Prevention measures (specifically, vector control) are a current priority, pending advances in diagnostics; the World Health Organization and the Pan American Health Organization have issued recommendations (online Technical Appendix reference 44). In the United States, multiple factors guard against the explosive epidemic occurring throughout Central and South America. Specifically, lower rates of human crowding in urban areas, wider access to air conditioning and mosquito repellants, and waste management limit mosquitoborne transmission, which has been the case for DENV (online Technical Appendix reference 71). Nonetheless, further entomologic research is needed to define the range of Zika virus vectors and identify new areas where autochthonous transmission could take place to enable early intervention. Investment is also needed in durable control measures such as adaptable vaccine platforms for arboviruses; currently, no Zika virus vaccines are in advanced development (9).