On April 13, the Centers for Disease Control and Prevention (CDC) joined the World Health Organization (WHO) in confirming a link between Zika and the severe birth defect microcephaly. While officials at WHO also believe that there is enough evidence to conclude that the virus causes the autoimmune nervous disorder Guillain-Barré syndrome, the CDC is waiting for the results of additional studies.
Last year, the Zika virus—a mosquito-borne pathogen first identified in 1947 and never before seen in the Western Hemisphere—erupted in Brazil and has since spread to more than 20 countries in the Americas.
Eric Rubin, the Irene Heinz Given Professor of Immunology and Infectious Diseases at Harvard T.H. Chan School of Public Health, spoke recently about the outbreak with Madeline Drexler, editor of Harvard Public Health and author of the book “Emerging Epidemics: The Menace of New Infections.”
Zika, chikungunya, dengue, West Nile virus, Japanese encephalitis: All of these infections jumped to the Western Hemisphere in recent years from far-flung parts of the world and are now permanently established. What does that tell you?
That mosquitoes are a great way to spread disease. When you transplant a disease into a new area with the right mosquito vector, it can spread like wildfire. In the case of both chikungunya and Zika, it’s probably that people have no natural immunity and that both of those infections are being transmitted by the same mosquito—Aedes aegypti, which is extremely well-entrenched in these areas.