(REUTERS HEALTH)   Global health officials are racing to better understand the Zika virus behind a major outbreak that began in Brazil last year and has spread to many countries in the Americas. The following are some questions and answers about the virus and current outbreak: How do people become infected? Zika is transmitted to people through the bite of infected female mosquitoes, primarily the Aedes aegypti mosquito, the same type that spreads dengue, chikungunya […]