Jackeline, 26, holds her son who is 4-months old and born with microcephaly, in front of their house in Olinda, near Recife, Brazil. Zika is a disease that seems to keep evolving, and escalating. The mosquito-borne virus many thought would be a milder version of dengue has turned out to be a serious neurological threat, causing the birth defect microcephaly (which often includes brain damage). Recent laboratory analyses identified Zika virus infections in three people who died in Brazil last year, the health ministry said, although authorities could not confirm that Zika alone was responsible for their deaths.