The first known case of Zika virus transmission in the U.S. has been reported in Texas by local health officials, who said it likely was contracted through sex and not a mosquito bite, according to Reuters.
The virus, linked to severe birth defects in approximately 35,000 babies in Brazil, is spreading rapidly in the Americas, and the World Health Organization (WHO) has declared an international public health emergency. The Zika virus was thought to be spread by the bite of mosquitoes of the Aedes genus, so sexual contact as a mode of transmission would be a potentially alarming development, according to Reuters.
“The patient was infected with the virus after having sexual contact with an ill individual who returned from a country where Zika virus is present” this year, a Dallas County statement read. The county subsequently tweeted that the virus was contracted from someone who had traveled to Venezuela, and that a second case of Zika imported from Venezuela has also been documented.
After this case, the Centers for Disease Control and Prevention (CDC) advised men to consider using condoms after traveling to areas with the Zika virus. Pregnant women should avoid contact with semen from men exposed to the virus.
Previously, international health officials noted one U.S. case of possible person-to-person sexual transmission, but the Pan American Health Organization said more evidence was needed to confirm sexual contact as a means of Zika transmission. The medical literature also has one case in which the virus was detected in semen.
So far, the virus has been reported in more than 30 countries.
In related news, Pfizer, Johnson & Johnson, and Merck have announced that they are evaluating their technologies and existing vaccines for their potential to combat the Zika virus. Several drug developers and universities are attempting to produce a vaccine for Zika, but experts have said that producing a safe and effective vaccine will take time.
“Pfizer is currently analyzing its existing vaccines portfolio in response to the Zika outbreak to see where we might be able to play a role,” a company spokeswoman told Reuters.
Japan’s Takeda Pharmaceutical Co. Ltd. said it has created a team to investigate how it might help make a vaccine, shortly after Sanofi announced it would launch a Zika vaccine program.
Merck, which helped develop the first successful Ebola vaccine, said it was working with public health partners to see how its expertise could be useful.