Sensitivity of trachoma agent to streptomycin and related antibiotics

For isolating trachoma (TRIC) agent from conjunctival scrapings, both streptomycin and neomycin were effective in preventing bacterial contamination, but at high concentrations neomycin was rather more inhibitory to TRIC agent. Prolonging storage of scrapings with neomycin at 4 degrees from 30 min. to 24 hr. reduced the bacterial contamination rate, but also diminished the chance of isolating TRIC agent at the 1st passage. Two freshly isolated TRIC agents differed in their susceptibility to neomycin and streptomycin. Kanamycin and framycetin appeared to be less suitable than streptomycin for use in isolation of TRIC agent. In isolation studies, the possibility of inhibiting TRIC agent by high concentrations of antibotics, including streptomycin, should be borne in mind.