While health officials continue looking for a cure for the Zika virus, scientists are considering the possibility that the mosquito-borne illness could also be sexually transmitted from human to human.

Citing a case in France, scientists raised concerns in a letter to the New England Journal of Medicine on Friday that the virus could be transmitted via oral sex.

While it’s widely understood that the virus is spread primarily though mosquitos, the presence of the infection in 10 countries where no infected mosquitos have been found suggests there’s more to the transmission.

In the letter, scientists present the case of a previously healthy 24-year-old woman who was living in Paris and who became sick with the Zika virus in February.

“She was not receiving any medication, had not received any blood transfusions, and had never traveled to a region where Zika was epidemic or to tropical or subtropical areas,” the letter states.

The patient, who was sick for seven days, reported that she had recently had sexual contact with a man who had been in Brazil for several months before returning in February.

The sexual contact involved seven episodes of both vaginal sexual intercourse, without ejaculation, and oral sex with ejaculation.

According to the man, he had reported feeling ill with fever, chills, and a rash prior to returning to France.

Both patients were tested after the woman became ill. The man had high levels of the virus in his semen and urine, but none in his blood or saliva. The woman had the virus in her urine and saliva, and antibodies to the virus in her blood. But a vaginal swab was negative for the infection.

Scientists suggest that the data supports the hypothesis that Zika can be sexually transmitted.

“We cannot rule out the possibility that transmission occurred not through semen but through other biologic fluids, such as pre-ejaculate secretions or saliva exchanged through deep kissing,” the report states, noting that the saliva of the man tested negative 10 days after the onset of his symptoms. “Zika has been detected in saliva, but, to our knowledge, no cases of transmission through saliva have been documented.”

The scientists contend that the new data showed that health officials need to better define recommendations to prevent transmission of the virus, including creating guidelines regarding how long men who are returning from an area where active Zika transmission is occurring should continue to use condoms during sexual contact with pregnant women and those of child-bearing age are lacking.

Still, some health professionals believe the report doesn’t change much about the Zika virus.

“It shows you how elaborate the number of avenues of possible transmission can be,” Dr. William Schaffner, head of preventive medicine at Vanderbilt University Medical School, tells the New York Times.

Additionally, Dr. John T. Brooks, an epidemiologist at the Centers for Disease Control and Prevention studying sexual transmission of the Zika virus, tells the Times he was “not particularly surprised” by the reports findings.

[via The New York Times]

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