Microcephaly, a birth defect which causes babies to be born with unusually small heads and brains, is linked to the Zika virus. (Photo by Ueslei Marcelino/Reuters) Costa Rica’s Ministry of Health is planning to use bacteria in the fight against the Aedes aegypti mosquito, which spreads Zika virus, dengue, and chikungunya, amongst other viruses and diseases.   The bacterium, known as...