Evaluation of four commercial transport media for the survival of Neisseria Gonorrhoeae

We evaluated four commercial transport systems with a standardized inoculum of clinical isolates of N. gonorrhoeae (NG), and assessed survival after h olding for up to 48 hours at both ambient and refrigeration temperatures. S uspensions of clinical isolates of NG were standardized and adsorbed onto f our transport swab types: Culturette EZ(TM) (Becton Dickinson [BD], Cockeys ville, MD, USA); Cultureswab(TM) (Difco Laboratories, Detroit, MI, USA); Ve nturi Transystem(TM) (Copan Italia, Bovezzo, Italy); and a recently modifie d Starswab(TM) (Starplex Scientific, Etobicoke, ON). Swabs were plated to c hocolate agar at 0, 6, 24, and 48 hours, and colonies counted. Each swab ty pe was tested in quadruplicate with each NG strain for all time and tempera ture variables. There was a marked reduction in NG CFUs after only 6 hours incubation with each of the swabs tested. Survival was best using Venturi T ransystem(TM) and Cultureswab(TM) transports (colony counts were reduced to 15.3% and 13.0%, respectively, at 6 hours) when compared with the Culturet te EZ(TM) and Starswab(TM) (colony counts were reduced to 2.2% and 4.3%, re spectively, at 6 hours). After the 24-hour holding period, 94% of the cultu res from the Venturi Transystem(TM) were positive, 82% from the Cultureswab (TM), 24% from the Starswab(TM); and 17% from the Culturette EZ(TM). After 48 hours, recovery dropped to 72%, 43%, 14%, and 0.04%, respectively. All o f the systems tested had at least an 80% decrease in recovered colonies aft er only 6 hours. Further studies are required to determine how poor transpo rt conditions influence the number of positive cultures and what the public health implications are. Of the swabs tested, Cultureswab(TM) and Venturi Transystem(TM) were most acceptable. (C) 2000 Elsevier Science Inc. All rig hts reserved.