The Centers for Disease Control and Prevention said Tuesday that it is investigating 14 new reports of potential sexual transmission of the Zika virus in the United States. Several of the cases involve pregnant women.
In at least two of the cases, a Zika infection was confirmed in women whose only known risk factor was sexual contact with an ill male partner who recently had returned from one of the nearly three dozen countries where the virus has now spread.
Four other women have tested positive for Zika in preliminary lab tests but are awaiting final confirmation. The CDC said eight other cases remain under investigation.
Officials said the same scenario played out in most, if not all, of the suspected cases: A man who had traveled to a Zika-affected area returned to the United States and had sex with a female partner, who soon began to display symptoms consistent with Zika.
The agency did not identify the states where these cases are being investigated.
Scientists still believe that mosquitoes are the main means of transmission for the virus, which has spread explosively throughout the Americas in recent months and is suspected of being linked to serious birth defects and a rare autoimmune disease. Prior to February, only one case of sexual transmission had been documented.
