FAILURE to diagnose gonorrhea in women who harbor asymptomatic infection is a significant handicap in the control of gonorrhea. This handicap would be partially alleviated if a culture method could be made readily available to all physicians and clinics. Similar considerations apply to detection of nasopharyngeal carriers of meningococci in confined populations. A selective medium for the cultivation of gonococci and meningococci was reported by Thayer and Martin in 1964 (1). An improved medium was described by the same authors in 1966 (2). The Thayer-Martin selective medium is recommended for primary isolation of the gonococcus and meningococcus, especially from sites where these organisms are outnumbered by the more rapid-growing natural bacterial flora. Overgrowth by gram-positive and other gram-negative bacteria and yeast is prevented in most cases because the medium contains 3 units of vancomycin, 7.5 micrograms of colistimethate sodium, and 12.5 units nystatin per milliliter. Although this selective medium has been available since 1964, its use, unfortunately, is limited to large hospitals and health centers closely associated with laboratory facilities. The average practitioner is handicapped in his diagnosis of asymptomatic gonorrhea by the hazards of transportation of suspected specimens to a distant laboratory. At present the most widely used tools for transporting secretions suspected of containing gonococci are the medium of Stuart and coworkers (3), a modified version of which was described by Amies in 1967 (4), and culture plates in candle jars (5). The procedure used by both Stuart and Amies is designed to eliminate oxidation as a cause of death of the gonococcus while the non-nutrient, non-toxic menstruum supresses growth of the gonococcus and other micro-organisms. Although these media seem to be effective in maintaining viability of organisms during transport times of less than 24 hours, their usefulness is somewhat restricted for longer transport periods. The candle jar may be used for transporting specimens, but this method is cumbersome and therefore less practical. An ideal transport medium for secretions suspected of containing gonococci and meningococci should be selective for these pathogens, have a prolonged shelf life, and be of rigid composition for mailing. In addition, it should preserve the viability of the organisms for more than 24 hours at ambient temperatures. Eliminating the required transfer from the non-nutrient transport medium to an isolation plate by combining the transporting vehicle with a culture medium would also be desirable. T'he authors are with the Venereal Disease Research Laboratory, Venereal Disease Branch, State and Community Services Division, Center for Disease Control, Health Services and Mental Health Administration, Public Health Service. Tearsheet requests to John E. Martin, Jr., Venereal Disease Research Laboratory, Center for Disease Control, Atlanta, Ga. 30333.
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