Aim: To determine if Mycobacterium ulcerans subsp. shinshuense is present in the common living environment in a case of familial concurrent occurrence of Buruli ulcer in Japan.
Materials & methods: Environmental samples were collected primarily from a water channel in the patient's residence. A combination of whole-genome amplification, touchdown PCR and DNA sequencing was used to detect M. ulcerans subsp. shinshuense DNA.
Results: M. ulcerans subsp. shinshuense DNA was detected in a crayfish sampled in July, but not in other samples including a crayfish sampled in October.
Conclusion: These findings support an association between contaminated aquatic environments and Buruli ulcer in Japan. The data also suggest dynamic seasonal appearance of the pathogen in the environment may contribute to the seasonal variation of Buruli ulcer occurrence in Japan.
Keywords: Buruli ulcer; Mycobacterium ulcerans subsp. shinshuense; aquatic environment; crayfish; familial concurrent occurrence of BU in Japan; vector.