Inundating our popular and academic media circles is information regarding the Zika virus. A recent article by Farahnik et al in the Journal of the American Academy of Dermatology (2016;74:1286-1287) briefly outlines what is known about Zika infection thus far and its dermatologic manifestations. Pairing this article with Centers for Disease Control and Prevention guidelines on the topic, we are presented with an evolving introduction to this new entity. Here’s what we know:
- It is a single-stranded RNA arbovirus in the Flavivirus family transmitted by the bite of Aedes mosquitoes, with cases reported so far in Africa, Asia, and the Americas (particularly southern coastal and island destinations).
- It also is transmitted via transfusion of blood, sexual contact, and mother to fetus.
- There is theoretical risk for fetal microcephaly, intracranial calcifications, and other brain and eye abnormalities.
- Only 1 in 5 affected patients show any systemic manifestations of infection, including self-limited flulike symptoms and nonspecific exanthema, typically sparing acral sites and occurring within 1 to 2 weeks of virus exposure.
- Testing is recommended for pregnant women with possible Zika exposure (ie, travel to an area with active transmission of Zika virus, unprotected sex with a male with this travel history).
- Diagnosis can be made through state health departments, employing real-time reverse transcriptase–polymerase chain reaction (rRT-PCR) or enzyme-linked immunosorbent assay the week after symptom onset using serum, or rRT-PCR 2 weeks after symptom onset using urine. Further antibody testing can be done if a false-negative is suspected, but false-positives also are possible if a patient was exposed to or vaccinated against other flaviviruses (eg, dengue virus, West Nile virus, yellow fever virus)
- Testing is inaccurate if ordered within 7 days or more than 12 weeks following presumed exposure.
- If positive or inconclusive testing arises, serial fetal ultrasonography should be considered; if testing is negative, then a single fetal ultrasound is recommended to detect Zika abnormalities.
- Test results are automatically reported to respective state health departments.
- There is no treatment of this infection aside from supportive care.
What’s the issue?
As with any new outbreak, the applicability to the general population and true risks remain to be seen. Each of our clinics recalls the stark changes in patient intake and screening questions with infections as ubiquitous as methicillin-resistant Staphylococcus aureus to much rarer exposures such as Ebola virus, each with progressive understanding of risk groups, disease manifestations, and eradication and prevention measures.
By mid-June 2016, 30 hits on PubMed addressing Zika had already been cited just within the month, outlining various aspects of the infection, and many specialties, particularly neurology, obstetrics, primary care, infectious disease, and dermatology, are weighing in. Unfortunately, the majority of cases of primary Zika infection do not manifest with skin or systemic symptoms, and even cases that do are nonspecific, exanthematous, and flulike.
Vague as it may be so far, it is nonetheless imperative that clinicians be familiar with what is concretely known about Zika virus and acquaint ourselves with the travel distribution and restrictions, disease risk factors, known sequelae, testing availability and limitations, and reporting guidelines. From personal experience, as I traveled to Belize earlier this year during my first trimester of pregnancy before the travel restrictions were outlined, even obstetricians are not wholly familiar with the manner in which to order testing and the appropriate window to do so. I have been asymptomatic, my blood was drawn in a period of time that exceeded the interval for accurate results (as outlined above) and was therefore inappropriately recommended/ordered, and now serial fetal ultrasonography is being implemented every few weeks.
With lack of ubiquitous knowledge about the infection, clinicians are not universally certain of the appropriate next steps when a patient presents with Zika risk factors, and therefore anxiety remains high for pregnant patients and their contacts. The Centers for Disease Control and Prevention website is the official home base, and we should review it and await their further evolving specific recommendations as more cases unfortunately accumulate.
Have you encountered any patients this year with exposure to or symptoms of Zika infection, and what, if anything, have you outlined for them?