Mapping Trachoma in the Solomon Islands: Results of Three Baseline Population-Based Prevalence Surveys Conducted with the Global Trachoma Mapping Project

Abstract

Purpose: We sought to complete the baseline trachoma map of the Solomon Islands by establishing prevalences of active trachoma and trichiasis in the provinces of Choiseul, Western, Rennell-Bellona, and Temotu. Methods: Using the standardized methodology developed for the Global Trachoma Mapping Project, we conducted cross-sectional community-based surveys from September to November 2013. Choiseul and Western provinces were each mapped as separate evaluation units (EUs); Rennell-Bellona and Temotu were combined to form a third EU. Results: A total of 9819 individuals were sampled for inclusion, with 9224 (93.3%) consenting to examination, of whom 4587 (46.3%) were female. Survey teams visited 82 villages, and surveyed 2448 households. Two EUs had prevalences of trachomatous inflammation – follicular (TF) in 1–9-year-olds over the 10% threshold at which WHO recommends mass distribution of azithromycin for at least 3 years (Western 20.4%, 95% confidence interval, CI 15.6–26.3%; Rennell-Bellona/Temotu 22.0%, 95% CI 18.5–26.0%). Choiseul had a TF prevalence of 6.1% (95% CI 4.1–8.6%), and met the criterion for a single round of mass antibiotic distribution before re-survey. The adjusted prevalences of trichiasis in those aged 15+ years were 0.0% (95% CI 0.0–0.2%) in Choiseul, 0.16% (95% CI 0.0–0.5%) in Western, and 0.10% (95% CI 0–0.3%) in Rennell-Bellona/Temotu provinces. All three EUs require implementation of the facial cleanliness and environmental improvement components of the trachoma elimination strategy. Conclusion: Active trachoma is prevalent in the Solomon Islands. However, there is little evidence of the blinding complications of trachoma being a public health problem there. Further research into the explanation for this phenomenon is warranted.

Feasibility and safety of mass drug coadministration with azithromycin and ivermectin for the control of neglected tropical diseases: a single-arm intervention trial

“…The Solomon Islands has high levels of both trachoma 22 , 23 and scabies. 24 , 25 On the basis of WHO SAFE strategy guidelines, mass administration of azithromycin for trachoma was implemented by the Ministry of Health and Medical Services across all ten provinces from 2014 to 2015.…”

“… 24 , 25 On the basis of WHO SAFE strategy guidelines, mass administration of azithromycin for trachoma was implemented by the Ministry of Health and Medical Services across all ten provinces from 2014 to 2015. 22 , 26 , 27 With emerging data on the effectiveness of ivermectin mass administration for scabies control, 17 we did a trial which aimed to address outstanding questions on the feasibility and safety of large-scale coadministration of regimens based on ivermectin and azithromycin in Choiseul Province, the last province scheduled to receive mass drug administration for trachoma.…”

Ocular Chlamydia trachomatis infection, anti-Pgp3 antibodies and conjunctival scarring in Vanuatu and Tarawa, Kiribati before antibiotic treatment for trachoma

“…Data from the Solomon Islands, 12 Vanuatu 13 and Papua New Guinea 14 have shown the epidemiology of trachoma in Melanesia to be unusual in that TT is rare or absent despite a moderate prevalence of TF. In contrast, in Kiribati, both TF and TT exceed the prevalence threshold for trachoma to be considered a public health problem.…”

Impact of the Global Trachoma Mapping Project

“…For example, in the Pacific Island region the prevalence of TF among 1-9 year-olds was often greater than 10%, but TT among older individuals was much loweran unexpected pattern that requires further study but suggests that surgical programs are not a great need in this region. 4,5 GTMP surveys in Chad 6 and Senegal 7 found the opposite pattern, with many evaluation units (EUs) showing a prevalence of TF below the WHO threshold for elimination (<5% TF) and a prevalence of trachomatous trichiasis above the elimination threshold (<0.2% TT), suggesting that surgical programs are a more urgent need. Achieving national elimination requires reaching WHO thresholds for both TF and trachomatous trichiasis and it is likely to be the latter that will be a major challenge in the coming years.…”