ebola comes as a peculiar instance of what many call “post-Ebola syndrome.” According to the New York Times, former patients experience lingering effects from the disease, including muscle and joint aches, fatigue, and hearing loss. However, eye color changes are rare and most commonly occur from the herpes virus. It’s alarming to see this in Ebola survivors, because now blindness is yet another post-Ebola problem for already overwhelmed doctors to treat.
Dr. Crozier contracted the virus while working as a World Health Organization (WHO) volunteer in a Sierra Leone Ebola treatment ward last year. On Sept. 9, he was airlifted to Emory University hospital, where he spent 40 days on a ventilator and dialysis. In less than two months after his release in October, he returned to the hospital with severe pain, pressure, and fading vision in his left eye. Initially, doctors thought this was uveitis, an eye inflammation that can lead to blindness. However, by using a hair-thin needle, ophthalmologist Dr. Steven Yeh extracted fluid from inside Crozier’s eye, and it tested positive for Ebola.
Fortunately, the disease is not transmissible through tears or surface contact with the eye, so casual exposure poses no risk. However, it is a greater danger to eye surgeons operating on Ebola patients. But after an unsuccessful steroidal treatment, Crozier’s eye finally saw improvement with an experimental antiviral pill.
The reason behind the virus’ continued replication in the eye is probably due to the biology of immune privilege. According to NPR, the eye is walled off from the immune system (to prevent immune overreactions in the eye). Unfortunately, this immune “privilege” causes the immune system to overlook pathogens, like the ebolavirus, in the eye. Thus, Ebola survivors can be cleared of the disease and yet still harbor it in these immune-privileged organs. (The male testes are another, so the virus remains transmissible through semen for months after recovery.)
However, the phenomenon that changed Dr. Crozier’s eye color from blue to green is not completely clear. Dr. C. Stephen Foster, a Harvard clinical professor of ophthalmology, first thought it was the virus killing pigmented cells in the iris. Upon further examination, he concluded that the homogeneity of the green is due to some metabolic alteration that produced a chemical responsible for the color change. What might have prompted that change remains under further study.
The implications of this finding are disturbing. In addition to the difficulty of treating and containing Ebola in West Africa (the CDC emphasizes Liberia, Sierra Leone, and Guinea), those who are lucky enough to survive (roughly only 30 percent, depending on the strain) also suffer debilitating symptoms after their recovery. This is what has made Ebola a source of ongoing fear and death; WHO reports that the death rate is anywhere between 25 percent and 90 percent, based on statistics from past outbreaks.
The question now arises: how could the disease re-enter the bloodstream in a drug-resistant form and continue to be contagious? The urgency of this persistent problem is even more immediate: hospital and living conditions must improve, preventive and post-Ebola information dissemination throughout the most threatened communities is even more crucial, and the medical task force must strengthen in numbers and capacity.
Despite these daunting prospects, there is some good news. The CDC reported on May 9, 2015, that Liberia’s country classification has been changed to a “country with former widespread transmission but current, effective control measures.” This is because 42 days (two incubation periods for Ebola) have passed since the last Ebola victim was buried. Still, it goes without saying that we have a long way to go in the fight against Ebola.