Introduction
The WHO yaws eradication strategy consists of one round of total community treatment
(TCT) of single-dose azithromycin with coverage of > 90%.The efficacy of the strategy to
reduce the levels on infection has been demonstrated previously in isolated island communities
in the Pacific region. We aimed to determine the efficacy of a single round of TCT with
azithromycin to achieve a decrease in yaws prevalence in communities that are endemic for
yaws and surrounded by other yaws-endemic areas.
Methods
Surveys for yaws seroprevalence and prevalence of skin lesions were conducted among
schoolchildren aged 5±15 years before and one year after the TCT intervention in the
Abamkrom sub-district of Ghana. We used a cluster design with the schools as the primary
sampling unit. Among 20 eligible primary schools in the sub district, 10 were assigned to the
baseline survey and 10 to the post-TCT survey. The field teams conducted a physical examination
for skin lesions and a dual point-of-care immunoassay for non-treponemal and treponemal
antibodies of all children present at the time of the visit. We also undertook surveys
with non-probabilistic sampling to collect lesion swabs for etiology and macrolide resistance
assessment.
Results
At baseline 14,548 (89%) of 16,287 population in the sub-district received treatment during
TCT. Following one round of TCT, the prevalence of dual seropositivity among all children
decreased from 10.9% (103/943) pre-TCT to 2.2% (27/1211) post-TCT (OR 0.19; 95%CI
0.09±0.37). The prevalence of serologically confirmed skin lesions consistent with active
yaws was reduced from 5.7% (54/943) pre-TCT to 0.6% (7/1211) post-TCT (OR 0.10; 95%
CI 0.25±0.35). No evidence of resistance to macrolides against Treponema pallidum subsp.
pertenue was seen.
Discussion
A single round of high coverage TCT with azithromycin in a yaws affected sub-district adjoining
other endemic areas is effective in reducing the prevalence of seropositive children and
the prevalence of early skin lesions consistent with yaws one year following the intervention.
These results suggest that national yaws eradication programmes may plan the gradual
expansion of mass treatment interventions without high short-term risk of reintroduction of
infection from contiguous untreated endemic areas.
