Cases of the Zika virus continue to grow, with health departments reporting at least 19 people diagnosed in the U.S. and 19 people infected in Puerto Rico.
The U.S. cases -- in at least 8 states -- have all been travelers who returned from a country where the transmission of Zika virus from mosquitoes to humans is ongoing.
The state with the highest number of cases is Hawaii, where six people have been found to have the disease. One infant in Hawaii was born earlier this month with microcephaly, which has been associated with the virus. The baby's mother had shown evidence that she had the virus while traveling in Brazil.
In Illinois, two pregnant women were diagnosed with the disease and officials said they had contracted the virus in Honduras and Haiti. In Florida three people have been diagnosed with the disease.
Health officials had already found that the Zika virus was being transmitted between mosquitoes and people in Puerto Rico, where the 19 cases were found. It was not clear how many of the cases came from travel.
The U.S. Centers for Disease Control and Prevention is warning pregnant women to reconsider traveling to the 24 known countries and territories where the Zika virus is being transmitted. The virus is associated with a dangerous birth defect called microcephaly, which results in an underdeveloped brain and head. CDC health officials are also investigating if the virus is linked to an increase in a rare immunological syndrome called Guillain-Barre, which can lead to paralysis.
In Brazil the military has been called in to help hundreds of thousands of health officials and other government workers stop the virus from spreading. The country first sounded the alarm about microcephaly being associated with the virus after thousands of infants were born with malformed heads.
In El Salvador the health ministry took the dramatic step of asking all women to not get pregnant for two years until the virus can be under control.
The common symptoms of the Zika virus include fever, rash, joint pain and conjunctivitis, according to the CDC. Approximately one in five people infected with the virus shows symptoms. Severe complications from the virus that require hospitalization are rare and most people are over the worst of the symptoms after a week, according to the CDC.