Health officials are alarmed at the rapid spread of Zika virus in Latin America and the Caribbean. Brazil reported its first case of the mosquito-borne virus last year. Since then, cases have been reported in 21 countries and territories throughout the region. Disease experts suspect the virus of causing an unusual spike of a rare birth defect. It may also be linked to a syndrome that can lead to paralysis. The Centers for Disease Control is advising pregnant women to avoid travel to countries where the virus is spreading. Guest host Indira Lakshmanan and a panel of guests discuss efforts to control the virus and develop a vaccine.