Distance to water source and altitude in relation to active trachoma in Rombo district, Tanzania

Photographic grading to evaluate facial cleanliness and trachoma among children in Amhara region, Ethiopia

BACKGROUND

Promotion of facial cleanliness is recommended for the elimination of blinding trachoma, largely because of observational studies that have found an association between various measures of facial uncleanliness and trachoma. However, when a field grader assesses both facial cleanliness and trachoma, associations may be biased. Assessment of photographs of the face and conjunctiva by masked graders may provide a less biased estimate of the relationship between facial cleanliness and trachoma.

METHODS

Face photographs, conjunctival photographs, and conjunctival swabs were obtained on a random sample of 0-9-year-old children from each of 40 communities in Amhara region, Ethiopia. Face photographs were assessed for the presence of seven measures of an unclean face (i.e., wet nasal discharge, dry nasal discharge, wet ocular discharge, dry ocular discharge, food, dust/dirt, and flies) by three independent masked photo-graders. Conjunctival photographs were similarly graded in a masked fashion for signs of clinically active trachoma. Conjunctival swabs were processed for Chlamydia trachomatis DNA.

RESULTS

Of 2073 children with complete data, 808 (39%) had evidence of clinically active trachoma, 150 (7%) had evidence of ocular chlamydia infection, and 2524 (91%) had at least one measure of an unclean face. Dry ocular discharge had the strongest association with clinically active trachoma (age- and sex-adjusted prevalence ratio [PR] 1.4, 95% CI 1.2-1.6) and ocular chlamydia infection (PR 1.9, 95%CI 1.3-2.9), although significant associations were observed between each of the measures of facial uncleanliness and trachoma.

CONCLUSIONS

Masked assessment of face and conjunctival photographs confirmed prior observational studies that have noted associations between various measures of facial uncleanliness and trachoma. The causal relationship between facial uncleanliness and trachoma is unclear since many features used to measure facial cleanliness (e.g., ocular discharge, nasal discharge, and flies) could be consequences of antecedent ocular chlamydia infection.

TRIAL REGISTRATION

NCT02754583, clinicaltrials.gov.

Eliminating Trachoma in Africa: The Importance of Environmental Interventions

Subsequent to the failure of the World Health Organisation (WHO) of achieving their target to eliminate trachoma by the year 2020, the most effective strategy in eliminating trachoma must be re-examined to accomplish the new target of eradication by the year 2030. Whilst antibiotic therapy is a core foundation of this elimination strategy, another important factor is the state of the environmental conditions in trachoma endemic countries. This manuscript aimed to identify the impact of environmental improvement strategies on the prevalence of trachoma and the significance of environmental improvement alongside the use of antibiotic treatment to achieve trachoma elimination. Two independent literature searches were conducted up until the 5th of July 2021. Two main databases were used to carry out these literature searches, namely, Ovid EMBASE and Ovid MEDLINE. All of the relevant references were found using MeSH and free text terms. Key terms used were 'trachoma', 'water', 'sanitation', 'hygiene' and 'environmental Improvement'. The exclusion criteria included non-African-based studies, review papers, protocols and case reports. A total of 17 studies were included for this review. Living within a close range of a water source was significantly associated with reduced risk of trachoma infection. Water obtained from piped water sources was associated with the lowest rates of active trachoma. Studies on facial cleanliness evidenced a strong association with reduced prevalence of trachoma. Whilst the provision of latrine facilities found was significantly associated with reduced prevalence of trachoma, there was no significant difference between the use of private latrine facilities over communal latrine facilities. The use of repeated scheduled antibiotic treatments over single-use antibiotic distribution had a greater impact both short term and long term on the prevalence rates of trachoma. Nonetheless, prevalence rates increased again following the commencement of treatment. Mass antibiotic treatment has been proven to have a greater impact on lowering the prevalence of trachoma initially, but this impact is not sustainable due to the rise in prevalence rates following the completion of treatment. A holistic approach, therefore, must be implemented with evidence showing that an emphasis on longer-term environmental methods should be implemented to compliment antibiotic distribution. Prioritisation of specific interventional measures should be tailored according to local epidemiology; nonetheless, these measures form the backbone of a trachoma elimination strategy to eliminate trachoma by the year 2030.

Determinants of Trachomatous Inflammation-Follicular Among Children Aged 1 to 9 Years Old in a Rural Area of Gozamn District, Northwestern Ethiopia: A Matched Case-Control Study

Background

Approximately 1.9 million people worldwide are blind or visually impaired due to trachoma, and trachoma remains endemic in 44 countries. Amhara in Ethiopia has the highest burden of trachoma in the world. A key indicator of whether active trachoma requires public health intervention is the incidence of trachomatous inflammation-follicular in children aged 1 to 9 years. However, limited study has been conducted on the determinants in rural communities. This study therefore aimed to fill this gap by identifying determinants in the Gozamn district of northwestern Ethiopia.

Methods

A community-based case-control study was carried out between March 15 and April 30, 2021. Five or more follicles on the epitaxial conjunctivae that are larger than 0.5 mm were considered a case. Controls were free of any sign of trachoma. A semi-structured questionnaire and an observational checklist were used to gather the data, and STATA version 14 was used for the analysis. Using a 95% confidence interval, both bivariable and multivariable conditional logistic regression was performed.

Results

A total of 726 mothers/caregivers participated in this study, with a participation rate of 98.4%. Children from poor families (mAOR = 4.68; CI: 2.80-6.21), households where the water source is far from home (>30 minutes) (mAOR = 4.91; KI: 1.37-12.56), mean daily water consumption (<20 l/c/d) (mAOR = 4.42; CI:1.71-11.39), face washing frequency less than once a day (mAOR = 10.64; CI: 2.58-18.84), cloth washing frequency once a month or less (mAOR = 9.18; CI: 2.20-18.62), and mothers or caregivers with poor knowledge of active trachoma (mAOR = 3.88; CI: 1.47-10.22) were determinants of trachomatous inflammation-follicular.

Conclusions

We conclude that infrequent faces and clothes washing; unavailability of water, children in poor families, and poor knowledge of mothers/caregivers were risk factors. Health education initiatives about active trachoma, its prevention, and control methods focusing on personal hygiene are so required.

Trachoma

Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectious-inflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individual's lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse.

Community-level trachoma ecological associations and the use of geospatial analysis methods: A systematic review

Background

Trachoma is targeted for global elimination as a public health problem by 2030. Understanding individual, household, or community-associated factors that may lead to continued transmission or risk of recrudescence in areas where elimination has previously been achieved, is essential in reaching and maintaining trachoma elimination. We aimed to identify climatic, demographic, environmental, infrastructural, and socioeconomic factors associated in the literature with trachoma at community-level and assess the strength of their association with trachoma. Because of the potential power of geospatial analysis to delineate the variables most strongly associated with differences in trachoma prevalence, we then looked in detail at geospatial analysis methods used in previous trachoma studies.

Methods

We conducted a systematic literature review using five databases: Medline, Embase, Global Health, Dissertations & Theses Global, and Web of Science, including publications from January 1950 to January 2021. The review protocol was prospectively registered with PROSPERO (CRD42020191718).

Results

Of 35 eligible studies, 29 included 59 different trachoma-associated factors, with eight studies also including spatial analysis methods. Six studies included spatial analysis methods only. Higher trachomatous inflammation—follicular (TF) prevalence was associated with areas that: had lower mean annual precipitation, lower mean annual temperatures, and lower altitudes; were rural, were less accessible, had fewer medical services, had fewer schools; and had lower access to water and sanitation. Higher trachomatous trichiasis (TT) prevalence was associated with higher aridity index and increased distance to stable nightlights. Of the 14 studies that included spatial methods, 11 used exploratory spatial data analysis methods, three used interpolation methods, and seven used spatial modelling methods.

Conclusion

Researchers and decision-makers should consider the inclusion and potential influence of trachoma-associated factors as part of both research activities and programmatic priorities. The use of geospatial methods in trachoma studies remains limited but offers the potential to define disease hotspots and areas of potential recrudescence to inform local, national, and global programmatic needs.

The ambitious target to eliminate trachoma as a public health problem has led to impressive strides in reducing the disease burden worldwide, with the implementation of the World Health Organization (WHO)-endorsed surgery, antibiotics, facial cleanliness and environmental improvement (SAFE) strategy. However, some areas have struggled to reach the elimination threshold after the prescribed number of antibiotic mass drug administration rounds, and some areas have had evidence of trachoma recrudescence after previously having reached the elimination threshold. This systematic review assessed climatic, demographic, environmental, infrastructural, and socioeconomic factors associated with trachoma to reveal which covariates are associated with ongoing or renewed trachoma transmission. We also explored how geospatial analysis, which could help identify areas with ongoing trachoma transmission or heightened risk of recrudescence, has been used in previous trachoma studies. Thirty-five studies met the inclusion criteria for the review. Results indicated that researchers and decision-makers should consider the inclusion and potential influence of precipitation, temperature, and altitude along with variables related to ruralness, accessibility, access to medical services and schools, and community-level water and sanitation coverage, as part of both research activities and programmatic priorities for trachoma elimination.

Predicting future community-level ocular Chlamydia trachomatis infection prevalence using serological, clinical, molecular, and geospatial data

Trachoma is an infectious disease characterized by repeated exposures to Chlamydia trachomatis (Ct) that may ultimately lead to blindness. Efficient identification of communities with high infection burden could help target more intensive control efforts. We hypothesized that IgG seroprevalence in combination with geospatial layers, machine learning, and model-based geostatistics would be able to accurately predict future community-level ocular Ct infections detected by PCR. We used measurements from 40 communities in the hyperendemic Amhara region of Ethiopia to assess this hypothesis. Median Ct infection prevalence among children 0–5 years old increased from 6% at enrollment, in the context of recent mass drug administration (MDA), to 29% by month 36, following three years without MDA. At baseline, correlation between seroprevalence and Ct infection was stronger among children 0–5 years old (ρ = 0.77) than children 6–9 years old (ρ = 0.48), and stronger than the correlation between active trachoma and Ct infection (0-5y ρ = 0.56; 6-9y ρ = 0.40). Seroprevalence was the strongest concurrent predictor of infection prevalence at month 36 among children 0–5 years old (cross-validated R2 = 0.75, 95% CI: 0.58–0.85), though predictive performance declined substantially with increasing temporal lag between predictor and outcome measurements. Geospatial variables, a spatial Gaussian process, and stacked ensemble machine learning did not meaningfully improve predictions. Serological markers among children 0–5 years old may be an objective tool for identifying communities with high levels of ocular Ct infections, but accurate, future prediction in the context of changing transmission remains an open challenge.

Status of active trachoma infection among school children who live in villages of open field defecation: a comparative cross-sectional study

BACKGROUND

Although many efforts are made by different stakeholders, magnitude of active trachoma remains high among children in Ethiopia. Open field defecation was found to be the main source of active trachoma. However, comparative information on the effect of open field defecation and non-open field defecation on active trachoma is scarce in Ethiopia.

METHODS

Comparative community based cross-sectional study was conducted from June 1-30, 2019 in Boricha and Dale districts to assess prevalence of active trachoma among primary school children. We have selected four primary schools purposively from two districts in Sidama. Study participants were selected by using simpe random sampling method. Data were collected through face to face interview, direct observation and ophthalmic examination. Logistic regression analysis was conducted to assess factors associated with active trachoma infection among primary school children. Adjusted Odds Ratios with 95% confidence interval and p-value less than 0.05 were computed to determine the level of significance.

RESULT

From the total of 746 study participants, only 701 study participants gave full response for interview questions making a response rate of 94%. The overall prevalence of active trachoma infection was 17.5% (95% CI, 14.1-20.8) among primary school students. Specifically, prevalence of active trachoma infection was 67.5% among children who lived in open field defecation villages, but it was 88.5% among school children who live in Non-ODF Kebeles. Factors like: Living in open field defecation Kebeles (AOR = 2.52, 95% CI, 1.5-4.1), having ocular discharge (AOR = 5.715, 95% CI, 3.4-9.4), having nasal discharge (AOR = 1.9, 95% CI, 1.06-3.39), and fly on the face (AOR = 6.47, 95% CI, 3.36-12.44) of children were positively associated with active trachoma infection. However, finger cleanness (AOR = 0.43, 95% CI, 0.21-0.9) was protective factor against active trachoma infection in this study.

CONCLUSION

Significant variation in prevalence of active trachoma infection among school children between open filed and non-open field defecation Kebeles was observed. Surprisingly, the prevalence in open field defecation was significantly lower than non-open field defecation. Hence, this indicates active trachoma infection highly depends on the hand hygiene than environmental sanitation. Educational campaign of hand hygiene should be enhanced in the community for school students.

Ocular microbial diversity, community structure, and function at high altitude

PURPOSE

To investigate the composition and function of ocular surface microbiome in healthy people from different altitudes.

METHODS

Thirty-two healthy people living in a high altitude region and 30 sex- and age-matched individuals living in a low altitude region were enrolled. Samples were collected from the lower conjunctival sac of one randomly chosen eye for each participant. 16S rRNA sequencing was conducted to study the bacterial community composition and predict gene function using PICRUSt software.

RESULTS

Microbial diversity and richness was significantly decreased in samples from highlanders as calculated by Abundance-based Coverage Estimator (ACE) index, Chao1 index, and observed-species index (all p < 0.01). Principle coordinate analysis (PCoA) suggested significantly distinct clustering of the conjunctival sac bacterial communities between two groups (p = 0.03), especially the dominant genera. The relative abundances of Corynebacterium, Staphylococcus, and Anaerococcus were significantly enriched in highlanders, while those of Pseudomonas and Massilia were significantly decreased as compared with lowlanders (p < 0.01). In the functional annotation analysis, we found that 74 gene pathways, mainly in metabolism, differed in abundance. Pathways related to immune system diseases and infectious diseases were also enriched in highlanders.

CONCLUSION

The composition and function of ocular surface microbiome in highlanders were distinct from those of lowlanders and our study may provide a reference catalog of the healthy conjunctival microbiome in highlanders.

The impact of access to water supply and sanitation on the prevalence of active trachoma in Ethiopia: A systematic review and meta-analysis

Background

Trachoma is a worldwide infectious disease causing blindness. Trachoma continued as a public health problem in Ethiopia due to a lack of sanitation and inadequate prevention strategies. This study aimed to identify the impact of water supply and sanitation intervention on preventing active trachoma among children.

Methods

Systematic literature searches were performed from 4 international databases. The search involved articles published from January 1995 up to March 2019. The Cochran Q and I² statistical tests were used to check heterogeneity among the studies. A random-effect meta-analysis was employed to determine the pooled estimates with a 95% confidence interval (CI). Data analysis was performed using the CMA V.3 and RevMan 5 software program, and the result of the systematic review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Findings

Out of 211 studies screened for the analysis, only 29 studies were finally included in this systematic review and meta-analysis. The result revealed factors that are significantly associated with increased odds of active trachoma. Accordingly, households with no access to toilet facilities (odds ratio [OR]: 2.04, 95% CI: 1.75–2.38), no access to improved water (OR: 1.58, 95% CI: 1.27–1.96), and do not practice regular face washing for children (OR: 4.19, 95% CI: 3.02–5.81) have shown increased odds of active trachoma. Besides, the results show a higher prevalence of active trachoma among children who did not wash their faces with soap and frequently.

Conclusions

The study found strong evidence that lack of access to water, sanitation, and hygiene (WASH) was associated with increased prevalence of active trachoma among children. Therefore, a comprehensive and partnership-oriented program is needed to tackle the problem, but further study will be required to strengthen its implementation.

Prevalence and associated factors of active trachoma among children in Ethiopia: a systematic review and meta-analysis

BACKGROUND

Trachoma is the commonest infectious cause of blindness. It is prevalent in areas where personal and community hygiene is poor, and it mainly affects deprived and marginalized communities most importantly in Ethiopia. Hence, the aim of this study was to determine the prevalence and associated factors of active trachoma among children in Ethiopia.

METHOD

A systematic review and meta-analysis was employed to determine the prevalence of active trachoma and associated factors among children in Ethiopia. We searched databases, including PubMed, Google Scholar, Science Direct, EMBASE and Cochrane Library. To estimate the prevalence, studies reporting the prevalence of active trachoma and its associated factors were included. Data were extracted using a standardized data extraction format prepared in Microsoft excel and the analysis was done using STATA 14 statistical software. To assess heterogeneity, the Cochrane Q test statistics and I² test were used. Since the included studies revealed considerable heterogeneity, a random effect meta- analysis model was used to estimate the pooled prevalence of active trachoma. Moreover, the association between factors and active trachoma were examined.

RESULTS

The result of 30 eligible studies showed that the overall prevalence of active trachoma among children in Ethiopia was 26.9% (95% CI: 22.7, 31.0%). In the subgroup analysis, while the highest prevalence was reported in SNNP (35.8%; 95% CI: 22.7, 48.8), the lowest prevalence was reported in Oromia region (20.2%; 95% CI: 12.2, 28.2). Absence of latrine: OR 6.0 (95% CI 2.0, 17.5), the unclean faces of children: OR 5.5 (95% CI 2.8, 10.9), and no reported use of soap for washing: OR 3.3 (95% CI 1.8, 6.0) have shown a positive association with active trachoma among children.

CONCLUSION

From this review, it has been concluded that active trachoma among children is still a public health problem in different districts of Ethiopia. The prevalence of almost all studies are significantly higher than WHO target for elimination. Absence of latrine, unclean faces of children, no reported use of soap for washing are the important factors associated with active trachoma among children.

Unimproved water sources and open defecation are associated with active trachoma in children in internally displaced persons camps in the Darfur States of Sudan

PURPOSE

To estimate the proportion of children with trachomatous inflammation-follicular (TF) and adults with trachomatous trichiasis (TT) in internally displaced persons (IDP) camps in the Darfur States of Sudan and to evaluate associated risk factors.

METHODS

IDP camps were identified from government census data. We conducted a subanalysis of data collected in these camps during 2014-2015 as part of surveys covering 37 districts of the Darfur States within the Global Trachoma Mapping Project. A random-effects hierarchical model was used to evaluate factors associated with TF in children or TT in adults.

RESULTS

Thirty-six IDP camps were represented in the survey data, in which 1926 children aged 1-9 y were examined, of whom 38 (8%) had TF. Poor sanitation, younger age and living in a household that purchased water from a vendor were associated with TF in children aged 1-9 y. Of 2139 individuals examined aged ≥15 y, 16 (0.7%) had TT. TT was strongly independently associated with being older and living alone.

CONCLUSION

Trachoma is found at low levels in these camps, but still at levels where intervention is needed. Disease elimination in conflict-related settings presents a unique challenge for the trachoma community, and may require an innovative approach. Understanding how best to undertake trachoma elimination interventions in these areas should be prioritized.

Understanding the spatial distribution of trichiasis and its association with trachomatous inflammation-follicular

BACKGROUND

Whilst previous work has identified clustering of the active trachoma sign "trachomatous inflammation-follicular" (TF), there is limited understanding of the spatial structure of trachomatous trichiasis (TT), the rarer, end-stage, blinding form of disease. Here we use community-level TF prevalence, information on access to water and sanitation, and large-scale environmental and socio-economic indicators to model the spatial variation in community-level TT prevalence in Benin, Cote d'Ivoire, DRC, Guinea, Ethiopia, Malawi, Mozambique, Nigeria, Sudan and Uganda.

METHODS

We fit binomial mixed models, with community-level random effects, separately for each country. In countries where spatial correlation was detected through a semi-variogram diagnostic check we then fitted a geostatistical model to the TT prevalence data including TF prevalence as an explanatory variable.

RESULTS

The estimated regression relationship between community-level TF and TT was significant in eight countries. We estimate that a 10% increase in community-level TF prevalence leads to an increase in the odds for TT ranging from 20 to 86% when accounting for additional covariates.

CONCLUSION

We find evidence of an association between TF and TT in some parts of Africa. However, our results also suggest the presence of additional, country-specific, spatial risk factors which modulate the variation in TT risk.

Prevalence of active trachoma and associated risk factors among children of the pastoralist population in Madda Walabu rural district, Southeast Ethiopia: a community-based cross-sectional study

BACKGROUND

In developing countries particularly in sub-Saharan Africa trachoma is still a public health concern. Ethiopia is the most affected of all and bears the highest burden of active trachoma. In spite of this, the prevalence of active trachoma among the pastoralist population in Ethiopia not yet disclosed. The aim of this study was to determine the prevalence of active trachoma and associated risk factors among children in a pastoralist population in Madda Walabu rural district, Ethiopia.

METHODS

A community-based cross-sectional study was conducted among children in a pastoralist population in Madda Walabu rural district, from May 1 to 30, 2017. A systematic sampling technique was employed to select 409 children's. Simplified WHO classification scheme was used to assess trachoma. Descriptive and logistic regression analyses were performed.

RESULTS

A total of 406 children aged 1-9 years have participated, 89 (22%) [95%CI: 18.0-25.6%] were positive for active trachoma. Of these cases, 75(84%) had TI alone in one or both eyes, 14(16%) had TF alone in one or both eyes, and none of the children had both TI and TF. The odds of having active trachoma among children from households using river/ponds, unprotected well/spring and rainwater as their source of drinking water were higher than those from households using water from piped or public tap water (AOR:13,95%CI: 2.9, 58.2), (AOR: 6.1, 95%CI:1.0,36.5) and (AOR: 4.8, 95%CI:1.3,17.8) respectively. Children's from households that lacked a latrine (AOR: 2.5, 95% CI: 1.8, 5.3), children who did not wash their face by using soap (AOR: 4.3, 95% CI: 1.8, 10.6) and children from households within 16-30 min of water source (AOR: 8.7, 95% CI: 2.20, 34.2) were higher odds of having active trachoma.

CONCLUSIONS

The findings of this study revealed that close to one-quarter of the total children screened for trachoma were positive for the disease. The finding implies that trachoma is still a major concern among children of the pastoralist community which demands further attention of the district health office. Again, intervention with the A, F and E components of SAFE strategy is strongly recommended.

Cross-sectional Survey on Antibiotic Prescription Practices Among Health Care Providers in Rombo District, Northern Tanzania

Background:

Irrational and inappropriate antibiotic prescription is a worldwide phenomenon – increasing the threat of serious antibiotic resistance. A better understanding of health care providers' knowledge, attitudes, and prescription practices related to antibiotics is essential for formulating effective antibiotics stewardship programmes. The aim of the present study was to assess knowledge, attitudes, and prescription practices toward antibiotics among health care providers.

Methods:

A descriptive cross-sectional study was conducted between March and June 2017 to assess knowledge, attitudes, and prescription practices toward antibiotics among health care providers in the Rombo district of northern Tanzania. A total of 217 health care providers were interviewed using a structured questionnaire.

Results:

Over half of health care providers (n=111, 51.2%) strongly agreed that the inappropriate prescription of antibiotics puts patients at risk. More than half (n=112, 51.6%) reported that their decision to start antibiotic therapy was influenced by a patient's clinical condition, while 110 (50.7%) reported they were influenced by positive microbiological results in symptomatic patients. Almost two-thirds of the health care providers (n=136, 62.7%) reported that they had access to and used antibiotic therapy guidelines. Less than a quarter (n=52, 24.0%) received regular training and education in antibiotic prescription practice in their work place.

Conclusion:

Knowledge and prescription practice of antibiotics among health care providers was generally unsatisfactory. Training and education for health care providers is needed in the area of prescribing antibiotics.

The burden of and risk factors for active trachoma in the North and South Wollo Zones of Amhara Region, Ethiopia: a cross-sectional study

BACKGROUND

Trachoma is a disease of the eye, caused by the bacteria Chlamydia trachomatis, which can lead to blindness if left untreated. Ethiopia is one of the most trachoma-affected countries in the world. The objective of this study was to determine the prevalence of and associated risk factors for active trachoma among children in selected woredas of North and South Wollo Zones in Amhara Region, Ethiopia.

METHODS

This study was a community-based, cross-sectional study, which was conducted from October to December 2014 among children aged 1-8. A four-stage random cluster sampling technique was employed to select the study areas and participants. From each selected household, one child was clinically assessed for active trachoma. A structured questionnaire was used to collect sociodemographic, behavioral, and clinical data. Multivariate logistic regression analysis was used to analyze the association between predictor variables and active trachoma.

RESULTS

The overall prevalence of active trachoma among 1358 children was found to be 21.6% (95% CI: 19.4-23.8%). When analyzed by the presence or absence of individual WHO simplified system signs of active trachoma, trachomatous inflammation-follicular cases constituted18% (95% CI: 15.9-20.2%), while 4.7% (95% CI: 3.6-5.8%) were trachomatous inflammation-intense cases. Ocular discharge (aOR = 5.2; 95% CI: 3.3-8.2), nasal discharge (aOR = 1.8; 95% CI: 1.2-2.7), time taken to fetch water (aOR = 0.02; 95% CI: 0.01-0.05), frequency of hand and face washing (aOR = 4.4; 95% CI: 1.1-17.8), and access to a latrine (aOR = 0.006; 95% CI: 0.001-0.030) were found to be independently associated with the presence of active trachoma.

CONCLUSIONS

There is a high burden of active trachoma among children in the study areas. Lack of personal hygiene and limited access to a safe water supply and latrines were associated with increased prevalence of active trachoma. In order to reduce the burden of active trachoma, facial cleanliness and environmental improvement components of the SAFE strategy should be upgraded in the study areas.

Prevalence and determinants of active trachoma among preschool-aged children in Dembia District, Northwest Ethiopia

Background

Trachoma is an infectious eye disease caused by Chlamydia trachomatis, which is the leading infectious cause of blindness worldwide. In areas where trachoma is endemic, active trachoma is common among preschool-aged children, with varying magnitude. This study aimed to estimate the prevalence of active trachoma and associated risk factors among preschool-aged children in Dembia District, northwest Ethiopia.

Methods

A community-based cross-sectional survey was conducted among preschool-aged children of northwest Ethiopia. Multistage systematic random sampling was used to select 695 subjects. Trained clinical optometrists subjected each child to an ocular examination and assessed the presence of active trachoma. Face to face interview using pretested and structured questionnaire were conducted to collect data on possible risk factors. Trachoma cases were graded following a World Health Organization simplified grading scheme. All statistical analysis was carried out using the SPSS software version 20. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were used to identify factors associated with active trachoma.

Results

Of the 681 preschool-aged children studied, 18% (95% CI: 15.4% – 21.1%) had a prevalence of active trachoma. Children who had clean faces (absence of nasal and ocular discharges) had a lower chance of having active trachoma [aOR = 0.55, 95% CI: 0.37 – 0.82]. The odds of having active trachoma decreased with an increase in the distance to a water point [aOR = 0.51, 95% CI: 0.33 – 0.78]. Similarly, no or poor utilization of liquid waste disposal in the child’s household was associated with an increased chance of having active trachoma [aOR = 3.83, 95% CI: 1.26 – 11.61].

Conclusion

The prevalence of active trachoma in these preschool-aged children was found to be high and needs special interventions that focus on educating families about proper face washing, liquid waste disposal, and improving safe water supply near the households.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0345-8) contains supplementary material, which is available to authorized users.

Prevalence of and Risk Factors for Trachoma in Oromia Regional State of Ethiopia: Results of 79 Population-Based Prevalence Surveys Conducted with the Global Trachoma Mapping Project

PURPOSE

To complete the baseline trachoma map in Oromia, Ethiopia, by determining prevalences of trichiasis and trachomatous inflammation - follicular (TF) at evaluation unit (EU) level, covering all districts (woredas) without current prevalence data or active control programs, and to identify factors associated with disease.

METHODS

Using standardized methodologies and training developed for the Global Trachoma Mapping Project, we conducted cross-sectional community-based surveys from December 2012 to July 2014.

RESULTS

Teams visited 46,244 households in 2037 clusters from 252 woredas (79 EUs). A total of 127,357 individuals were examined. The overall age- and sex-adjusted prevalence of trichiasis in adults was 0.82% (95% confidence interval, CI, 0.70-0.94%), with 72 EUs covering 240 woredas having trichiasis prevalences above the elimination threshold of 0.2% in those aged ≥15 years. The overall age-adjusted TF prevalence in 1-9-year-olds was 23.4%, with 56 EUs covering 218 woredas shown to need implementation of the A, F and E components of the SAFE strategy (surgery, antibiotics, facial cleanliness and environmental improvement) for 3 years before impact surveys. Younger age, female sex, increased time to the main source of water for face-washing, household use of open defecation, low mean precipitation, low mean annual temperature, and lower altitude, were independently associated with TF in children. The 232 woredas in 64 EUs in which TF prevalence was ≥5% require implementation of the F and E components of the SAFE strategy.

CONCLUSION

Both active trachoma and trichiasis are highly prevalent in much of Oromia, constituting a significant public health problem for the region.

'If an Eye Is Washed Properly, It Means It Would See Clearly': A Mixed Methods Study of Face Washing Knowledge, Attitudes, and Behaviors in Rural Ethiopia

BACKGROUND

Face cleanliness is a core component of the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvements) strategy for trachoma control. Understanding knowledge, attitudes, and behaviors related to face washing may be helpful for designing effective interventions for improving facial cleanliness.

METHODS

In April 2014, a mixed methods study including focus groups and a quantitative cross-sectional study was conducted in the East Gojjam zone of the Amhara region of Ethiopia. Participants were asked about face washing practices, motivations for face washing, use of soap (which may reduce bacterial load), and fly control strategies.

RESULTS

Overall, both knowledge and reported practice of face washing was high. Participants reported they knew that washing their own face and their children's faces daily was important for hygiene and infection control. Although participants reported high knowledge of the importance of soap for face washing, quantitative data revealed strong variations by community in the use of soap for face washing, ranging from 4.4% to 82.2% of households reporting using soap for face washing. Cost and forgetfulness were cited as barriers to the use of soap for face washing. Keeping flies from landing on children was a commonly cited motivator for regular face washing, as was trachoma prevention.

CONCLUSIONS

Interventions aiming to improve facial cleanliness for trachoma prevention should focus on habit formation (to address forgetfulness) and address barriers to the use of soap, such as reducing cost. Interventions that focus solely on improving knowledge may not be effective for changing face-washing behaviors.

A Cross-Sectional Population-Based Survey of Trachoma among Migrant School Aged Children in Shanghai, China

We investigated the prevalence of clinical trachoma in 154,265 children aged 6 to 16 years in 206 Shanghai migrant schools. Clean water availability in school, each child's facial cleanliness, eyelids, corneas, and the presenting distance visual acuities were examined. Trachoma was clinically diagnosed in accordance with the World Health Organization simplified classification. Eyes diagnosed with trachoma were swabbed to test for ocular Chlamydia trachomatis infections (OCTI) with a rapid latex immunochromatographic test. Among 153,977 students, no blindness was found related to trachoma. Trachoma was diagnosed in 8029 children (5.2%). In 87 schools clinical trachoma prevalence was higher than 5%. OCTI was confirmed in 2073 of 6823 trachoma diagnosed children (30.4%). Clinical trachoma prevalence was higher among females than males (p < 0.001), but gender comparison showed no statistical difference in the prevalence of OCTI (p = 0.077). Age and clinical trachoma (r = -0.014; p < 0.001) or OCTI (r = -0.026; p = 0.031) prevalence were negatively correlated. Clinical trachoma was different in different districts and counties (p < 0.001). Trachoma warrants close attention in Shanghai migrant children because the condition remains endemic in some schools.

Rural children active trachoma risk factors and their interactions

Introduction

Trachoma is a serious public health problem in rural Ethiopia. The aim of this investigation was to provide in-depth statistical analysis of the risk factors associated with active trachoma among children of age 1-9 years of Kedida Gamela district, in Ethiopia.

Methods

A community based cross-sectional survey of trachoma was conducted in six selected rural kebeles of Kedida Gamela district, in Ethiopia from June 10-25, 2014. A total of 377 children (ages 1-9 years) were included in the study using two stage cluster sampling. All children were examined for trachoma by nurse data collectors supervised by ophthalmic supervisors using the WHO simplified clinical grading system. Ordinal survey logistic regression model was used to identify risk factors. Data analysis was done using SAS version 9.3.

Results

The best fit proportional odds model was identified to be the main effects and two-way and three-way interactios. Keeping cattle in the house was found to have a protective effect (OR=0.138, p-value=0.0003). The household wealth will have a more protective effect if the child attends school. Washing face with soap and water once a day has equivalent protective effect as washing face three-or-more times a day with water only.

Conclusion

The 2-way and 3-way significant interactions effects unfolded some of the controversies derived from similar studies on trachoma risk factors. The findings would suggest integrated effort to address two or three factors simultaneously is more fruitful than any novel intervention targeted to address a single risk factor.

Multilevel Analysis of Trachomatous Trichiasis and Corneal Opacity in Nigeria: The Role of Environmental and Climatic Risk Factors on the Distribution of Disease

The distribution of trachoma in Nigeria is spatially heterogeneous, with large-scale trends observed across the country and more local variation within areas. Relative contributions of individual and cluster-level risk factors to the geographic distribution of disease remain largely unknown. The primary aim of this analysis is to assess the relationship between climatic factors and trachomatous trichiasis (TT) and/or corneal opacity (CO) due to trachoma in Nigeria, while accounting for the effects of individual risk factors and spatial correlation. In addition, we explore the relative importance of variation in the risk of trichiasis and/or corneal opacity (TT/CO) at different levels. Data from the 2007 National Blindness and Visual Impairment Survey were used for this analysis, which included a nationally representative sample of adults aged 40 years and above. Complete data were available from 304 clusters selected using a multi-stage stratified cluster-random sampling strategy. All participants (13,543 individuals) were interviewed and examined by an ophthalmologist for the presence or absence of TT and CO. In addition to field-collected data, remotely sensed climatic data were extracted for each cluster and used to fit Bayesian hierarchical logistic models to disease outcome. The risk of TT/CO was associated with factors at both the individual and cluster levels, with approximately 14% of the total variation attributed to the cluster level. Beyond established individual risk factors (age, gender and occupation), there was strong evidence that environmental/climatic factors at the cluster-level (lower precipitation, higher land surface temperature, higher mean annual temperature and rural classification) were also associated with a greater risk of TT/CO. This study establishes the importance of large-scale risk factors in the geographical distribution of TT/CO in Nigeria, supporting anecdotal evidence that environmental conditions are associated with increased risk in this context and highlighting their potential use in improving estimates of disease burden at large scales.

Trichiasis (TT) and corneal opacity (CO) are chronic stages of trachoma, which remains an important cause of blindness. This study used multilevel spatial models to investigate risk factors for TT/CO in Nigeria, including data for more than 13,500 adults aged 40 years and above collected in the 2007 National Blindness and Visual Impairment survey. Individual-level risk factors were consistent with those identified in other studies, including a higher risk in females, older individuals and those with lower socioeconomic status. After controlling for these factors, there was evidence that a number of environmental and climatic factors are associated with the distribution of TT/CO in Nigeria. These findings establish for the Nigerian context the importance of risk factors at different scales for the later stages of trachoma, supporting anecdotal evidence that hotter, drier environmental conditions are associated with increased risk.

Risk factors for active trachoma and ocular Chlamydia trachomatis infection in treatment-naïve trachoma-hyperendemic communities of the Bijagós Archipelago, Guinea Bissau

BACKGROUND

Trachoma, caused by ocular infection with Chlamydia trachomatis, is hyperendemic on the Bijagós Archipelago of Guinea Bissau. An understanding of the risk factors associated with active trachoma and infection on these remote and isolated islands, which are atypical of trachoma-endemic environments described elsewhere, is crucial to the implementation of trachoma elimination strategies.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional population-based trachoma prevalence survey was conducted on four islands. We conducted a questionnaire-based risk factor survey, examined participants for trachoma using the World Health Organization (WHO) simplified grading system and collected conjunctival swab samples for 1507 participants from 293 randomly selected households. DNA extracted from conjunctival swabs was tested using the Roche Amplicor CT/NG PCR assay. The prevalence of active (follicular and/or inflammatory) trachoma was 11% (167/1508) overall and 22% (136/618) in 1-9 year olds. The prevalence of C. trachomatis infection was 18% overall and 25% in 1-9 year olds. There were strong independent associations of active trachoma with ocular and nasal discharge, C. trachomatis infection, young age, male gender and type of household water source. C. trachomatis infection was independently associated with young age, ocular discharge, type of household water source and the presence of flies around a latrine.

CONCLUSIONS/SIGNIFICANCE

In this remote island environment, household-level risk factors relating to fly populations, hygiene behaviours and water usage are likely to be important in the transmission of ocular C. trachomatis infection and the prevalence of active trachoma. This may be important in the implementation of environmental measures in trachoma control.

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.

School-Based Intervention: Evaluating the role of Water, Latrines and Hygiene Education on Trachoma and Intestinal Parasitic Infections in Ethiopia

OBJECTIVE

We sought to evaluate the impact of a hygiene and sanitation intervention program among school-children to control active trachoma and intestinal parasitic infections.

METHODS

This longitudinal epidemiologic study was conducted among 630 students in rural Ethiopia. Baseline and follow-up surveys were conducted to evaluate the impact of a three pronged intervention program i) constructing of ventilated improved pit latrines, ii) provision of clean drinking water, and iii) and hygiene education. Socio-demographic information was collected using a structured questionnaire. Presence of trachoma and intestinal parasitic infections were evaluated using standard procedures.

RESULTS

At baseline 15% of students had active trachoma while 6.7% of them were found to have active trachoma post intervention (p<0.001). Similar improvements were noted for parasitic infections. At baseline 7% of students were reported to have helminthic infections and 30.2% protozoa infections. However, only 4% of students had any helminthic infection and 13.4% (p<0.001) of them were found to have any protozoa infection. Improvements were noted in students' knowledge and attitudes towards hygiene and sanitation.

CONCLUSIONS

The results of our study demonstrated that provision of comprehensive and targeted sanitation intervention program was successful in reducing the burden of trachoma and intestinal parasitic infection among school children.

The impact of climatic risk factors on the prevalence, distribution, and severity of acute and chronic trachoma

BACKGROUND AND OBJECTIVES

Trachoma is the most common cause of infectious blindness. Hot, dry climates, dust and water scarcity are thought to be associated with the distribution of trachoma but the evidence is unclear. The aim of this study was to evaluate the epidemiological evidence regarding the extent to which climatic factors explain the current prevalence, distribution, and severity of acute and chronic trachoma. Understanding the present relationship between climate and trachoma could help inform current and future disease elimination.

METHODS

A systematic review of peer-reviewed literature was conducted to identify observational studies which quantified an association between climate factors and acute or chronic trachoma and which met the inclusion and exclusion criteria. Studies that assessed the association between climate types and trachoma prevalence were also reviewed.

RESULTS

Only eight of the 1751 papers retrieved met the inclusion criteria, all undertaken in Africa. Several papers reported an association between trachoma prevalence and altitude in highly endemic areas, providing some evidence of a role for temperature in the transmission of acute disease. A robust mapping study found strong evidence of an association between low rainfall and active trachoma. There is also consistent but weak evidence that the prevalence of trachoma is higher in savannah-type ecological zones. There were no studies on the effect of climate in low endemic areas, nor on the effect of dust on trachoma.

CONCLUSION

Current evidence on the potential role of climate on trachoma distribution is limited, despite a wealth of anecdotal evidence. Temperature and rainfall appear to play a role in the transmission of acute trachoma, possibly mediated through reduced activity of flies at lower temperatures. Further research is needed on climate and other environmental and behavioural factors, particularly in arid and savannah areas. Many studies did not adequately control for socioeconomic or environmental confounders.

Rapid assessment of trachoma in underserved population of Car-Nicobar Island, India

PURPOSE

To determine the burden of trachoma and its related risk factors amongst the native population of Car-Nicobar Island in India.

METHODS

Rapid assessment for trachoma was conducted in ten villages of Car-Nicobar Island according to standard WHO guidelines. An average of 50 children aged 1-9 years were assessed clinically for signs of active trachoma and facial cleanliness in each village. Additionally, all adults above 15 years of age in these households were examined for evidence of trachomatous trichiasis and corneal opacity. Environmental risk factors contributing to trachoma like limited access to potable water & functional latrine, presence of animal pen and garbage within the Nicobari hut were also noted in all villages.

RESULTS

Out of a total of fifteen villages in Car-Nicobar Island, ten villages were selected for trachoma survey depending on evidence of socio-developmental indicators like poverty and decreased access to water, sanitation and healthcare facilities. The total population of the selected clusters was 7277 in the ten villages. Overall, 251 of 516 children (48.6%;CI: 46.5-55.1) had evidence of follicular stage of trachoma and 11 children (2.1%;CI:1.0-3.4) had evidence of inflammatory stage of trachoma. Nearly 15%(CI:12.1-18.3) children were noted to have unclean faces in the ten villages. Trachomatous trichiasis was noted in 73 adults (1.0%;CI:0.8-1.2). The environmental sanitation was not found to be satisfactory in the surveyed villages mainly due to the co-habitance of Nicobari people with domestic animals like pigs, hens, goats, dogs, cats etc in most (96.4%) of the households.

CONCLUSION

Active trachoma and trachomatous trichiasis was observed in all the ten villages surveyed, wherein trachoma control measures are needed.

The effectiveness of public health interventions to reduce the health impact of climate change: a systematic review of systematic reviews

BACKGROUND

Climate change is likely to be one of the most important threats to public health in the coming years. Yet despite the large number of papers considering the health impact of climate change, few have considered what public health interventions may be of most value in reducing the disease burden. We aimed to evaluate the effectiveness of public health interventions to reduce the disease burden of high priority climate sensitive diseases.

METHODS AND FINDINGS

For each disease, we performed a systematic search with no restriction on date or language of publication on Medline, Web of Knowledge, Cochrane CENTRAL and SCOPUS up to December 2010 to identify systematic reviews of public health interventions. We retrieved some 3176 records of which 85 full papers were assessed and 33 included in the review. The included papers investigated the effect of public health interventions on various outcome measures. All interventions were GRADE assessed to determine the strength of evidence. In addition we developed a systematic review quality score. The interventions included environmental interventions to control vectors, chemoprophylaxis, immunization, household and community water treatment, greening cities and community advice. For most reviews, GRADE showed low quality of evidence because of poor study design and high heterogeneity. Also for some key areas such as floods, droughts and other weather extremes, there are no adequate systematic reviews of potential public health interventions.

CONCLUSION

In conclusion, we found the evidence base to be mostly weak for environmental interventions that could have the most value in a warmer world. Nevertheless, such interventions should not be dismissed. Future research on public health interventions for climate change adaptation needs to be concerned about quality in study design and should address the gap for floods, droughts and other extreme weather events that pose a risk to health.

Active trachoma and associated risk factors among children in Baso Liben District of East Gojjam, Ethiopia

Background

Trachoma is the leading cause of preventable blindness worldwide. It is common in areas where the people are socio-economically deprived. The aim of this study was to assess active trachoma and associated risk factors among children 1–9 years in East Gojjam.

Methods

Community-based cross-sectional study was conducted in Baso Liben District from February to April 2012. A two-stage random cluster-sampling technique was employed and all children 1–9 years old from each household were clinically assessed for trachoma based on simplified WHO 1983 classification. Data were collected by using semi-structured interview, pre-tested questionnaire and observation. The data were entered and analyzed using SPSS version 16 statistical package.

Results

From a total of 792 children screened for trachoma (of which 50.6% were girls), the overall prevalence of active trachoma was 24.1% consisting of only 17.2% [95% CI: 14.8, 20.1] TF and 6.8% TI. There were variations among children living in low land (29.3%) and in medium land (21.4%). In multivariate analysis, low monthly income (AOR = adjusted odds ratio) 2.98; 95% CI (confidence interval): 1.85-7.85), illiterate family (AOR = 5.18; 95% CI: 2.92-9.17); unclean face (AOR = 18.68; 95% CI: 1.98-175.55); access to water source (AOR = 2.01; 95% CI: 1.27-3.15); less than 20 liters of water use (AOR = 4.88; 95% CI: 1.51-15.78); not using soap for face washing (AOR = 5.84; 95% CI: 1.98-17.19); not using latrine frequently (AOR = 1.75; 95% CI: 0.01-0.42); density of flies (AOR = 3.77; 95% CI: 2.26-6.29); less knowledgeable family (AOR = 3.91; 95% CI: 2.40-6.38) and average monthly income (AOR = 2.98; 95% CI: 1.85-7.85) were found independently associated with trachoma.

Conclusion

Active trachoma is a major public problem among 1–9 years children and significantly associated with a number of risky factors. Improvement in awareness of facial hygiene, environmental conditions, mass antibiotic distribution and health education on trachoma transmission and prevention should be strengthened in the District.

Association between water related factors and active trachoma in Hai district, Northern Tanzania

BACKGROUND

Trachoma is widely distributed in sub-Saharan Africa and is mainly associated with poor water accessibility. However, these associations have never been demonstrated in some of the communities, especially in northern Tanzania. To cover that gap, the present case control study was conducted to assess the association of water related factors, general hygiene and active trachoma among preschool and school age children in Hai district, northern Tanzania.

RESULTS

Families reported to use > 60 litres of water per day were less likely to have active disease (OR= 0.4, 95% CI: 0.1 - 0.3; P<0.001) compared to households collecting ≤ 60 litres. The risk of having trachoma increased with increase in distance to the water point (OR= 6.5, 95% CI; 1.8 - 16.7; P= 0.003). Households members who reported to use < 2 liters of water for face washing were more likely to be trachomatous (OR= 5.12, 95% CI: 1.87-14.6, P = 0.001). Increased number of preschool children in the household was also associated with increased risk of active trachoma by 2.46 folds.

CONCLUSIONS

Improving water supply near the households and providing public health education focusing on improving households socio-economic status and individual hygiene especially in pre-school children in part will help to reduce the prevalence of the disease. In addition, integrating public health education with other interventions such as medical interventions remains important.

Risk factors for ocular chlamydia after three mass azithromycin distributions

Background

An important component of the World Health Organization's comprehensive trachoma elimination strategy is the provision of repeated annual mass azithromycin distributions, which are directed at reducing the burden of ocular chlamydia. Knowledge of characteristics associated with infection after mass antibiotic treatments could allow trachoma programs to focus resources to those most likely to be infected with ocular chlamydia.

Methodology/Principal Findings

We monitored 12 communities in rural Ethiopia that had received 3 annual mass azithromycin treatments as part of a cluster-randomized trial for trachoma. One year after the third treatment, a random sample of children from each village received conjunctival examination for follicular trachomatous inflammation (TF) and intense trachomatous inflammation (TI), conjunctival swabbing for chlamydial RNA and DNA, and a household survey. The primary outcome for this study was RNA evidence of ocular chlamydia, which we detected in 41 of 573 swabbed children (7.2%, 95%CI 2.7–17.8). In multivariate mixed effects logistic regression models, ocular chlamydial RNA was significantly associated with ocular discharge (OR 2.82, 95%CI 1.07–7.42), missing the most recent mass azithromycin treatment (OR 2.49, 95%CI 1.02–6.05), having a sibling with ocular chlamydia (OR 4.44, 95%CI 1.60–12.29), and above-median community population (OR 7.81, 95%CI 1.56–39.09). Ocular chlamydial infection was also independently associated with TF (OR 3.42, 95%CI 1.56–7.49) and TI (OR 5.39, 95%CI 2.43–11.98).

Conclusions/Significance

In areas with highly prevalent trachoma treated with multiple rounds of mass azithromycin, trachoma programs could consider continuing mass azithromycin treatments in households that have missed prior mass antibiotic treatments, in households with clinically active trachoma, and in larger communities.

Trachoma, which is the leading infectious cause of blindness worldwide, is caused by repeated ocular infection with Chlamydia trachomatis. Treatment for trachoma includes mass azithromycin treatments to the entire community. The World Health Organization recommends at least 3 rounds of annual mass antibiotic distributions in areas with trachoma, with further mass treatments based on the prevalence of trachoma. However, there are other options for communities that have received several rounds of treatment. For example, programs could continue antibiotic treatments only in those households most likely to have infected individuals. In this study, we performed trachoma monitoring on children from 12 Ethiopian communities one year after a third mass azithromycin treatment, and conducted a household survey at the same time. We found that children were more likely to be infected with ocular chlamydia if they had ocular inflammatory signs or ocular discharge, or if they had missed the preceding antibiotic treatment, had an infected sibling, or came from a larger community. These risk factors suggest that after mass azithromycin treatments, trachoma programs could consider continuing antibiotic distributions to households that have missed prior antibiotic distributions, in households with children who have the clinical signs of trachoma, and in larger communities.

The epidemiology of trachoma in the five northern districts of Sierra Leone

PURPOSE

In 2008, a trachoma prevalence survey was conducted in the five northern districts of Sierra Leone to determine if and where specific components of the SAFE strategy (Surgery, Antibiotics, Face washing, Environmental change) should be initiated.

METHODS

A cross-sectional survey at district level was implemented using two-stage random cluster sampling: probability proportionate sampling was used to select villages in the first stage and compact segment sampling of households in the second stage. Both eyes of 16,780 individuals were examined using the World Health Organization simplified trachoma grading system. Data were also collected on village- and household-level behavior and environmental factors related to trachoma.

RESULTS

Prevalence of trachomatous inflammation-follicular (TF) in children aged 1-9 years was highest in Kambia at 3.52% (95% Confidence Interval (CI): 2.28-4.75%), while the prevalence of trachomatous trichiasis (TT) in persons over 15 years of age was highest in Port Loko at 0.27% (95% CI: 0.03-0.50%). Across all districts, the percentage of households reporting washing children's faces less than once per day was very low, while latrine coverage and accessible and safe water sources were not highly prevalent.

CONCLUSIONS

In all districts but Koinadugu, TT prevalence was greater than the WHO elimination threshold, indicating the need for 1,016 TT surgeries to prevent blindness. District TF prevalence rates did not warrant mass antibiotic distribution. Although not required given the low prevalence of TF, we recommend the construction of 35,941 household latrines and provision of water sources within a 30-minute walk roundtrip for 17,551 households to bring Sierra Leone closer to reaching Millennium Development Goal 7.

Integrated monitoring and evaluation and environmental risk factors for urogenital schistosomiasis and active trachoma in Burkina Faso before preventative chemotherapy using sentinel sites

Background

Over 1 billion of the world's poorest inhabitants are afflicted by neglected tropical diseases (NTDs). Integrated control programmes aimed at tackling these debilitating NTDs have been recently initiated, mainly using preventative chemotherapy. Monitoring and evaluation (M&E) of these integrated programs presents particular challenges over and above those required for single disease vertical programmes. We used baseline data from the National NTD Control Programme in Burkina Faso in order to assess the feasibility of an integrated survey design, as well as to elucidate the contribution of environmental variables to the risk of either Schistosoma haematobium, trachoma, or both among school-aged children.

Methods

S. haematobium infection was diagnosed by detecting eggs in urine. A trachoma case was defined by the presence of Trachomatous inflammation-Follicular (TF) and/or Trachomatous inflammation-Intense (TI) in either eye. Baseline data collected from 3,324 children aged 7-11 years in 21 sentinel sites across 11 regions of Burkina Faso were analyzed using simple and multivariable hierarchical binomial logistic regression models fitted by Markov Chain Monte Carlo estimation methods. Probabilities of the risk of belonging to each infection/disease category were estimated as a function of age, gender (individual level), and environmental variables (at sentinel site level, interpolated from national meteorological stations).

Results

Overall prevalence at the sentinel sites was 11.79% (95% CI: 10.70-12.89) for S. haematobium; 13.30% (12.14-14.45) for trachoma and 0.84% (0.53-1.15) for co-infections. The only significant predictor of S. haematobium infection was altitude. There were significant negative associations between the prevalence of active trachoma signs and minimum temperature, and air pressure. Conditional upon these predictors, these data are consistent with the two pathogens being independent.

Conclusions

Urogenital schistosomiasis and trachoma constitute public health problems in Burkina Faso. Sentinel site (at school level) surveys for these two NTDs can be implemented simultaneously. However, to support MDA treatment decisions in Burkina Faso, the protocol used in this study would only be applicable to hypoendemic trachoma areas. More research is needed to confirm if these findings can be generalized to West Africa and beyond.

Trachoma prevalence and associated risk factors in the gambia and Tanzania: baseline results of a cluster randomised controlled trial

Background

Blinding trachoma, caused by ocular infection with Chlamydia trachomatis, is targeted for global elimination by 2020. Knowledge of risk factors can help target control interventions.

Methodology/Principal Findings

As part of a cluster randomised controlled trial, we assessed the baseline prevalence of, and risk factors for, active trachoma and ocular C. trachomatis infection in randomly selected children aged 0–5 years from 48 Gambian and 36 Tanzanian communities. Both children's eyes were examined according to the World Health Organization (WHO) simplified grading system, and an ocular swab was taken from each child's right eye and processed by Amplicor polymerase chain reaction to test for the presence of C. trachomatis DNA. Prevalence of active trachoma was 6.7% (335/5033) in The Gambia and 32.3% (1008/3122) in Tanzania. The countries' corresponding Amplicor positive prevalences were 0.8% and 21.9%. After adjustment, risk factors for follicular trachoma (TF) in both countries were ocular or nasal discharge, a low level of household head education, and being aged ≥1 year. Additional risk factors in Tanzania were flies on the child's face, being Amplicor positive, and crowding (the number of children per household). The risk factors for being Amplicor positive in Tanzania were similar to those for TF, with the exclusion of flies and crowding. In The Gambia, only ocular discharge was associated with being Amplicor positive.

Conclusions/Significance

These results indicate that although the prevalence of active trachoma and Amplicor positives were very different between the two countries, the risk factors for active trachoma were similar but those for being Amplicor positive were different. The lack of an association between being Amplicor positive and TF in The Gambia highlights the poor correlation between the presence of trachoma clinical signs and evidence of C. trachomatis infection in this setting. Only ocular discharge was associated with evidence of C. trachomatis DNA in The Gambia, suggesting that at this low endemicity, this may be the most important risk factor.

Trial Registration

ClinicalTrials.gov NCT00792922

Trachoma is caused by Chlamydia trachomatis and is the leading infectious cause of blindness. The World Health Organization's (WHO) control strategy includes antibiotic treatment of all community members, facial cleanliness, and environmental improvements. By determining how prevalent trachoma is, decisions can be made whether control activities need to be put in place. Knowing what factors make people more at risk of having trachoma can help target trachoma control efforts to those most at risk. We looked at the prevalence of active trachoma and C. trachomatis infection in the eyes of children aged 0–5 years in The Gambia and Tanzania. We also measured risk factors associated with having active trachoma or infection. The prevalence of both active trachoma and infection was lower in The Gambia (6.7% and 0.8%, respectively) than in Tanzania (32.3% and 21.9%, respectively). Risk factors for active trachoma were similar in the two countries. For infection, the risk factors in Tanzania were similar to those for TF, whereas in The Gambia, only ocular discharge was associated with infection. These results show that although the prevalence of active trachoma and infection is very different between the two countries, the risk factors for active trachoma are similar but those for infection are different.

Targeting trachoma control through risk mapping: the example of Southern Sudan

BACKGROUND

Trachoma is a major cause of blindness in Southern Sudan. Its distribution has only been partially established and many communities in need of intervention have therefore not been identified or targeted. The present study aimed to develop a tool to improve targeting of survey and control activities.

METHODS/PRINCIPAL FINDINGS

A national trachoma risk map was developed using Bayesian geostatistics models, incorporating trachoma prevalence data from 112 geo-referenced communities surveyed between 2001 and 2009. Logistic regression models were developed using active trachoma (trachomatous inflammation follicular and/or trachomatous inflammation intense) in 6345 children aged 1-9 years as the outcome, and incorporating fixed effects for age, long-term average rainfall (interpolated from weather station data) and land cover (i.e. vegetation type, derived from satellite remote sensing), as well as geostatistical random effects describing spatial clustering of trachoma. The model predicted the west of the country to be at no or low trachoma risk. Trachoma clusters in the central, northern and eastern areas had a radius of 8 km after accounting for the fixed effects.

CONCLUSION

In Southern Sudan, large-scale spatial variation in the risk of active trachoma infection is associated with aridity. Spatial prediction has identified likely high-risk areas to be prioritized for more data collection, potentially to be followed by intervention.

Prevalence and risk factors for trachoma in central and southern Malawi

Background

Trachoma, one of the neglected tropical diseases is suspected to be endemic in Malawi. Objectives: To determine the prevalence of trachoma and associated risk factors in central and southern Malawi.

Methodology/Principal Findings

A population based survey conducted in randomly selected clusters in Chikwawa district (population 438,895), southern Malawi and Mchinji district (population 456,558), central Malawi. Children aged 1–9 years and adults aged 15 and above were assessed for clinical signs of trachoma. In total, 1010 households in Chikwawa and 1016 households in Mchinji districts were enumerated within 108 clusters (54 clusters in each district). A total of 6,792 persons were examined for ocular signs of trachoma. The prevalence of trachomatous inflammation, follicular (TF) among children aged 1–9 years was 13.6% (CI 11.6–15.6) in Chikwawa and 21.7% (CI 19.5–23.9) in Mchinji districts respectively. The prevalence of trachoma trichiasis (TT) in women and men aged 15 years and above was 0.6% (CI 0.2–0.9) in Chikwawa and 0.3% (CI 0.04–0.6) in Mchinji respectively. The presence of a dirty face was significantly associated with trachoma follicular (TF) in both Chikwawa and Mchinji districts (P<0.001).

Conclusion/Significance

Prevalence rates of trachoma follicles (TF) in Central and Southern Malawi exceeds the WHO guidelines for the intervention with mass antibiotic distribution (TF>10%), and warrants the trachoma SAFE control strategy to be undertaken in Chikwawa and Mchinji districts.

Access to water source, latrine facilities and other risk factors of active trachoma in Ankober, Ethiopia

Objective

This study aims to determine the prevalence and correlates of active trachoma in Ankober, Ethiopia.

Methods

A cross-sectional community-based study was conducted during July 2007. A total of 507 children (ages 1–9 years), from 232 households were included in the study. All children were examined for trachoma by ophthalmic nurses using the WHO simplified clinical grading system. Interviews and observations were used to assess risk factors. Logistic regression procedures were used to determine associations between potential risk factors and signs of active trachoma.

Results

Overall, the prevalence of active trachoma was found to be 53.9% (95%CI 49.6%–58.2%). Presence of fly-eye (fly contact with the eyelid margin during eye examination) (Odds Ratio (OR) = 4.03 95% CI 1.40–11.59), absence of facial cleanliness (OR = 7.59; 95%CI 4.60–12.52), an illiterate mother (OR = 5.88; 95%CI 2.10–15.95), lack of access to piped water (OR = 2.19; 95%CI 1.14–6.08), and lack of access to latrine facilities (OR = 4.36; 95%CI 1.49–12.74) were statistically significantly associated with increased risk of active trachoma.

Conclusion

Active trachoma among children 1–9 years of age in Ankober is highly prevalent and significantly associated with a number of risk factors including access to water and latrine facilities. Trachoma prevention programs that include improved access to water and sanitation, active fly control, and hygiene education are recommended to lower the burden of trachoma in Ankober, Ethiopia.

Risk factors for active trachoma in The Gambia

Trachoma has been endemic in The Gambia for decades but national surveys indicate that the prevalence is falling. Risk factor data can help guide trachoma control efforts. This study investigated risk factors for active trachoma and ocular Chlamydia trachomatis infection in children aged below 10 years in two Gambian regions. The overall prevalence of C. trachomatis infection was only 0.3% (3/950) compared with 10.4% (311/2990) for active trachoma, therefore analyses were only performed for active trachoma. After adjustment, increased risk of trachoma was associated with being aged 1-2 years (odds ratio (OR) 2.20, 95% CI 1.07-4.52) and 3-5 years (OR 3.62, 95% CI 1.80-7.25) compared with <1 year, nasal discharge (OR 2.07, 95% CI 1.53-2.81), ocular discharge (OR 2.68, 95% CI 1.76-4.09) and there being at least one other child in the household with active trachoma (OR 11.28, 95% CI 8.31-15.31). Compared with other occupations, children of traders had reduced risk (OR 0.53, 95% CI 0.30-0.94). At the household level, only the presence of another child in the household with active trachoma was associated with increased risk of active trachoma, suggesting that current trachoma control interventions are effective at this level. In contrast, child-level factors were associated with increased risk after adjustment, indicating a need to increase control efforts at the child level.

The burden of trachoma in Ayod County of Southern Sudan

Background

Blindness due to trachoma is avoidable through Surgery, Antibiotics, Facial hygiene and Environmental improvements (SAFE). Recent surveys have shown trachoma to be a serious cause of blindness in Southern Sudan. We conducted this survey in Ayod County of Jonglei State to estimate the need for intervention activities to eliminate blinding trachoma.

Methodology and Findings

A cross-sectional two-stage cluster random survey was conducted in November 2006. All residents of selected households were clinically assessed for trachoma using the World Health Organization (WHO) simplified grading scheme. A total of 2,335 people from 392 households were examined, of whom 1,107 were over 14 years of age. Prevalence of signs of active trachoma in children 1–9 years of age was: trachomatous inflammation follicular (TF) = 80.1% (95% confidence interval [CI], 73.9–86.3); trachomatous inflammation intense (TI) = 60.7% (95% CI, 54.6–66.8); and TF and/or TI (active trachoma) = 88.3% (95% CI, 83.7–92.9). Prevalence of trachomatous trichiasis (TT) was 14.6% (95% CI, 10.9–18.3) in adults over 14 years of age; 2.9% (95% CI, 0.4–5.3) in children 1–14 years of age; and 8.4% (95% CI, 5.5–11.3) overall. The prevalence of corneal opacity in persons over 14 years of age with TT was 6.4% (95% CI, 4.5–8.3). No statistically significant difference was observed in the prevalence of trachoma signs between genders. Trachoma affected almost all households surveyed: 384/392 (98.0%) had at least one person with active trachoma and 130 (33.2%) had at least one person with trichiasis.

Conclusions

Trachoma is an unnecessary public health problem in Ayod. The high prevalence of active trachoma and trichiasis confirms the severe burden of blinding trachoma found in other post-conflict areas of Southern Sudan. Based on WHO recommended thresholds, all aspects of the SAFE strategy are indicated to eliminate blinding trachoma in Ayod.

Trachoma, a neglected tropical disease, is the leading cause of infectious blindness and is targeted for global elimination by the year 2020. We conducted a survey in Ayod County of Jonglei State, Southern Sudan, to determine whether blinding trachoma was a public health problem and to plan interventions to control this disease. We found the burden of trachoma in Ayod to be one of the most severe ever documented. Not only were adults affected by the advanced manifestations of the disease as is typical for older age groups, but young children were also affected. At least one person with clinical signs of trachoma was found in nearly every household, and 1 in 3 households had a person with severe blinding trachoma. Characteristics previously identified as risk factors were ubiquitous among surveyed households, but we were unable to identify why trachoma is so severe in this location. Surgical interventions are needed urgently to improve vision and prevent irreversible blindness in children and adults. Mass antibiotic distribution may alleviate current infections and transmission of trachoma may be reduced if communities adopt the behavior of face washing and safe disposal of human waste. Increasing access to improved water sources may not only improve hygiene but also reduce the spread of guinea worm and other water-borne diseases.

Risk factors for active trachoma and Chlamydia trachomatis infection in rural Ethiopia after mass treatment with azithromycin

OBJECTIVES

To investigate risk factors for ocular Chlamydia trachomatis infection and active trachoma, comparing communities receiving or not receiving an intervention programme of community-wide azithromycin treatment and health education.

METHODS

In a 3-year post-intervention follow-up survey, 1722 children aged 3-9 years, from randomly selected households in 37 communities, were examined for signs of active trachoma and had samples taken to test for ocular C. trachomatis by polymerase chain reaction. Multivariate random effects logistic regression analyses considered interventions at community level, adjusting for other independent risk factors as appropriate.

RESULTS

Younger age, ocular discharge and flies on eyes were risk factors for active trachoma in communities with and without antibiotic treatment. After azithromycin treatment, odds of active trachoma were lower in children aged 6-9 years than in children aged 3-5 years (OR 0.48, 95% CI: 0.36-0.66) and higher for children with ocular discharge (OR 4.5, 95% CI: 2.6-7.7) or flies on their eyes (OR 2.5, 95% CI: 1.6-3.7). Odds of C. trachomatis infection were lower in children aged 6-9 years than in younger children (OR 0.47, 95% CI: 0.23-0.96); and in children who received 2 or 3 doses rather than 1 (OR 0.26, 95% CI: 0.08-0.88).

CONCLUSIONS

In communities that received or did not receive the mass antibiotic treatment, the same risk factors for C. trachomatis and active trachoma were identified. Education and environmental improvements need to supplement antibiotic campaigns in order to positively impact on these remaining child level risk factors.