Follicular trachoma and trichiasis prevalence in an urban community in The Gambia, West Africa: is there a need to include urban areas in national trachoma surveillance?

Active trachoma and associated factors in children aged 1 to 9 years living in Sasiga rural districts, East Wallaga Zone, Ethiopia, in 2022: a community- based cross-sectional study

BACKGROUND

Trachoma, caused by the bacteria Chlamydia trachomatous, is a contagious eye condition that frequently affects children and quickly spreads from child to child and from child to caregiver. The study aimed to assess the distribution of active trachoma and its associated risk factors among children 1-9 years aged in Households of Sasiga Rural District, Western Ethiopia, in 2022.

METHODS

A community-based cross-sectional study was conducted among 577 randomly selected children from March to May 2022. A multistage sampling technique was used. Data was collected through an interviewer-based questionnaire, physical observation, and clinical eye examinations. Epi Data 3.1 was used for data entry. The data were analyzed with SPSS version 24. Bivariate and multivariate binary logistic regressions were performed. In multivariable logistic regression analysis, the adjusted odds ratio with a 95% confidence interval was used to identify factors associated with active trachoma. A P-value of 0.05 was considered statistically significant.

RESULTS

The distribution of Active Trachoma among children 1-9 years aged in Households of the study area was 9.5%(95%CI:7.11,11.89). Being from a low-income household with a monthly income of less than 1500 ETB [AOR = 3.49, 95% CI: 1.39, 8.75], Households where the nearest water supply is more than 30 min away [AOR = 8.34, 95%CI: 1.89, 36.73], households with only one room [AOR = 2.98, 95%CI: 1.027, 8.68], and presence of feces in the compound of the households [AOR = 3.08, 95%CI: 1.41, 6.75] were associated with active trachoma in 1-9 years aged children living in the study setting.

CONCLUSION

The distribution of Active Trachoma among children 1-9 years aged in Households of the study area was found to be high. Monthly income, the time it took to get water for home use, and the presence of feces in household compounds were all linked to active trachoma in children living in the study area. As a result, continuous sanitary education on trachoma transmission and prevention should be strengthened in the district.

Prevalence and associated factors of active trachoma among 1-9 years of age children in Andabet district, northwest Ethiopia, 2023: A multi-level mixed-effect analysis

BACKGROUND

Trachoma is the chief cause of preventable blindness worldwide and has been earmarked for elimination as a public health problem by 2030. Despite the five-year Surgery, Antibiotics, Facial cleanliness, and Environmental improvement (SAFE)-based interventions in the Andabet district, the prevalence of trachomatous follicular (TF) was 37%. With such a high prevalence of TF, the determinant factors were not revealed. Besides, there were no reports on the overall prevalence of active trachoma (i.e.TF and or trachomatous intense (TI)).

OBJECTIVE

To determine the prevalence and associated factors of active trachoma among 1-9 years of age children in the Andabet district.

METHOD

A community-based cross-sectional study was conducted among children aged under nine years from March 1-30, 2023 in Andabet district, Northwest Ethiopia. Multi-stage systematic random sampling was employed to reach 540 children. A multilevel mixed-effect logistic regression analysis was employed to assess factors associated with active trachoma. We fitted both random effect and fixed effect analysis. Finally, variables with p<0.05 in the multivariable multilevel analysis were claimed to be significantly associated with active trachoma.

RESULT

In this study, the overall prevalence of active trachoma was 35.37% (95% CI: 31.32%, 39.41%). The prevalence of TF and TI was 31.3% and 4.07% respectively. In the multilevel logistic regression analysis ocular discharge, fly-eye contact, latrine utilization, and source of water were significantly associated with the prevalence of active trachoma.

CONCLUSION

In this study, the prevalence of active trachoma was much higher than the World Health Organization (WHO) threshold prevalence. Ocular discharge, fly-eye contact, latrine utilization, and source of water were independent determinants of active trachoma among children (1-9 years). Therefore, paying special attention to these high-risk groups could decrease the prevalence of a neglected hyperendemic disease, active trachoma.

Prevalence of active trachoma and associated factors among children 1-9 years old at Arsi Negele Town, West Arsi Zone, Oromia Regional State, Southern Ethiopia

BACKGROUND

Trachoma is a public health issue in more than 50 nations worldwide, mainly in Sub-Saharan Africa, where hundreds of millions of people are considered blind. Ethiopia is projected to have 30% of the global active trachoma burden. The frequency of Trachoma Folliculitis in children aged 1 to 9 years old is 30% in the Oromia Region. Therefore, the aim of this study was to assess the prevalence of active trachoma and associated variables among children aged 1 to 9 years old in Arsi Negele Town, West Arsi Zone, Oromia Regional State, Southern Ethiopia, December 24-26, 2019.

METHODS

A community-based cross-sectional study was conducted in the Arsi Negele town community on December 24-26, 2019. A total of 178 study volunteers were recruited using a single population proportion formula and assigned to families in the town's three kebeles in proportion. A simple random selection procedure was used to choose study participants from the identified households. Madda Walabu University provided ethical approval, and different government structures provided letters of permission. Pre-tested structured questionnaires and binocular loupes X 2.5 were used to collect data from either mothers or fathers of eligible children for eye examination; torches with bottles of alcohol were used to gather data from either mothers or fathers of eligible children for eye examination. For analysis, data was entered into (IBM, SPSS) version 22. To assess factors associated with active trachoma, bivariate and multivariable logistic regressions were used. The crude and adjusted odds ratios with 95% confidence intervals were calculated to investigate the degree of association between the independent variables and active trachoma. Multivariate logistic regression was used to find connections between dependent and independent variables with a p≤ 0.05 confidence levels and a 95% confidence interval.

RESULT

The prevalence of active trachoma was determined to be 21.91% TF among 178 children aged 1 to 9 years. Flies on children's faces (AOR = 3.427; 95 percent CI: 1.432-8.171), unclean children's faces (AOR = 3.99; 95 percent CI: 1.427-11.158), face washing habits (AOR = 3.064; 95 percent CI: 1.273-7.373), and not using soap while face washing (AOR = 4.564; 95 percent CI 1.561-13.342) were found to be statistically significant associated factors with the prevalence of active trachoma.

CONCLUSION

The prevalence of active trachoma was found to be relatively high. Face washing practices and the lack of soap use while washing faces were found as associated factors requiring optimal interventions to prevent trachoma infection among children aged 1-9 years in Arsi Negele town.

Lessons learned for surveillance strategies for trachoma elimination as a public health problem, from the evaluation of approaches utilised by Guinea worm and onchocerciasis programmes: A literature review

Introduction

A number of neglected tropical diseases are targeted for elimination or eradication. An effective surveillance system is critical to determine if these goals have been achieved and maintained. Trachoma has two related but morphologically different presentations that are monitored for elimination, the active infectious form of trachoma and trachomatous trichiasis (TT), the progression of the disease. There are a number of lessons learnt from the Guinea worm surveillance system that are particularly compatible for TT surveillance and the onchocerciasis surveillance system which can provide insights for surveillance of the infectious form of trachoma.

Methods/Principal findings

A literature search of peer-reviewed published papers and grey literature was conducted using PUBMED and Google Scholar for articles relating to dracunculiasis or Guinea worm, onchocerciasis and trachoma, along with surveillance or elimination or eradication. The abstracts of relevant papers were read and inclusion was determined based on specified inclusion and exclusion criteria. The credibility and bias of relevant papers were also critically assessed using published criteria. A total of 41 papers were identified that were eligible for inclusion into the review.

The Guinea worm programme is designed around a surveillance-containment strategy and combines both active and passive surveillance approaches, with a focus on village-based surveillance and reporting. Although rumour reporting and a monetary incentive for the identification of confirmed Guinea worm cases have been reported as successful for identifying previously unknown transmission there is little unbiased evidence to support this conclusion. More rigorous evidence through a randomised controlled trial, influenced by motivational factors identified through formative research, would be necessary in order to consider applicability for TT case finding in an elimination setting. The onchocerciasis surveillance strategy focuses on active surveillance through sentinel surveillance of villages and breeding sites. It relies on an entomological component, monitoring infectivity rates of black flies and an epidemiological component, tracking exposure to infection in humans. Challenges have included the introduction of relatively complex diagnostics that are not readily available in onchocerciasis endemic countries and target thresholds, which are practically unattainable with current diagnostic tests. Although there is utility in monitoring for infection and serological markers in trachoma surveillance, it is important that adequate considerations are made to ensure evidence-based and achievable guidelines for their utility are put in place.

Conclusions/Significance

The experiences of both the Guinea worm and onchocerciasis surveillance strategies have very useful lessons for trachoma surveillance, pre- and post-validation. The use of a monetary reward for identification of TT cases and further exploration into the use of infection and serological indicators particularly in a post-validation setting to assist in identifying recrudescence would be of particular relevance. The next step would be a real-world evaluation of their relative applicability for trachoma surveillance.

The design of a surveillance system needs to be carefully thought out to ensure it provides sufficient evidence to determine if a disease or infection is eliminated or eradicated. If inappropriate it can lead to on-going transmission and resurgence of infection or disease or the unnecessary continuation of interventions, wasting valuable resources. Guinea worm is a disease that is painful and debilitating, for which there is no drug or vaccine. The aim is to eradicate the disease and as such the Guinea worm programme is designed around a strategy of identification of cases and their containment to prevent onward transmission. Onchocerciasis if left untreated can lead to blindness. The aim is to eliminate the disease through the interruption of transmission. A literature review was conducted to determine available evidence and identify lessons that can be learnt from the surveillance of both diseases for the design of trachoma surveillance strategies in the endgame. The potential utility of rumour reporting and a monetary incentive for the identification of a confirmed case of Guinea worm could be explored for trichiasis case finding. Trichiasis is the progression of trachoma and leads to significant ocular morbidity. The introduction of tests for infection and antibodies and the utility of sentinel surveillance as utilised for onchocerciasis are interesting considerations for active trachoma surveillance post-validation and has potential to identify recrudescence cost-effectively. The experiences of both the Guinea worm and onchocerciasis surveillance strategies have very useful lessons that can be trialled for trachoma surveillance. However, their real-world applicability and implications for trachoma need to be evaluated before any changes in guidelines are proposed.

The Relationship between Active Trachoma and Ocular Chlamydia trachomatis Infection before and after Mass Antibiotic Treatment

Background

Trachoma is a blinding disease, initiated in early childhood by repeated conjunctival infection with the obligate intracellular bacterium Chlamydia trachomatis. The population prevalence of the clinical signs of active trachoma; ‘‘follicular conjunctivitis” (TF) and/or ‘‘intense papillary inflammation” (TI), guide programmatic decisions regarding the initiation and cessation of mass drug administration (MDA). However, the persistence of TF following resolution of infection at both the individual and population level raises concerns over the suitability of this clinical sign as a marker for C. trachomatis infection.

Methodology/Principle Findings

We systematically reviewed the literature for population-based studies and those including randomly selected individuals, which reported the prevalence of the clinical signs of active trachoma and ocular C. trachomatis infection by nucleic acid amplification test. We performed a meta-analysis to assess the relationship between active trachoma and C. trachomatis infection before and after MDA. TF and C. trachomatis infection were strongly correlated prior to MDA (r = 0.92, 95%CI 0.83 to 0.96, p<0.0001); the relationship was similar when the analysis was limited to children. A moderate correlation was found between TI and prevalence of infection. Following MDA, the relationship between TF and infection prevalence was weaker (r = 0.60, 95%CI 0.25 to 0.81, p = 0.003) and there was no correlation between TI and C. trachomatis infection.

Conclusions/Significance

Prior to MDA, TF is a good indicator of the community prevalence of C. trachomatis infection. Following MDA, the prevalence of TF tends to overestimate the underlying infection prevalence. In order to prevent unnecessary additional rounds of MDA and to accurately ascertain when elimination goals have been reached, a cost-effective test for C. trachomatis that can be administered in low-resource settings remains desirable.

Trachoma is the leading infectious cause of blindness worldwide, caused by the bacterium Chlamydia trachomatis. Repeated infection of the conjunctiva during childhood can initiate chronic conjunctival inflammation. This can lead to conjunctival scarring, in turning of the eyelashes, abrasion of the eyelashes on the cornea and eventually blindness later in adulthood. The World Health Organization recommends mass drug administration (MDA) for infection control when the prevalence of the clinical sign of Active Trachoma (TF) is ≥10% in 1–9 year olds. This systematic review of the literature examined the relationship between TF and C. trachomatis infection before and after MDA in order to evaluate the usefulness of TF for guiding trachoma control programmes. The population prevalence of TF and C. trachomatis infection were strongly correlated prior to MDA, however the relationship was weaker after MDA with a greater tendency for TF to overestimate the underlying infection prevalence. A cost effective test for C. trachomatis suitable for use in low resource settings could prevent unnecessary additional rounds of MDA in the population and could identify when trachoma elimination goals have been reached at an earlier time point.

Cross-Sectional Surveys of the Prevalence of Follicular Trachoma and Trichiasis in The Gambia: Has Elimination Been Reached?

Background

The Gambia’s National Eye Health Programme has made a concerted effort to reduce the prevalence of trachoma. The present study had two objectives. The first was to conduct surveillance following mass drug administrations to determine whether The Gambia has reached the World Health Organization’s (WHO) criteria for trachoma elimination, namely a prevalence of trachomatous inflammation—follicular (TF) of less than 5% in children aged 1 to 9 years. The second was to determine the prevalence of trichiasis (TT) cases unknown to the programme and evaluate whether these meet the WHO criteria of less than 0.1% in the total population.

Methodology/Principal Findings

Three cross-sectional surveys were conducted between 2011 and 2013 to determine the prevalence of TF and TT in each of nine surveillance zones. Each zone was of similar size, with a population of 60,000 to 90,000, once urban settlements were excluded. Trachoma grading was carried out according to the WHO’s simplified trachoma grading system. The prevalence of TF in children aged 1 to 9 years was less than 5% in each surveillance zone at each of the three surveys. The prevalence of TT cases varied by zone from 0 to 1.7% of adults greater than 14 years while the prevalence of TT cases unknown to the country’s National Eye Health Programme was estimated at 0.15% total population.

Conclusions/Significance

The Gambia has reached the elimination threshold for TF in children. Further work is needed to bring the number of unknown TT cases below the elimination threshold.

Trachoma, the world’s leading infectious cause of blindness, is caused by ocular infection with the bacterium Chlamydia trachomatis. The Gambia, situated in West Africa, has implemented all facets of the World Health Organization-recommended SAFE strategy for trachoma control including surgery to correct the in-turning of eyelashes (trichiasis), mass drug administration with antibiotics, promotion of facial hygiene and environmental improvements. In 2011, The Gambia’s National Eye Health Programme began three years of rolling surveys to determine the prevalence of trachoma in the country and to evaluate whether trachoma elimination has been reached. The results suggest the country has reached the elimination threshold for trachoma in children (less than 5% prevalence) but that more work needs to be done to reduce the prevalence of trichiasis in adults.

Prevalence of Active Trachoma and Its Associated Factors among Rural and Urban Children in Dera Woreda, Northwest Ethiopia: A Comparative Cross-Sectional Study

Background. Trachoma is the most common infectious cause of blindness worldwide. Once an epidemic in most parts of the world, it has largely now disappeared from developed countries. However, it continues to be endemic in many developing countries like Ethiopia. Even if several studies were conducted in different parts of Ethiopia, most of them did not show the independent predictors for rural and urban children separately. Therefore, this study aimed at assessing the prevalence and associated factors of active trachoma in urban and rural children. Methods. Community based comparative cross-sectional study was conducted in Dera woreda. Multistage sampling technique was used to select 671 children of one up to nine years of age. Data were collected by face to face interview and observation using a structured and pretested questionnaire. Binary Logistic Regression Model was fitted to consider adding independent predictors of outcome. Results. Out of 671 children, 20 (9.3%) of urban and 85 (18.6%) of rural children were positive for active trachoma. Having discharge on eye (AOR = 6.9, 95% CI: 1.79–27.89), presence of liquid waste around the main house (AOR = 5.6, 95% CI: 1.94–16.18), and living in households without latrine (AOR = 4.39, 95% CI: 1.39–13.89) were significantly associated with active trachoma of urban children. Rural children who had discharge on their eye (AOR = 5.86, 95% CI: 2.78–12.33), those who had unclean face (AOR = 4.68, 95% CI: 2.24–9.81), and those living in households with feces around their main houses (AOR = 1.94, 95% CI: 1.04–3.62) were significantly associated with active trachoma. Conclusion. The result showed that the prevalence of active trachoma in urban areas of the district was below WHO threshold of 10% to determine trachoma as public health problem. However, in rural areas of the district it is far from elimination of trachoma as a public health problem. Thus, in order to improve awareness of the community there is a need of health education programs regarding facial cleanliness, utilization of latrine, and proper solid waste and liquid waste disposal using multidisciplinary approach.

Effect of water, sanitation, and hygiene on the prevention of trachoma: a systematic review and meta-analysis

BACKGROUND

Trachoma is the world's leading cause of infectious blindness. The World Health Organization (WHO) has endorsed the SAFE strategy in order to eliminate blindness due to trachoma by 2020 through "surgery," "antibiotics," "facial cleanliness," and "environmental improvement." While the S and A components have been widely implemented, evidence and specific targets are lacking for the F and E components, of which water, sanitation, and hygiene (WASH) are critical elements. Data on the impact of WASH on trachoma are needed to support policy and program recommendations. Our objective was to systematically review the literature and conduct meta-analyses where possible to report the effects of WASH conditions on trachoma and identify research gaps.

METHODS AND FINDINGS

We systematically searched PubMed, Embase, ISI Web of Knowledge, MedCarib, Lilacs, REPIDISCA, DESASTRES, and African Index Medicus databases through October 27, 2013 with no restrictions on language or year of publication. Studies were eligible for inclusion if they reported a measure of the effect of WASH on trachoma, either active disease indicated by observed signs of trachomatous inflammation or Chlamydia trachomatis infection diagnosed using PCR. We identified 86 studies that reported a measure of the effect of WASH on trachoma. To evaluate study quality, we developed a set of criteria derived from the GRADE methodology. Publication bias was assessed using funnel plots. If three or more studies reported measures of effect for a comparable WASH exposure and trachoma outcome, we conducted a random-effects meta-analysis. We conducted 15 meta-analyses for specific exposure-outcome pairs. Access to sanitation was associated with lower trachoma as measured by the presence of trachomatous inflammation-follicular or trachomatous inflammation-intense (TF/TI) (odds ratio [OR] 0.85, 95% CI 0.75-0.95) and C. trachomatis infection (OR 0.67, 95% CI 0.55-0.78). Having a clean face was significantly associated with reduced odds of TF/TI (OR 0.42, 95% CI 0.32-0.52), as were facial cleanliness indicators lack of ocular discharge (OR 0.42, 95% CI 0.23-0.61) and lack of nasal discharge (OR 0.62, 95% CI 0.52-0.72). Facial cleanliness indicators were also associated with reduced odds of C. trachomatis infection: lack of ocular discharge (OR 0.40, 95% CI 0.31-0.49) and lack of nasal discharge (OR 0.56, 95% CI 0.37-0.76). Other hygiene factors found to be significantly associated with reduced TF/TI included face washing at least once daily (OR 0.76, 95% CI 0.57-0.96), face washing at least twice daily (OR 0.85, 95% CI 0.80-0.90), soap use (OR 0.76, 95% CI 0.59-0.93), towel use (OR 0.65, 95% CI 0.53-0.78), and daily bathing practices (OR 0.76, 95% CI 0.53-0.99). Living within 1 km of a water source was not found to be significantly associated with TF/TI or C. trachomatis infection, and the use of sanitation facilities was not found to be significantly associated with TF/TI.

CONCLUSIONS

We found strong evidence to support F and E components of the SAFE strategy. Though limitations included moderate to high heterogenity, low study quality, and the lack of standard definitions, these findings support the importance of WASH in trachoma elimination strategies and the need for the development of standardized approaches to measuring WASH in trachoma control programs.