Yet no randomized, controlled trial has shown that screening reduces long-term complications from chlamydia. And studies that do show a value have not been well-designed, while tending to overestimate the cost-effectiveness of the screening programs, Low noted.
Low argued that a consistent definition of "screening program" is needed and that screening programs for all diseases should be standardized.
"There is a difference between 'screening' and a 'screening program,' " Low said. "Any benefits of screening in a population will only be achieved if screening is implemented as a program. This means regular repeated screening of all those in the target population. Opportunistic screening as usually practiced does not ensure that people who have been screened once are invited for subsequent screening tests."
The bottom line, according to the Swiss expert: "Low overall coverage and infrequent screening will not control the spread of an asymptomatic, infectious disease."
There also needs to be more research to determine if screening programs really are effective, especially the more targeted, proactive kind, Low said. "There are trials of proactive chlamydia screening showing a benefit after one round of screening," she said. "The sustainability and duration of benefit of this approach to screening are therefore unknown."
Any screening program shouldn't replace prevention, another expert stressed.
"Prevention is really the best way to go, and sexually transmitted diseases are no exception to that rule," said Dr. Patricia Sulak, professor of obstetrics and gynecology at Texas A&M Health Science Center College of Medicine and an ob/gyn at Scott & White Hospital in Temple, Texas.
"Really, the best way for us to reduce problems is to look at the source of the problems, and that's multiple sexual partners," she said. "The earlier you start having sex, the greater the chance of becoming infected. We want to make sure we get prevention across."
For more on chlamydia, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Nicola Low, M.D., reader, epidemiology and public health, department of social and preventive medicine, University of Bern, Switzerland; Fred Wyand, spokesman, American Social Health Association, Research Triangle Park, N.C.; Patricia Sulak, M.D., professor, obstetrics and gynecology, Texas A&M Health Science Center College of Medicine and ob/gyn, Scott & White Hospital, Temple, Texas; April 7, 2007, British Medical Journal