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Assessing the feasibility of 2030 as a target date for global elimination of trachoma, and identification of districts that may require enhanced treatment to meet World Health Organization (WHO) elimination criteria by this date are key challenges in operational planning for trachoma programmes. Here we address these challenges by prospectively evaluating forecasting models of trachomatous inflammation-follicular (TF) prevalence, leveraging ensemble-based approaches. Seven candidate probabilistic models were developed to forecast district-wise TF prevalence in 11 760 districts, trained using district-level data on the population prevalence of TF in children aged 1-9 years from 2004 to 2022. Geographical location, history of mass drug administration treatment, and previously measured prevalence data were included in these models as key predictors. The best-performing models were included in an ensemble, using weights derived from their relative likelihood scores. To incorporate the inherent stochasticity of disease transmission and challenges of population-level surveillance, we forecasted probability distributions for the TF prevalence in each geographic district, rather than predicting a single value. Based on our probabilistic forecasts, 1.46% (95% confidence interval [CI]: 1.43-1.48%) of all districts in trachoma-endemic countries, equivalent to 172 districts, will exceed the 5% TF control threshold in 2030 with the current interventions. Global elimination of trachoma as a public health problem by 2030 may require enhanced intervention and/or surveillance of high-risk districts.

Trachoma is targeted for elimination as a public health problem worldwide by 2030. In Nigeria, elimination activities are implemented at the local government area (LGA) level. They started in 2002 by conducting baseline population-based prevalence surveys (PBPSs), which continued in a systematic manner with engagement from the Global Trachoma Mapping Project in 2013, and subsequently Tropical Data. The results led to the development of Nigeria's first trachoma action plan and its subsequent revision with additional information. Following 449 baseline PBPSs, 122 LGAs had an active trachoma prevalence above the elimination threshold, requiring interventions, while 231 LGAs required community-based interventions for trichiasis management. By 2021, >34 million antibiotic treatments had been provided in 104 LGAs, with 89 LGAs eliminating active trachoma. Nationally, water and sanitation coverages increased by 3% and 18%, respectively, in 7 y. Systematic trichiasis case finding and management were carried out in 231 LGAs, resulting in the management of 102 527 people. Fifty-four LGAs decreased trichiasis prevalence unknown to the health system to <0.2% in persons ≥15 y of age. Where this elimination prevalence threshold was reached, trichiasis services were transitioned to routine eye/healthcare systems. Such progress relied on strong leadership and coordination from the national trachoma program and tremendous support provided by partners. Attaining elimination of trachoma as a public health problem in Nigeria by 2030 is feasible if funding support is sustained. [ABSTRACT FROM AUTHOR]

PurposeTo determine the prevalence of trachoma in four Local Government Areas (LGAs) of Kogi State, Nigeria.MethodsIn June 2014, we conducted population-based, cross-sectional surveys according to Global Trachoma Mapping Project (GTMP) protocols in selected LGAs of Kogi State. In each LGA, 25 clusters were selected with probability proportional to size. In each of these clusters, 25 households were enrolled for the survey. All residents of selected households aged ≥1 year were examined by GTMP-certified graders for trachomatous inflammation-follicular (TF) and trichiasis using the simplified trachoma grading scheme. Data on sources of household water and types of sanitation facilities were collected through questioning and direct observation.ResultsThe age-adjusted TF prevalence in 1-9-year-olds ranged from 0.4% (95% CI 0.1-0.8%) in Bassa to 1.0% (95% CI 0.3-1.9%) in Omala. Across all four LGAs, only one case of trichiasis was found; this individual was in Omala, giving that LGA a trichiasis prevalence in individuals aged ≥15 years of 0.02% (95% CI 0.00-0.07%). Between 77 and 88% of households had access to water for hygiene purposes, while only 10-30% had access to improved sanitation facilities.ConclusionTrachoma is not a public health problem in any of the 4 LGAs surveyed. There is, however, the need to increase access to adequate water and sanitation services to contribute to the health and social and economic well-being of these communities.

PurposeThe World Health Organization's (WHO's) global trachoma elimination programme recommends mapping of trachoma at district level for planning of elimination activities in affected populations. This study aimed to provide data on trachoma prevalence for the Area Councils of Nigeria's Federal Capital Territory (FCT).MethodsUsing the Global Trachoma Mapping Project (GTMP) protocols, in March and April 2014, we conducted a population-based cross-sectional survey in each of the six Area Councils of FCT. Signs were defined based on the WHO simplified grading scheme.Results98% to 100% of the targeted households were enrolled in each Area Council. The number of children aged 1-9 years examined per Area Council ranged from 867 to 1248. The number of persons aged ≥15 years examined ranged from 1302 to 1836. The age-adjusted prevalence of trachomatous inflammation-follicular in 1-9-year-olds was

PurposeThe purpose of these surveys was to determine the prevalence of trachomatous inflammation-follicular (TF) in children aged 1-9 years and trichiasis prevalence in persons aged ≥15 years, in 13 Local Government Areas (LGAs) of Taraba State, Nigeria.MethodsThe surveys followed Global Trachoma Mapping Project (GTMP) protocols. Twenty-five households were selected from each of 25 clusters in each LGA, using two-stage cluster sampling providing probability of selection proportional to cluster size. Survey teams examined all the residents of selected households aged ≥1 year for the clinical signs TF, trachomatous inflammation-intense (TI) and trichiasis.ResultsThe prevalence of TF in children aged 1-9 years in the 13 LGAs ranged from 0.0-5.0%; Ussa LGA had the highest prevalence of 5% (95%CI: 3.4-7.2). Trichiasis prevalence ranged from 0.0-0.8%; seven LGAs had trichiasis prevalences above the threshold for elimination. The backlog of trichiasis in the 13 LGAs (estimated combined population 1,959,375) was 3,185 people. There is need to perform surgery for at least 1,835 people to attain a trichiasis prevalence in each LGA of 80% of households with access to improved latrines.ConclusionOne of 13 LGAs requires antibiotic mass drug administration for active trachoma. Community-based trichiasis surgery needs to be provided in seven LGAs. There is a need to increase household-level access to improved washing water and latrines across the State.

PurposeTo determine prevalence of trachoma after interventions in 15 local government areas (LGAs) of Kebbi, Sokoto and Zamfara States, Nigeria.MethodsA population-based impact survey was conducted in each LGA using Global Trachoma Mapping Project (GTMP) protocols. In each LGA, 25 villages were selected, except in Arewa LGA, where we selected 25 villages from each of four subunits to obtain finer-resolution prevalence information. Villages were selected with probability proportional to size. In each village, 25 households were enrolled and all consenting residents aged ≥1 year were examined by GTMP-certified graders for trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT). Information on sources of household water and types of sanitation facilities used was collected through questioning and direct observation.ResultsThe number of households enrolled per LGA ranged from 623 (Kware and Tangaza) to 2488 (Arewa). There have been marked reductions in the prevalence of TF and TT since baseline surveys were conducted in all 15 LGAs. Eight of the 15 LGAs have attained TF prevalences

PurposeTo determine the prevalence of and risk factors for trachoma in selected local government areas (LGAs) of Kwara State, Nigeria.MethodologyPopulation-based cross-sectional surveys were conducted in eight LGAs of Kwara State using Global Trachoma Mapping Project (GTMP) protocols. In each LGA, 25 villages were selected using probability-proportional-to-size sampling; 25 households were selected from each village using compact segment sampling. All residents of selected households aged ≥1 year were examined by GTMP-certified graders for trachomatous inflammation-follicular (TF) and trichiasis using the simplified trachoma grading scheme. Water, sanitation, and hygiene (WASH) data were also collected.ResultsA total of 28,506 residents were enumerated in 4769 households across the eight LGAs. TF prevalence in children aged 1-9 years ranged from 0.2% (95% CI 0.0-0.3%) to 1.3% (95% CI 0.7-2.1%), while trichiasis prevalence in persons ≥15 years was

PurposeWe sought to determine the prevalence of trachoma in each local government area (LGA) of Benue State, Nigeria.MethodsTwo-stage cluster sampling was used to conduct a series of 23 population-based prevalence surveys. LGAs were the evaluation units surveyed. In each LGA, 25 households were selected in each of 25 clusters, and individuals aged 1 year and above resident in those households were invited to be examined for trachoma. Data on access to water and sanitation were also collected at household level.ResultsA total of 91,888 people were examined from among 93,636 registered residents across the 23 LGAs. The LGA-level prevalence of trachomatous inflammation-follicular (TF) in 1-9 year olds ranged from 0.3% to 5.3%. Two LGAs had TF prevalences of 5.0-9.9%. The LGA-level prevalence of trichiasis in ≥15-year-olds ranged from 0.0% to 0.35%. Access to improved drinking water sources ranged from 0% in Gwer West to 99% in Tarka, while access to improved sanitation ranged from 1% in Gwer West to 92% in Oturkpo.ConclusionThere is a need for public health-level interventions against trachoma in three LGAs of Benue State.

PurposeTo determine the prevalence of trachoma and water and sanitation coverage in four local government areas (LGAs) of Jigawa State, Nigeria: Birnin Kudu, Buji, Dutse and Kiyawa.MethodologyA population-based cross-sectional survey was conducted in each LGA using Global Trachoma Mapping Project (GTMP) protocols. From each LGA, 25 villages were selected using probability-proportional-to-population size sampling; in each village, 25 households were selected using the random walk technique. All residents aged ≥1 year in selected households were examined by GTMP-certified graders for trachomatous inflammation - follicular (TF) and trichiasis, defined according to the WHO simplified trachoma grading scheme definitions. Water, sanitation and hygiene data were also collected through questioning and direct observation.ResultsIn 2458 households of four LGAs, 10,669 residents were enumerated. A total of 9779 people (92% of residents) were examined, with slightly more females examined (5012; 51%) than men. In children aged 1-9 years, the age-adjusted prevalence of TF ranged from 5.1% (95% CI 2.5-9.0%) in Birnin Kudu to 12.8% (95% CI 7.6-19.4%) in Kiyawa, while the age- and gender-adjusted trichiasis prevalence in persons aged ≥15 years ranged from 1.9% (95% CI 1.4-2.5%) in Birnin Kudu to 3.1% (95% CI 2.2-4.0) in Dutse. Access to improved water sources was above 80% in all LGAs surveyed but access to improved sanitation facilities was low, ranging from 23% in Buji to 50% in Kiyawa.ConclusionTrachoma is a public health problem in all four LGAs surveyed. The full SAFE strategy needs to be implemented to achieve trachoma elimination.

Background The WHO recommends mass drug administration (MDA) as a strategy to deliver safe and cost-effective medicines to prevent and treat diseases. The antibiotic, azithromycin, has been used during MDA for the treatment and prevention of trachoma in Nigeria. Azithromycin has recently been shown to reduce infant mortality in communities receiving it for trachoma-elimination purposes in sub-Saharan Africa. This article reports on the implementation strategies for the safety and antimicrobial resistance of mass administration of azithromycin to children aged 1–11 mo using the trachoma programme platform in Kebbi state. Methods The mass administration of azithromycin among 1–11-mo-olds in Kebbi was implemented in three phases: (i) the preimplementation phase, during which specific activities were conducted to achieve government and community buy-in, ownership and capacity building; (ii) the implementation phase, which included the mass administration of azithromycin carried out by community volunteers (also known as community-directed distributors [CDDs]), monitoring (by health workers and independent monitors) and reporting of the distribution by all personnel; and (iii) the postimplementation phase, which included the validation of community data, where each item of community summary data is verified and checked for completeness and accuracy before uploading to the District Health Information System platform, where data are visualised, analysed and stored. Results In total, 97% of the target population received treatment; the remaining 3% were not treated due to signs of ill health, history of allergy to antibiotics, parental refusal or absence at the time of MDA. Children aged 1–11 mo accounted for 17% of the under-5 population, with females constituting 56% of the target population. In communities that were monitored, reports showed that only 5% lacked distribution materials (scales, slings or registers), >80% correctly entered data into community registers and 5% of children were not treated due to inadequate azithromycin provided to the CDDs for distribution. Conclusion The implementation of azithromycin MDA for children aged 1–11 mo in Kebbi, utilising the trachoma platform, exhibited commendable coverage due to existing programme platform, healthcare and community structures, intensive advocacy and social mobilisation, real-time monitoring and progress-tracking strategies. It also demonstrated that the trachoma platform is suitable for implementing public health interventions, even after the elimination of trachoma in previously endemic districts. [ABSTRACT FROM AUTHOR]

Trachoma is a disease of the eye and the leading infectious cause of blindness worldwide. Years of repeated infections can cause in-turning of the lashes so that they rub against the eyeball, causing pain, discomfort and, if left untreated, blindness. This is known as trachomatous trichiasis (TT) and can be remedied by surgery. To improve oversight and reporting of TT outreach, Sightsavers developed a mobile phone application called the TT Tracker so that TT surgeons, assistants and supervisors can collect and analyse information about surgical outcomes and performance and determine when and where follow-up appointments are required. The TT Tracker is being used by seven national programmes. Examples of use and programme improvements from Nigeria, Benin and Senegal are discussed here. [ABSTRACT FROM AUTHOR]

Background Achieving elimination of trachoma as a public health problem in trichiasis-endemic districts requires a systematic approach to trichiasis case finding and outreach. Methods Programme monitoring data from seven countries for 2017–2019 were used to explore the efficiency of different community mobilisation approaches and uptake of trichiasis surgical services. Results Three countries (Ethiopia, Kenya and Mozambique) using broad-based community mobilisation strategies had large numbers of people presenting at outreach but only 2.9% of them had trichiasis, while in four countries (Nigeria, Tanzania, Uganda and Zambia) using house-to-house case finding, 37.5% of outreach attendees had trichiasis. Countries using house-to-house case finding have proportionally more women attending outreach compared with countries using broad-based mobilisation. Among trichiasis cases offered surgery 86% accepted, which was similar for men and women. Conclusions In these settings, house-to-house case finding appears to be a more effective and efficient approach to ensure that trichiasis cases, particularly in women, obtain access to surgical services. [ABSTRACT FROM AUTHOR]

Sample sizes in cluster surveys must be greater than those in surveys using simple random sampling in order to obtain similarly precise prevalence estimates, because results from subjects examined in the same cluster cannot be assumed to be independent. Therefore, a crucial aspect of cluster sampling is estimation of the intracluster correlation coefficient (ρ): the degree of relatedness of outcomes in a given cluster, defined as the proportion of total variance accounted for by between-cluster variation. In infectious disease epidemiology, this coefficient is related to transmission patterns and the natural history of infection; its value also depends on particulars of survey design. Estimation of ρ is often difficult due to the lack of comparable survey data with which to calculate summary estimates. Here we use a parametric bootstrap model to estimate ρ for the ocular clinical sign "trachomatous inflammation—follicular" (TF) among children aged 1–9 years within population-based trachoma prevalence surveys. We present results from a meta-regression analysis of data from 261 such surveys completed using standardized methods in Ethiopia, Mozambique, and Nigeria in 2012–2015. Consistent with the underlying theory, we found that ρ increased with increasing overall TF prevalence and smaller numbers of children examined per cluster. Estimates of ρ for TF were independently higher in Ethiopia than in the other countries. [ABSTRACT FROM AUTHOR]

Background: Trachomatous trichiasis (TT) is a painful, potentially blinding eye condition that can be managed through epilation or surgery. Women are affected by TT approximately twice as often as men and are believed to face gendered barriers to receiving surgical care to prevent vision loss., Methods: We used data from 817 cross-sectional surveys conducted during 2015-2019 in 20 African countries to estimate the prevalence difference (PD) between female and male eyes for four outcomes potentially indicating gender-related differences in TT management: (1) received surgery and developed postoperative TT (PTT), (2) never offered surgery, (3) offered surgery but declined it, and (4) offered epilation but never offered surgery., Results: The prevalence was modestly elevated among female eyes compared with male eyes for having PTT (PD:1.8 [95% confidence limits (CL): 0.6, 3.0]) and having declined surgery for the eye (PD: 6.2 [95% CL: 1.8, 10.7]). The proportion offered epilation was similar by gender (PD:0.5 [95% CL: -0.4, 1.3]), while never having been offered surgery was somewhat more prevalent among male eyes (PD: -2.1 [95% CL: -3.5, -0.7])., Conclusions: Our results suggest potential gender differences in TT management. More research is needed to determine the causes and implications of the observed differences., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

In collaboration with the health ministries that we serve and other partners, we set out to complete the multiple-country Global Trachoma Mapping Project. To maximize the accuracy and reliability of its outputs, we needed in-built, practical mechanisms for quality assurance and quality control. This article describes how those mechanisms were created and deployed. Using expert opinion, computer simulation, working groups, field trials, progressively accumulated in-project experience, and external evaluations, we developed 1) criteria for where and where not to undertake population-based prevalence surveys for trachoma; 2) three iterations of a standardized training and certification system for field teams; 3) a customized Android phone-based data collection app; 4) comprehensive support systems; and 5) a secure end-to-end pipeline for data upload, storage, cleaning by objective data managers, analysis, health ministry review and approval, and online display. We are now supporting peer-reviewed publication. Our experience shows that it is possible to quality control and quality assure prevalence surveys in such a way as to maximize comparability of prevalence estimates between countries and permit high-speed, high-fidelity data processing and storage, while protecting the interests of health ministries.