Officials in Texas have reported the first case of Zika virus contracted in the United States, saying it was sexually transmitted. If confirmed, it marks only the second known case of Zika transmission through sexual contact. Zika has continued to spread rapidly across Latin America, with Chile reporting its first three cases. The mosquito-borne illness, while generally not life-threatening, has been linked to the birth defect microcephaly, which causes babies to be born with abnormally small heads. The link has raised debates over restrictive abortion laws in countries like Brazil, which has seen nearly 3,700 suspected cases of microcephaly. The World Health Organization’s Anthony Costello announced the latest steps against Zika.

Dr. Anthony Costello: “This morning we’ve now set up a global response unit, which brings together all people across WHO in headquarters in the regions to deal with a formal response, using all the lessons we’ve learned from the Ebola crisis.”

Scientists have linked rising temperatures from global warming to the increased incidence of mosquito-borne infections such as Zika.