The authors also suggest that ophthalmic screening of all babies born in epidemic areas may not be necessary at this time.
Drs. Lee M. Jampol and Debra A. Goldstein from the Department of Ophthalmology at Northwestern University's Feinberg School of Medicine in Chicago recently published an invited commentary in the Journal of the American Medical Association Ophthalmology pertaining to a study on the ophthalmologic manifestations of congenital Zika virus infection.
The study itself is timely, as the Zika virus outbreak that began in Brazil has now spread widely throughout the Americas and is receiving a great deal of attention from medical communities, governmental entities, and the global media. At this time, no vaccine against the Zika virus has been developed, prompting a recommendation for women in regions associated with the epidemic to avoid becoming pregnant. Additionally, women that are already pregnant are being advised to avoid these regions.
To place the study in context, Jampol and Goldstein describe what is well-known to most - the world is getting smaller. They speak to this simple concept using more elegant language by stating, "Human and insect travel between continents has resulted in the dissemination of previously remote infections to more populated parts of the world." Additionally, they remind us that this is by no means the first occurrence of such a phenomenon by describing the movement of a related virus, the West Nile virus, from Israel to New York, and its spread across the country, which was accompanied by neurologic disease and retinal lesions.
In pregnant women, infection with Zika virus during the first or second trimester is thought to be the cause of microcephaly, as well as potential other conditions. The virus itself is carried and transmitted by a particular type of mosquito, Aedes aegypti. In non-pregnant individuals, Zika virus infection can cause a temporary fever, a nonspecific rash, and joint pain. In some infected individuals, no symptoms are present. Regardless of symptomatology, Zika virus infection is not considered to be life-threatening.
Ophthalmologic manifestations of congenital Zika virus infection are recent. The commentary authors note that very little data regarding the ophthalmologic manifestations of congenital Zika virus infection are available. The authors succinctly describe the results of one small, recently reported study by stating that the study, "described 3 babies from Brazil with microcephaly and presumed Zika virus intrauterine infection who had macular pigment mottling and loss of foveal reflex, with 1 manifesting well-defined macular atrophy."
Jampol and Goldstein explain that the results of the report by de Paula Freitas et al implicated Zika virus infection, "...as the cause of chorioretinal scarring and possibly other ocular abnormalities in infants with microcephaly recently born in Brazil." Their conclusion was based on the study of 29 Brazilian microcephalic babies with a presumed diagnosis of congenital Zika virus infection, 10 of whom (35%) had ocular abnormalities. These abnormalities were described as lesions that, "included posterior pole pigmentary clumping and areas of sharply circumscribed chorioretinal atrophy." Importantly, just under 80% of the mothers of these microcephalic babies reported having symptoms consistent with Zika virus infection, and the majority of the symptoms occurred in the first trimester of their pregnancies.
Jampol and Goldstein provide what would seem to be a very reasonable recommendation based on the findings of the study: "Based on current information, in our opinion, clinicians in areas where Zika virus is present should perform ophthalmologic examinations on all microcephalic babies." The authors also suggest that ophthalmic screening of all babies born in epidemic areas may not be necessary at this time, as it remains unclear as to whether these eye lesions would be observed in babies that are not microcephalic.
William Perlman, PhD, CMPP is a former research scientist currently working as a medical/scientific content development specialist. He earned his BA in Psychology from Johns Hopkins University, his PhD in Neuroscience at UCLA, and completed three years of postdoctoral fellowship in the Neuropathology Section of the Clinical Brain Disorders Branch of the National Institute of Mental Health.