Elimination of Staphylococcus intermedius in healthy dogs by topical treatment with fusidic acid.

Cutaneous and mucosal carriage of Staphylococcus intermedius was investigated in six healthy beagles before and after application of fusidic acid to mucosal surfaces as 1 per cent viscous eye drops twice daily for seven days. Bacterial populations were determined repeatedly over four weeks using quantitative techniques. The overall cutaneous populations of S intermedius reduced significantly (P < 0.001) two days after treatment but returned to pretreatment levels after a further week. The mucosal frequency of S intermedius reduced significantly (P < 0.01) two days after treatment and remained reduced (P < 0.01) at the end of the study. The mucosal populations were also reduced (P < 0.01) two days after treatment and remained lower (P < 0.05) after a further week. No such changes occurred in the control group of six beagles. The study indicates the importance of mucosae as carriage sites for S intermedius in dogs. This form of therapy may be useful as an additional tool against canine recurrent pyoderma.