All three viruses that cause these diseases are transmitted by mosquitoes. Dengue is present throughout the hemisphere, and chikungunya has sickened over 1.5 million people in the Region. Now Zika is presenting yet another challenge for countries of the Americas.

Buenos Aires, 6 November 2015 (PAHO/WHO) — Health authorities, epidemiology experts from Latin America and the Caribbean, and representatives of World Health Organization (WHO) Collaborating Centers gathered in Buenos Aires, Argentina, this week to discuss actions to improve countries' preparedness and response with respect to dengue, chikungunya and Zika, three mosquito-transmitted viruses. The meeting was organized by the Ministry of Health of Argentina and the Pan American Health Organization (PAHO), which serves as WHO's Regional Office for the Americas.