"So if my mom or grandma says they'll give me this tea and it makes me better, and someone comes up saying," Oh, that was just hocus pocus, I'll give you some real medicine, " ; what's the difference?" asked Baum, professor of infectious diseases at Imperial College London.
"We decided the difference is evidence: if you take a natural medicine and test it and it works, it's now a medicine too," Baum said. "So we created the soup project. We asked the children to bring the traditional soup their family would make when someone was not feeling well."
Sixty soups arrived, all incredibly diverse. The Children of Eden Primary School, which Braum's son Gilly and daughter Rudy attended, serves families across Europe, the Middle East and North Africa.
They should all be vegetarian, beef, or chicken soups that the family has passed down through the generations because of their restorative properties.
"The kids bought the cruder soups, even if we said no," Baum said. "The idea was to try to get some kind of clear extract."
Working with the children, Baum successfully filtered 56 of the soups, which he took back to the lab to test their medicinal attributes.
A deadly parasite
What would the test be? Why malaria, of course, since this is the work of Baum's life. He and his team from the Imperial College Department of Life Sciences study the most deadly species of the malaria parasite, called P. falciparum, responsible for 99% of malaria deaths.
Every year nearly half a million children die from malaria transmitted by infected mosquitoes, Baum said. Most are under five years old.
"We are currently at a kind of crossroads in global malaria control," Baum said. "We have had decades of progress in reducing the number of deaths at the turn of the millennium. But we have reached the point where we have halted our progress and there are some worrying signs of emerging drug resistance, just as if you had antibiotic resistance to bacteria." "
Even front-line antimalarial drugs, called artemisinin-based combination therapies, or ACTs, are beginning to lose their effectiveness as the parasite develops resistance.
"The malaria parasite is one of the very old parasites," said Baum. "It's a very complicated creature: it can change its shape, it can change its biology, and that makes developing new drugs and new therapies much more difficult."
A surprising result
At first, Baum and his team did not plan to conduct all 56 tests; after all, no one expected a soup to kill a malaria parasite.
"We thought to try," said Baum. "And we were surprised, some soups had a very good activity against the parasite."
In fact, five of the 56 soups blocked the growth of parasites in the human blood stage by about 50%; two of them were as effective as a leading antimalarial, didroartemisinin. Four other broths were able to block the male parasite's sexual development by about 50%.
"One of the most effective soups was a fermented cabbage-based vegetarian soup," Baum said. "And you know, people sing praises to kimchi and other fermented cabbages, so maybe there's something to it."
Baum published the results of the soup project on Monday in the BMJ newspaper. Will he discover the antimalarial ingredients in soups? No, this project is for others, he said.
"Many people work on testing purified natural products that have been taken from plants, from traditional medicines. Every now and then you find something that really works," Baum said.
One challenge, he continued, is that plants produce extremely complex molecules that science cannot yet synthesize, let alone produce on the massive scale needed to combat the worldwide transmission of malaria.
"But that should not stop us from looking," said Baum, pointing to his simple experiment in elementary school.
"It just shows that there may still be drugs to be discovered and that we should not roll our eyes at traditional medicine just because it has not been tested."