dr. dan brook shows us around the lab where researchers are racing to find a zika vaccine. >> this is where we do a variety of different anti-body tests. >> reporter: in 6 months they've made real progress. >> the vaccinat no detected virus. basically the vaccine was 100% effective in these animal models. >> reporter: transmitted by mosquito and sexual contact the zika virus is spreading rapidly through south america and the carribean. it's linked to a condition called microcephaly which causes severe birth defects. researchers are working in army research center in maryland. the team in maryland is developing a traditional vaccine similar to the flu shot. stitching dna from the zika virus to healthy dna. >> you can design exactly what pieces you want to put in the vaccine. >> reporter: for aroka the work he does in the lab is personal. he's from brazil and knows people cases of zika infection thousands of cases of microcephaly. developing a vaccine that help those people is important to me. >> reporter: who would get the vaccine? >> it would seem reasonable to me young healthy women. as we