Macrolide resistance in yaws

The mutation, A2059G, was previously reported in a patient with syphilis (caused by T p pallidum) with spiramycin treatment failure;2 it is one of two macrolide-resistant mutations previously detected in T p pallidum (the other is A2058G). Since its discovery, the A2059G mutation has been detected in T p pallidum isolates from patients with syphilis from Argentina,3 China,4 Czech Republic,5,6 the UK,7 Madagascar,8 and the USA.8,9 Despite direct observation of the emergence of the A2059G mutation, which causes macrolide resistance in T p pertenue, the clinical study setting does not allow an accurate estimation of the frequency of emergence of mutations capable of causing macrolide resistance in T p pertenue. In the group of participants (including adults) treated in this study, the estimated number of all people infected with T p pertenue could reach several thousands at the baseline and the probability of a de-novo emergence of mutations causing macrolide resistance is therefore less than 10−3 per treated patient. The index case shows that follow-ups occurring 2 weeks after medication can miss treatment failures caused by the emergence of de-novo mutations, which enables macrolide-resistant T p pertenue to spread during the 5·5 months between the 2-week follow-up and the next total targeted treatment survey. [...]it might be beneficial to include a clinical manifestation follow-up 2 months after treatment to identify T p pertenue infections with possible de-novo mutations and thus prevent their potential spread.