Incubation time, second blind passage, and cost considerations in the isolation of Trichomonas vaginalis.

In a group of 247 symptomatic and asymptomatic women, 75 (30.3%) were found to harbour Trichomonas vaginalis; 39 (52%) infections were detected by wet mount and 36 (48%) were detected by culture only. Of the latter, 27 produces a positive culture in 3 days or less and 9 were positive, on average, at day 6. The break even cost of culture was $6.75 per patient. Among 70 wet mount-negative, primary culture-negative specimens that received a blind passage, another 3 (4.2%) positive cultures were detected.