Facial cleanliness and sanitation are postulated to reduce trachoma transmission, but there are no previous data on community-level herd protection thresholds. We characterize associations between ...active trachoma, access to improved sanitation facilities, and access to improved water sources for the purpose of face washing, with the aim of estimating community-level or herd protection thresholds.
We used cluster-sampled Global Trachoma Mapping Project data on 884,850 children aged 1-9 years from 354,990 households in 13 countries. We employed multivariable mixed-effects modified Poisson regression models to assess the relationships between water and sanitation coverage and trachomatous inflammation-follicular (TF). We observed lower TF prevalence among those with household-level access to improved sanitation (prevalence ratio, PR = 0.87; 95%CI: 0.83-0.91), and household-level access to an improved washing water source in the residence/yard (PR = 0.81; 95%CI: 0.75-0.88). Controlling for household-level water and latrine access, we found evidence of community-level protection against TF for children living in communities with high sanitation coverage (PR80-90% = 0.87; 95%CI: 0.73-1.02; PR90-100% = 0.76; 95%CI: 0.67-0.85). Community sanitation coverage levels greater than 80% were associated with herd protection against TF (PR = 0.77; 95%CI: 0.62-0.97)-that is, lower TF in individuals whose households lacked individual sanitation but who lived in communities with high sanitation coverage. For community-level water coverage, there was no apparent threshold, although we observed lower TF among several of the higher deciles of community-level water coverage.
Our study provides insights into the community water and sanitation coverage levels that might be required to best control trachoma. Our results suggest access to adequate water and sanitation can be important components in working towards the 2020 target of eliminating trachoma as a public health problem.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
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.
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.
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.
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.
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.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background/aimsThe COVID-19 pandemic necessitated the use of personal protective equipment for those involved in trachoma survey grading and trichiasis surgery. We sought to determine which ...configuration of a face shield would be less likely to impact grading accuracy and ability to conduct trichiasis surgery. The research also included assessment of comfort, ease of cleaning and robustness.MethodsThere were three research phases. In phase 1, assessment of four potential face shield configurations was undertaken with principal trachoma graders and trichiasis surgeon trainers to decide which two options should undergo further testing. In phase 2, clarity of vision and comfort (in a classroom environment) of the two configurations were assessed compared with no face shield (control), while grading trachomatous inflammation—follicular (TF). The second phase also included the assessment of impact of the configurations while performing trichiasis surgery using a training model. In phase 3, face shield ease of use was evaluated during routine surgical programmes.ResultsIn phase 2, 124 trachoma graders and 28 trichiasis surgeons evaluated the 2 face shield configurations selected in phase 1. TF agreement was high (kappa=0.83 and 0.82) for both configurations compared with not wearing a face shield. Comfort was reported as good by 51% and 32% of graders using the two configurations. Trichiasis skill scores were similar for both configurations.ConclusionThe face shield configuration that includes a cut-out for mounting the 2.5× magnifying loupes does not appear to impact the ability or comfort of trachoma graders or trichiasis surgeons to carry out their work.
Abstract
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
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
Background
The neglected tropical disease (NTD) sector is adapting to the uncertain circumstances of coronavirus disease 2019 (COVID-19). The development of the Risk Assessment and ...Mitigation Action (RAMA) tool was driven by partners of the programme Accelerating the Sustainable Control and Elimination of NTDs (hereafter called Ascend) to enable countries to recommence NTD activities following the World Health Organization advisories of April and July 2020. This article explores the advantages of the RAMA process for NTD delivery.
Methods
The analysis used interview transcripts with NTD practitioners in Cote d'Ivoire, Guinea, Liberia and Nigeria and results from the monitoring of compliance with COVID-19 mitigation measures in Nigeria.
Results
Three themes emerged from the results: adaptability and innovation, collaboration and government ownership and preparedness.
Conclusions
The advantages of the RAMA tool suggest its importance in mitigating the transmission of COVID-19 during NTD delivery. There is the potential for the tool to be adapted for use throughout future pandemics.
In 2019-2020, one round of antibiotic mass drug administration (MDA) was implemented for trachoma elimination purposes in Donga, Gashaka, and Ussa local government areas (LGAs) of Taraba State, ...Nigeria, following baseline surveys in 2009 (Donga and Gashaka) and 2013-2014 (Ussa). Here, trachoma prevalence post-MDA in these three LGAs is reported.
In 2019 (Gashaka and Ussa) and 2020 (Donga), population-based, cross-sectional surveys were conducted following World Health Organization (WHO) guidance. A two-stage cluster sampling strategy was used. All residents of selected households aged ≥1 year were examined by Tropical Data-certified graders for trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT) using the WHO simplified trachoma grading scheme. Data on water, sanitation, and hygiene (WASH) access were also collected.
A total of 1,883 households participated. From these households, 4,885 children aged 1-9 years were enumerated, and 4,866 (99.6%) examined. There were 5,050 eligible adults (aged ≥15 years) enumerated in the same households, of whom 4,888 (96.8%) were examined. Age-adjusted TF prevalence in children aged 1-9 years was 0.22% (95% CI: 0.00-0.65) in Donga, 0.0% in Gashaka, and 0.19% (95% CI: 0.00-0.44) in Ussa. The age- and gender-adjusted TT prevalence unknown to the health system in adults aged ≥15 years was 0.08% (95% CI: 0.00-0.19) in Donga, 0.02% (95% CI: 0.00-0.06) in Gashaka, and 0.10% (95% CI: 0.01-0.18) in Ussa. In Donga, Gashaka, and Ussa, respectively, 66%, 49% and 63% of households had access to an improved drinking water source, and 68%, 56% and 29% had access to an improved latrine.
In all LGAs, the elimination thresholds for TF and TT unknown to the health system have been attained in the target age groups. These LGAs should be re-surveyed after 2 years to show that reductions in TF prevalence have been sustained in the absence of MDA. Health authorities should continue to improve WASH facilities to reduce the risk of later recrudescence.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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.
To determine the prevalence of trachoma in each of the 21 local government areas (LGAs) of Adamawa State, Nigeria.
A population-based cross-sectional survey was conducted in each of the 21 LGAs of ...Adamawa State between 2017 and 2019. With the support of Tropical Data (TD), surveys were planned and implemented in accordance with World Health Organization (WHO) recommendations. A two-stage cluster sampling technique was used in each LGA, 25 or 30 clusters were selected with a probability of selection proportionate to cluster size, and in each of these clusters, 25 or 30 households were enrolled for the survey. All residents aged 1 year and older within selected households were examined by TD-certified graders for trachomatous inflammation - follicular (TF) and trachomatous trichiasis (TT) using the WHO simplified grading scheme. Additionally, data were collected on household water and sanitation access.
All 21 LGAs had TF prevalence in 1-9-year-olds below 5%. The prevalence of TT unknown to the health system in people aged ≥15 years was ≥0.2% in three of the 21 LGAs. Access to improved water and sanitation facilities was <80% in the majority of the surveyed LGAs. Only 12 of the 21 LGAs had ≥50% household-level improved latrine access, and only Yola North had ≥80% household-level improved latrine access.
There is no need for mass treatment with antibiotics for trachoma elimination purposes in any of these LGAs. There is a need for active TT case finding and provision of community-based TT surgical services in three LGAs. Furthermore, engagement with water and sanitation agencies is needed to augment access to improved water and sanitation facilities across the State; this will help to avoid the recrudescence of active trachoma in the State.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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