Mary Lou Clements-Mann, longtime head of the Division of Vaccine Sciences in the Department of International Health at the School of Public Health, and her husband, Jonathan M. Mann, a visiting professor at Hopkins and dean of the School of Public Health at Allegheny University of the Health Sciences, died Sept. 2 in the Swissair jetliner crash off the coast of Canada.

The couple, both leaders in the world's fight against AIDS, were en route to a U.N. AIDS vaccine conference in Geneva. Both were 51.

"Mary Lou Clements-Mann and Jonathan Mann were distinguished and celebrated members of the faculty," said Alfred Sommer, dean of the School of Public Health. "Their loss will be felt deeply by all of us here and by the thousands, if not millions, of people who live better lives today because of their work."

In a news report following the crash, Dan Rutz, CNN medical correspondent, began his report by saying, "World leaders in the war against AIDS are in shock over the loss of two of their most trusted and admired colleagues."

Mary Lou Clements and Jonathan Mann--each of them a highly respected and renowned researcher--met while working together on an expert committee that was developing new strategies to fight disease. They married in 1996, and in 1997 Hopkins' Clements-Mann became a visiting professor in the Department of Cancer Biology at the Harvard School of Public Health, where her husband was the Francois-Xavier Bagnoud Professor of Health and Human Rights; the same year, Mann accepted an appointment as a visiting professor in the Department of Health Policy and Management in the Hopkins School of Public Health. He joined Allegheny University in Philadelphia this year.

"Theirs was a love story," Dean Sommer said. "Their devotion to one another and the happiness they obviously had together was obvious to all of us here at the school."

Raised in Longview, Texas, Mary Lou Clements-Mann graduated from Texas Tech University and received a medical degree from the University of Texas (Southwestern) Medical School in 1972. In 1975, she was awarded a D.T.M.H. from the University of London, London School of Hygiene & Public Health. She received a master of public health degree from Hopkins in 1979. In addition to her former position as head of the Division of Vaccine Sciences, Clements-Mann held joint appointments in the Department of Molecular Microbiology and Immunology in the School of Public Health and in the Department of Medicine, Division of Infectious Diseases, in the School of Medicine. She also served on the active medical staffs of Johns Hopkins Hospital and Bayview Medical Center.

Said Sommer, "Mary Lou devoted most of her life to developing and testing vaccines to combat the tragic illnesses brought on by bacterias and viruses."

At the time of her death, Clements-Mann was principal investigator for NIAID research projects titled "AIDS Vaccine Evaluation Unit" and "Operation of a Facility for the Study of Infectious Agents, Vaccines and Antimicrobials in Adult and Pediatric Human Subjects."

Jonathan M. Mann, born in Boston, was educated at Harvard College and was awarded a medical degree in 1974 by the Washington University School of Medicine. Postgraduate work included an internship in medicine at Beth Israel Hospital, Boston, and a master of public health degree from Harvard University in 1980.

Known as a leading advocate for the importance of human rights and its role in world health, Mann was a tenured professor at Allegheny; founder and director of the Francois-Xavier Bagnoud Center for Health and Human Rights at Harvard; director of the International AIDS Center, Harvard AIDS Institute; and chair of the Global AIDS Policy Coalition. He was for four years head of the Joint United Nations Program on HIV/AIDS, a program he had launched, and served as director of the International AIDS Conference six years ago in Amsterdam.

A memorial service will be held at 4 p.m., Sept. 16, in the East Wing Auditorium at the School of Public Health.