Brazilian scientists announced on Friday they had found Zika in the saliva and urine of two patients, as U.S. health officials advised more stringent measures for monitoring pregnant women for Zika and preventing sexual transmission of the virus.
The disease that has spread rapidly through the Americas and led to a global health scare over its possible link to severe birth defects, is primarily transmitted by mosquito. The possibility of infection via body fluids complicates efforts to combat the outbreak.
Scientists at the Oswaldo Cruz Foundation, a public health institute in Brazil, said they used genetic testing to identify the virus in samples from two patients while they had symptoms and were known to have Zika. The scientists stressed, however, that more studies were needed to determine if those fluids could transmit the infection.
It was the first time the virus has been detected in saliva and urine, the scientists told reporters in Rio de Janeiro. The virus was deemed active, meaning that it was able to cause infection. But Myrna Bonaldo, one of the scientists who made the discovery, noted that this “is not proof that it can contaminate other people through those fluids.”
The discovery added to concern that Zika, which is predominantly spread by the Aedis aegypti mosquito, could also be transmitted by other means.
Scientists are researching reports earlier this week that an American had transmitted the virus to a sexual partner in Dallas County, Texas. And Brazilian health officials said on Thursday they had confirmed two cases of transmission through blood transfusions.
At the center of the concern over Zika, until recently viewed as a mild illness, is the possibility that infection with Zika during pregnancy may cause microcephaly, a condition marked by abnormally small head size that can cause permanent brain damage in newborns.
One of America’s top doctors, the director of the U.S. Centers for Disease Control, said on Friday the suspected link appears “stronger and stronger” as researchers study whether there is a causal connection.
CDC Director Dr. Tom Frieden said the agency is also working with researchers in Brazil to study a potential link between Zika and a wider array of developmental disorders in babies.
The outbreak of Zika infections, which started in northeastern Brazil, has been linked to more than 4,000 suspected cases of microcephaly in the country. The virus has since spread and been locally transmitted in more than 30 countries according to the World Health Organization, which has declared a global health emergency over Zika.