Brazil researchers hope to test Zika virus treatment in a year

Leading researchers in Brazil are borrowing techniques used to accelerate the fight against Ebola in the hope of developing a Zika virus treatment that could be tested in humans in a year.

Professor Jorge Kalil, head of the state-run Butantan Institute, told Reuters this week that scientists there planned to use animals to produce antibodies to tackle the virus, which is suspected of causing brain damage in more than 4,000 infants in the South American country. A similar research path was used in the hunt for an Ebola treatment.

There is no cure or vaccine for the virus, which was discovered in the Zika forest in Uganda in 1947. It was detected in Brazil for the first time last year and has since spread to at least 26 countries in the Americas. The virus has mild effects - red eyes, fever, joint pains and a rash - and nearly 80 per cent of people who are infected experience no symptoms.

The World Health Organization (WHO) recently declared an emergency over Zika, lending urgency to research into whether Zika infection in pregnancy does in fact cause microcephaly, a condition marked by abnormally small heads, in newborns. Brazil is investigating 4,074 suspected cases of microcephaly.

Kalil, an immunologist, said the institute was cultivating the virus in quantities sufficient to start tests in isolating antibodies in rodents. Researchers would then attempt to produce them in larger quantities in horses and purify the antibodies in the laboratory before starting tests on humans.

"The antibodies ... could be injected into women with Zika to neutralise the virus," Kalil told Reuters in an interview. "I think we can reach that point in a year."

Researchers do not have a clear model of how the virus operates in animals or humans. Several organisations are working on the problem in rodents and primates because of the urgency, Kalil said.

Scientists generally prefer to use human antibodies in drugs because the immune system might react to them, but it has been done. Such was the case of early versions of Mapp Biopharmaceutical Inc's ZMapp antiviral treatment for Ebola, which was developed in mouse blood cells that were exposed to samples containing Ebola virus fragments.