Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands

Butcher, RMR, Sokana, O, Jack, K, Macleod, CK, Marks, ME, Kalae, E, Sui, L, Russell, C, Tutill, HJ, Williams, RJ, Breuer, J, Willis, R, Le Mesurier, RT, Mabey, DCW, Solomon, AW and Roberts, Ch. 2016. Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands. [Online]. Figshare. Available from: https://doi.org/10.1371/journal.pntd.0004863

Butcher, RMR, Sokana, O, Jack, K, Macleod, CK, Marks, ME, Kalae, E, Sui, L, Russell, C, Tutill, HJ, Williams, RJ, Breuer, J, Willis, R, Le Mesurier, RT, Mabey, DCW, Solomon, AW and Roberts, Ch. Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands [Internet]. Figshare; 2016. Available from: https://doi.org/10.1371/journal.pntd.0004863

Butcher, RMR, Sokana, O, Jack, K, Macleod, CK, Marks, ME, Kalae, E, Sui, L, Russell, C, Tutill, HJ, Williams, RJ, Breuer, J, Willis, R, Le Mesurier, RT, Mabey, DCW, Solomon, AW and Roberts, Ch (2016). Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands. [Data Collection]. Figshare. https://doi.org/10.1371/journal.pntd.0004863

Description

Trachoma is endemic in several Pacific Island states. Recent surveys across the Solomon Islands indicated that whilst trachomatous inflammation-follicular (TF) was present at levels warranting intervention, the prevalence of trachomatous trichiasis (TT) was low. We set out to determine the relationship between chlamydial infection and trachoma in this population. We conducted a population-based trachoma prevalence survey of 3674 individuals from two Solomon Islands provinces. Participants were examined for clinical signs of trachoma. Conjunctival swabs were collected from all children aged 1-9 years. We tested swabs for Chlamydia trachomatis (Ct) DNA using droplet digital PCR. Chlamydial DNA from positive swabs was enriched and sequenced for use in phylogenetic analysis. We observed a moderate prevalence of TF in children aged 1-9 years (n = 296/1135, 26.1%) but low prevalence of trachomatous inflammation-intense (TI) (n = 2/1135, 0.2%) and current Ct infection (n = 13/1002, 1.3%) in children aged 1-9 years, and TT in those aged 15+ years (n = 2/2061, 0.1%). Ten of 13 (76.9%) cases of infection were in persons with TF or TI (p = 0.0005). Sequence analysis of the Ct-positive samples yielded 5/13 (38%) complete (>95% coverage of reference) genome sequences, and 8/13 complete plasmid sequences. Complete sequences all aligned most closely to ocular serovar reference strains. The low prevalence of TT, TI and Ct infection that we observed are incongruent with the high proportion of children exhibiting signs of TF. TF is present at levels that apparently warrant intervention, but the scarcity of other signs of trachoma indicates the phenotype is mild and may not pose a significant public health threat. Our data suggest that, whilst conjunctival Ct infection appears to be present in the region, it is present at levels that are unlikely to be the dominant driving force for TF in the population. This could be one reason for the low prevalence of TT observed during the study.

Methods

Description of data capture

We conducted a population-based trachoma prevalence survey of 3674 individuals from two Solomon Islands provinces. Participants were examined for clinical signs of trachoma. Conjunctival swabs were collected from all children aged 1–9 years. We tested swabs for Chlamydia trachomatis (Ct) DNA using droplet digital PCR. Chlamydial DNA from positive swabs was enriched and sequenced for use in phylogenetic analysis.

Data capture method

Experiment

Data Collection Period

From	To
October 2013	November 2013

Date (Date published in a 3rd party system)

7 September 2016

Geographical area covered (offline during plugin upgrade)

North Latitude	East Longitude	South Latitude	West Longitude
-9.18141	160.823	-10.1237	159.472

Language(s) of written materials

English

People & Groups

Data Creators	Butcher, RMR, Sokana, O, Jack, K, Macleod, CK, Marks, ME, Kalae, E, Sui, L, Russell, C, Tutill, HJ, Williams, RJ, Breuer, J, Willis, R, Le Mesurier, RT, Mabey, DCW, Solomon, AW and Roberts, Ch
LSHTM Faculty/Department	Faculty of Infectious and Tropical Diseases > Dept of Clinical Research
Participating Institutions	London School of Hygiene & Tropical Medicine, London, United Kingdom, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands, University College London Hospitals, London, United Kingdom, Lata Hospital, Lata, Santa Cruz, Solomon Islands, Bellona Rural Health Centre, Bellona, Solomon Islands, University College London, London, United Kingdom, Task Force for Global Health, Decatur, Georgia, United States of America, Royal Victorian Eye and Ear Hospital, Melbourne, Australia, University of Melbourne, Melbourne, Australia

Projects

Funders

Project	Funder	Grant Number	Funder URI
UNSPECIFIED	Wellcome Trust	098521/B/12/Z	UNSPECIFIED
UNSPECIFIED	Department for International Development	UNSPECIFIED	UNSPECIFIED

Additional Information

Date Deposited	04 Oct 2016 12:14
Last Modified	27 Apr 2022 18:20
Publisher	Figshare

Downloads

Data Visualisation

S1_Figure Download

Filename: S1_Figure.png

Description: Maximum likelihood phylogram of (A) genome and (B) plasmid sequences from clinical specimens assembled using C. trachomatis E/Bour reference. All branches had bootstrap values over 85/100

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