Zika virus distribution as of January 15, 2016WIKIMEDIA, CDCViral immunologist Eva Harris has been tracking dengue virus infections in Nicaragua for more than two decades. During the last nine months, her lab has taken on more than 40 new projects, all related to Zika virus. Many of these latest studies take advantage of blood samples donated as parts of various dengue surveillance projects, including one cohort of 3,500 Nicaraguan children who have given blood annually for several years. This cohort and others like it are providing researchers with an inside look at of how Zika spreads in a naive population, and how it interacts with dengue. “We can now analyze Zika infections in children who we know have had a previous dengue infection or not,” said Harris, a professor of infectious diseases and vaccinology at the University of California, Berkeley School of Public Health.
Examining existing cohorts, researchers hope to answer basic questions about the epidemiology of this emerging virus. For one, have certain populations acquired herd immunity as a result of previous exposure to Zika?
“Is it true that there hasn’t been Zika around the world?” asked Isabel Rodriguez-Barraquer, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore. “Or has it been there, but we haven’t found it?”
Rodriguez-Barraquer and colleagues are looking for antibodies against Zika in 10,000 blood samples from ongoing dengue studies in Colombia, Thailand, India, and parts of Africa. The US National Institutes of Health (NIH) and the Thai Armed Forces Research Institute of Medical Sciences, meanwhile, will add retrospective and prospective Zika surveillance to existing dengue cohort studies in ...
