LOS ANGELES, DEC. 16 -- David Werner, who won international recognition for three decades of championing health care for children in developing countries, was quietly removed from the nonprofit foundation he headed last year after board members alleged he had sexually abused some of the disabled children he brought to the United States for treatment.

Werner -- who won a $335,000 MacArthur Foundation Genius Grant in 1991 and whose self-help medical manual, "Where There Is No Doctor: A Village Health Care Handbook," has sold more than 2 million copies -- resigned after board members at the Hesperian Foundation in Palo Alto filed a complaint with local police. It accused him of molesting at least 20 boys ranging from 10 years to puberty.

The molestations occurred in his Palo Alto home, in a summer home in New Hampshire and in the village in Mexico where he had worked since the early 1960s, according to the foundation's complaint. Several board members said today they had been aware of Werner's sexual activities for several years but had maintained silence for the sake of the foundation's work.

The current Hesperian president, Davida Coady, who reported the alleged abuse to police in August 1993, said in a telephone interview that Werner had admitted to her last year that he had had sex with boys but felt it was part of a "mentoring and parenting relationship." Other board members said Werner had made similar admissions to them.

Werner, who is 60, did not return repeated telephone messages left at his home. But his attorney, Paul Meltzer, said: "Mr. Werner is in a bitter dispute with the Hesperian Foundation over royalties for a book he wrote. These allegations have been fully investigated by the police and there has been no prosecution because there is no case."

In a letter to the San Jose Mercury News, which first reported the allegations, Werner said investigations by the police and Hesperian officials had "turned up nothing."

"For me to care so intensely for the well-being of these children has put me in a vulnerable position -- I am accused of having extended my intense caring for children into the realm of sexual abuse. I categorically deny that I have sexually abused any children," said Werner, who was a biology teacher at a Palo Alto alternative school before founding the Third World self-help organization.

Coady, a pediatrician from Berkeley, said the letter, like the statements made to Hesperian board members, implied a distinction between having sex with youths and abusing them. She said Werner insisted that Americans "had trouble accepting diversity," and that his removal from the board was the result of homophobia. She said Werner also argued the relationships were a "positive influence" on the children.

More than a year after the Hesperian board members filed their complaint, police have not questioned him.

Detective Sgt. Dennis Burns, in a telephone interview, said board members had not identified any of the alleged victims by name and that "unless we get specific information concerning victims in our jurisdiction, the department is not going to investigate."

Coady, however, said she had given another detective, Luis Verbera, a list of the names of 20 boys, some as young as 10 years, whom she described as victims of sexual abuse. She said 17 were Mexican, two American and one Australian. The alleged victims included youths who were designated for treatment at the Shriner's Hospital in nearby San Francisco, she said.

Coady said that a board member and three staff members had confronted Werner with allegations of sexual abuse as early as 1991 and threatened to report it to police, and that Warner had admitted then that he had had sex with boys.

She said that when she assumed the presidency of Hesperian last year, she was "astounded" to learn that the foundation officials, in an attempt to preserve Werner's valuable work, had issued a set of conditions governing his sexual activity relationships with minors. The principal conditions, Coady said, were that the youths had to be 16 years or older and that the "relationships" must not become "intertwined" with his work for Hesperian.

Former board member Greg Troll, a physician in Yosemite, Calif., said Werner admitted to him in 1987 or 1988 he had had sex with young boys when he and other foundation officials confronted him.

Troll said he and other officials decided not to file a complaint because Werner had made a "fairly solemn commitment" that the relationships would end.

Board member Medea Benjamin said she was uncertain whether Werner's sexual activities were wrong: "It brings up all kinds of dilemmas I never thought about before. But, as board members, we had to consider the legal issues involved." Werner gained fame for his work in aiding the ill and disabled of the world's poorest nations. His self-help medical handbook, first published in 1977, offers easy-to-understand advice and pictures and is used in more than 100 countries.

Special correspondent Kathryn Wexler contributed to this report.