Characterization of microbial flora of leprous ulcers infested with maggots

Swabs from 64 maggot infested leprosy ulcers before and after treatment for maggots and 100 non-infested leprosy ulcers were studied for the bacterial flora. From maggot infested ulcers (before treatment), the cultures usually showed mixed growth. Among the Gram positive isolates, Staphylococcus aureus (37%), S. albus (18%) and Streptococcus pyogenes (36%) were frequently isolated. Gram negative bacteria isolated were Proteus spp. (21%) and Escherichia coli (7%). Anaerobic bacteria isolated were Micrococcus (3%) and Bacteroides (4%). After treatment of maggot infested ulcers, S. aureus (36%) continued to be isolated with almost the same frequency. The isolates of other Gram negative organisms were slightly reduced. Among the Gram negatives the Proteus spp. (10%) were also less in number. In few cases Neisseria (3%) was found. Anaerobic isolates were M. luteus (2%) and B. necrophorus (3%). From the cases without maggot infestation, a single organism was isolated from 16 cases and 84 mixed cultures were obtained. Isolates included the aerobic Gram positives S. aureus (46%), S. albus (21%) and S. pyogenes (38%), and the Gram negative Proteus spp. (19%) and E. coli (7%). The anaerobic isolate was M. luteus (3%). From this study no apparent association between the type of bacterial flora and maggot infestation could be observed.