Triazole susceptibility of species: environmental survey in Lagos, Nigeria and review of the rest of Africa.

BACKGROUND

Triazole resistance is an emerging problem in the management of human aspergillosis globally and can arise in species which have been exposed to azole fungicides in the environment. We surveyed local government and council development areas in Lagos, Nigeria, to determine the distribution of species in the environment and their susceptibility to locally available triazole antifungal agents. We also reviewed the literature on the subject from the rest of Africa.

METHODS

A total of 168 soil samples from six locations in Lagos, Nigeria were processed and cultured on Saboraud dextrose agar impregnated with chloramphenicol to isolate species. Isolates were tested for susceptibility to itraconazole and voriconazole by microbroth dilution according to the European Committee on Antimicrobial Susceptibility Testing reference method. Relevant databases were searched to identify published work pertaining to triazole susceptibility of species in Africa.

RESULTS

A total of 117 species were isolated. was the most frequently isolated species (42.7%). Other species isolated were , 37 (31.6%), , 20 (17.1%), , 5 (4.3%) and , 5 (4.3%). All isolates were susceptible to itraconazole and voriconazole. The literature review showed documented evidence of triazole-resistant species from East and West Africa.

CONCLUSIONS

We found no triazole resistance in environmental isolates of in Lagos, Nigeria. Nevertheless, regular surveillance in clinical and environmental isolates is necessary in the light of findings from other African studies.