But after returning from a stint working in another village, Sherman learned the girl had died of malaria. And after completing his service in 2002, he learned two women who had been like mothers to him also died of the mosquito-borne disease.
Their deaths, and the deaths of more than 1 million people each year from malaria, prompted Sherman and fellow Saint Louis University medical student Jesse Matthews to start NetLife, a nonprofit organization that distributes mosquito nets in Africa. Its motto: Saving lives one net at a time.
"Previously when we bought them, they were $8.50 a net. That's way more than a typical villager in Senegal could afford," said Sherman, 29. The group, which now buys nets for $5 each, distributes them for free in remote villages where people don't have them.
The concept sounds almost too straightforward. But the docs-in-training say the nets work, and health agencies agree.
The malaria parasite, which is primarily transmitted by the female anopheles mosquito, is the leading cause of death in African children under age 5, Sherman and Matthews said. Tens of millions of people suffer chronically from the debilitating disease, even though it is preventable and curable.
Because the mosquitoes that cause malaria are largely active from dusk to dawn, insecticide-treated mosquito nets hung over beds are an inexpensive way to help prevent malaria, the two said.
Sherman and Matthews buy the nets, pay their own costs and take them to rural Senegal in west Africa, biking between villages in sometimes oppressive heat to distribute them.
"It's beautiful, green, semi-mountainous. The earth is a red color. Where we bike is relatively untouched," said Matthews, 27, of Poulsbo, Wash.
The two last went to Africa in 2005 to distribute 600 nets, and plan to return again this summer for 10 weeks to deliver 1,000 more. Before dropping off the nets, they scout out a village, talk to the chief and make a list of women in the community. Then, they return later with the nets, involve villagers in a skit explaining the specifics on how to use them and keep them from getting damaged. They then distribute them to the women, who make sure their families are protected by the net when they sleep.
The reaction in the African villages is immediate: "Every time we give out the nets, there's a big dance party and we cannot stop it," Sherman said.
Nationally, other efforts to distribute mosquito nets have gotten some high-profile support.
In December, First Lady Laura Bush suggested American school children could donate $10 each to buy insecticide-treated nets for Africa.
Sports Illustrated columnist Rick Reilly has urged readers to make donations to buy anti-malaria bed nets to the "Nothing But Nets" campaign through the United Nations Foundation.
He asked them to donate $20 for mosquito nets to be distributed in Africa if they had "ever gotten a thrill by throwing, kicking, knocking, dunking, slamming, putting up, cutting down or jumping over a net ..."
Sherman and Matthews said all the focus on donating the treated mosquito nets can only help the cause.
Netting Nations, a California-based organization that also distributes insecticide-treated mosquito nets, recently donated $1,000 to NetLife's efforts. The group liked that Sherman and Matthews were medical students who had no overhead costs and distribute the nets themselves, said director Ben Kingston.
"It definitely comes from an altruistic place," he said. "They wanted to make a profound difference in other people's lives and that was something we identified with."
Sherman and Matthews said by raising the funds, buying the nets, and distributing them personally, they know they're getting directly into the hands of those in need.
"There's a completeness about the way we do it, and I'm really proud of it," Sherman said.