US doctors upgrade precautions on virus after finding it in saliva, urine

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.

STRONGER GUIDELINES FOR PREGNANT WOMEN

Reflecting concern over potential harm to fetuses, the CDC upgraded its guidelines on Friday for testing pregnant women who have traveled to affected areas, saying even those without symptoms should be tested after returning home.

The updated guidelines recommend pregnant women be offered testing 2 to 12 weeks after returning home. The agency had earlier suggested tests only for those with symptoms of the illness, which causes a fever, rash and red eyes.

In addition to widening its testing guidelines, the CDC noted the possibility of sexual transmission. It said men with a pregnant partner who live in or have traveled to an area of active Zika transmission and their partner should consistently and correctly use condoms during sex or abstain for the duration of the pregnancy.

Obstetricians have said that since 80 percent of those infected by the virus show no symptoms, many women have no way of knowing early enough to make an informed choice about their unborn child.

Scientists are racing to try to create a vaccine for Zika, but it could be years until that is available to the public. In the meantime, efforts to combat Zika are focused on protection from mosquito bites and eradication of the insect.

Brazilians have been rushing to buy repellant, creating a shortage of some brands on pharmacy shelves and boosting sales for the industry - a trend some producers are preparing for elsewhere as the outbreak spreads.

Brazil is particularly concerned to fight an outbreak as the country grapples with a deep economic crisis and prepares to host the Olympic Games in Rio de Janeiro in August, an event that draws huge crowds of athletes and spectators.

As concern grew over the virus in recent weeks, a string of airlines offered refunds or rebookings to people planning on traveling to affected areas.

The British government said on Friday that aircraft returning from affected countries would be sprayed with insecticide to check the spread of the disease.