Stephen Kurczy

Rio de Janeiro—When Davis Fernandes Ferreira’s two-year-old daughter was bit by a mosquito this month, he assumed the worst: Zika, a fast-spreading virus that has killed more than 40 people in Brazil this year and spurred authorities to declare a national health emergency.

He then made her a secret tea.

It was a herbal tea made from a plant that Dr. Ferreira, one of Brazil’s leading experts on mosquito-borne diseases, recently identified in his laboratory as effective in combating dengue and potentially Zika, which are in the same viral family.

The plant, which Dr. Ferreira declined to name, has not yet been approved for testing on animals or humans, but it is has long been used in some Brazilian communities as a traditional herbal medicine. No proven antiviral treatment currently exists for dengue or Zika.

“I know it works in vitro,” Dr. Ferreira, vice director of the Institute of Microbiology at the Federal University of Rio de Janeiro, told Fusion during an interview at his laboratory, surrounded by refrigerators full of blood vials and plant extracts. “We know it’s safe because people already drink it.”

It turned out that the mosquito that bit his daughter carried no pathogens, but Dr. Ferreira’s action highlighted his conviction that the remedy works.


There are just two big hurdles for turning this traditional herbal tea into an accepted medical treatment: layers of time-consuming bureaucracy to gain approval for animal and human testing, and money. Experts hope that the severity of the Zika epidemic will spur a quick resolution to those hurdles.

Alarmingly, Zika has been linked for the first time ever to an outbreak of microcephaly, which causes newborns to be born with shrunken skulls and underdeveloped brains. Brazil’s Health Ministry says there have been 2,782 suspected Zika-related microcephaly cases so far this year, compared to 147 in all of 2014, and has advised millions of women against getting pregnant altogether.


The outbreak of Zika, a virus that originated in Africa and is suspected of first coming here during the 2014 World Cup, has set off international alarms.

“Brazil's Zika outbreak is a major concern,” says Dennis Brown, a professor in the department of molecular and structural biochemistry at North Carolina State University. “Its implication in birth defects is alarming."


Dr. Brown, whose laboratory has created successful vaccines for dengue and chikungunya, called Ferreira “an internationally recognized authority on arthropod-borne diseases” whose research helps keep him informed regarding the status of dengue and Zika in South America. He said the Zika outbreak had already prompted him to obtain approval from the US Centers for Disease Control to bring the virus into his lab so he could also work on a vaccine.

But could the secret weapon to combating dengue and Zika simply be a green thumb? It all almost sounds too good to be true that a common plant could be cultivated freely at home or in the garden, and its leaves mixed into a herbal tea that would inhibit these deadly viruses.

A plant extract in Brazil could hold the remedy to Zika and dengue
Stephen Kurczy


Jonas Schmidt-Chanasit of the Bernhard Nocht Institute for Tropical Medicine in Hamburg, Germany, told Fusion that it’s not unheard of for the natural world to hold a simple solution to a deadly virus. He cited how Chinese pharmaceutical chemist Tu Youyou received the 2015 Nobel Prize in Medicine for her discovery of the malaria treatment artemisinin, which she identified through first consulting traditional medicines and folk remedies for leads on herbs and plants.

“It is indeed an interesting finding which needs further evaluation and research,” Dr. Schmidt-Chanasit, who is also deputy director of the World Health Organization’s Collaborating Centre for Arbovirus & Haemorrhagic Fever Reference & Research, said of Ferreira’s findings. “Funding is urgently needed.”

Funding, however, is in short supply as the Brazilian government slashes spending amid the worst economic recession since the Great Depression. Brazilian researchers largely rely on grants from the state and federal governments, unlike in the United States where private pharmaceutical companies pump tens of millions of dollars annually into academic research.


“There’s really a lack of funding for research here in Brazil,” says Dr. Bergmann Ribeiro, president of the Brazilian Society for Virology and a professor at the University of Brasília. He agrees that Ferreira’s discovery merited further investment and testing, adding that Brazil’s rich biodiversity is an underutilized source for combating diseases.

The Brazilian doc thinks this test tube holds the remedy to the deadly viral outbreak
Stephen Kurczy

“If nobody puts money into it, it’s not possible [to develop],” he told Fusion. “Where can you find new antibiotics? In plants. In microorganisms. In the biodiversity of South America and the Amazon. But to develop that, you need the basic research. [Ferreira] needs money and more people to develop this into a medicine.”


There is also debate over the best way to tackle dengue and Zika, be it through funding preventative measures such as a vaccine, or in targeting the mosquito with rigorous surveillance systems, or even through biologically re-engineering the mosquito so that the pathogen-carrying Aedes aegypti species is killed off. Dr. Ribeiro, for his part, believes the focus for now should be on combating mosquitoes through chemical sprays and educating people to eliminate pools of standing water where mosquitoes breed.

“The most important thing now is to kill the mosquitoes,” Ribeiro insists.

Back on the campus of the Federal University of Rio de Janeiro, Dr. Ferreira shakes his head over the ability of the tiny Aedes aegypti mosquito to inflict such suffering on humans and to adapt so quickly to all types of environment, from the African jungle to the concrete streets of Rio de Janeiro. The Ministry of Health has mobilized 40,000 teams nationwide to fight Aedes aegypti, while the host city of the 2016 Olympics has also stepped up neighborhood-visits to eradicate stagnant pools and monitor pregnant women suspected of having Zika infections.


“It’s a very tough war against the mosquito and I don’t see how we can win right now,” Ferreira says.  “We’re a few months from the Olympics and we have this whole problem on our hands. We have to do everything we can to tranquilize it.”

Stephen Kurczy, a Brazil correspondent, has reported from the favelas of Rio de Janeiro to the jungles of the Amazon. Somewhere along the way he became addicted to açaí, a purple slushy made from the powerfruit.