Ophthalmic epidemiology最新文献

Purpose: Trachoma is a public health problem in 42 countries. Inflammation associated with repeated ocular infection with Chlamydia trachomatis can cause the eyelid to scar and turn inwards, resulting in the eyelashes rubbing against the eyeball, known as trachomatous trichiasis (TT). In Guinea, baseline surveys conducted in 2013 reported inflammatory trachoma prevalences below the World Health Organization (WHO) threshold for elimination, but TT prevalences above threshold. Given this epidemiological context and time since baseline survey, TT-only surveys were conducted in selected districts to determine current TT prevalence. The results of this study provide critical data for assessing Guinea's achievement of trachoma elimination targets.

Methods: Four health districts, consisting of six evaluation units (EU), were surveyed. In each EU, field teams visited 29 clusters with a minimum 30 households included in each. Participants aged≥15 years were examined by certified graders trained to identify TT and determine whether management had been offered.

Results: A total of 22,476 people were examined, with 48 TT cases across the six EUs identified. Five of six EUs had an age-and-gender adjusted TT-prevalence unknown to the health system less than 0.2%, whereas one EU, Beyla 2, had an adjusted TT prevalence of 0.24%.

Conclusion: These TT-only surveys, along with findings from other trachoma interventions, suggest that Guinea is close to achieving elimination of trachoma as a public health problem. This study demonstrates the value of undertaking TT-only surveys in settings where baseline surveys indicated active trachoma prevalences below WHO elimination threshold, but TT prevalences above it.

Purpose: The prevalence of trachomatous inflammation-follicular (TF) in Papua New Guinea (PNG) suggests antibiotic mass drug administration (MDA) is needed to eliminate trachoma as a public health problem but the burden of trichiasis is low. As a result, WHO issued bespoke recommendations for the region. If ≥ 20% of 10-14-year-olds have both any conjunctival scarring (C1 or C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. Equally, if ≥ 5% of that group have both moderate/severe conjunctival scarring (C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued.

Methods: We identified 14 villages where > 20% of 1-9-year-olds had TF during baseline mapping undertaken 4 years and 1 month previously. Every child aged 10-14 years in those villages was eligible to be examined for clinical signs of corneal pannus, Herbert's pits and conjunctival scarring. A grading system that built on existing WHO grading systems was used.

Results: Of 1,293 resident children, 1,181 (91%) were examined. Of 1,178 with complete examination data, only one (0.08%) individual had concurrent scarring and limbal signs.

Conclusions: The WHO-predefined criteria for continuation of MDA were not met. Ongoing behavioural and environmental improvement aspects of the SAFE strategy may contribute to integrated NTD control. Surveillance methods should be strengthened to enable PNG health authorities to identify future changes in disease prevalence.

Purpose: To determine the association between the severity of trachomatous conjunctival scarring (TS) of the upper eyelid conjunctiva and trachomatous trichiasis (TT) severity in TT surgical patients.

Methods: A cross-sectional study was conducted amongst adults with TT who were referred to surgical camps in Bahi District, Tanzania, for TT surgery. Participants underwent ocular examination. The presence and severity of TS was evaluated in photographs of the everted upper eyelid. TT severity was assessed at the time of the ocular exam based on the number of lashes touching the globe and/or evidence and extent of epilation. Ordinal logistic models were used to examine the association between the severity of TS and TT severity.

Results: A total of 627 eyes of 388 participants were included. Mean age was 65 years (ranging from 21-98), 81% were females, and 62% had bilateral TT. 93% of eyes with any TT had at least moderate TS; 62% of eyes had severe TS. An increase in TS severity was associated with an increase in the severity of TT. Using as a reference eyes with none to mild TS, in eyes with moderate TS the odds of increased severity of TT was 1.30 (95% CI 0.67-2.51), in eyes with severe TS the odds was 4.20 (95% CI 2.23-7.92).

Conclusion: In cases of trachomatous trichiasis presenting for surgery, the severity of TT was significantly associated with the severity of TS with almost all cases of TT having moderate or severe scarring.

Purpose: Baseline surveys were conducted in Tigray region, Ethiopia, in 2013. Since then, rounds of azithromycin mass drug administration (MDA) have been delivered in-line with international guidance. The purpose of these surveys was to assess trachomatous inflammation-follicular (TF) prevalence following those treatments to enable the region to plan the next steps towards elimination of trachoma.

Methods: All surveys followed WHO recommendations for community-based cross-sectional survey design. Thirty-one woredas in six zones of Tigray region were surveyed. There were two survey series: all 31 woredas were surveyed in the first series, and 11 woredas were resurveyed in the second, due to having a TF prevalence between 5% and 9.9% in the first series.

Results: In the first series of 31 surveys, one woreda had an adjusted TF prevalence in 1-9-year-olds of <5.0%, 13 had a prevalence of 5.0-9.9% and 17 had a prevalence of 10.0-29.9%. In the second series of 11 surveys, the prevalence of TF was <5.0% in seven woredas and 5.0-9.9% in four woredas. The most recent adjusted prevalence of trachomatous trichiasis (TT) unknown to the health system in ≥15-year-olds was ≥.2% in 27 EUs. One-third of households visited had access to an improved drinking water source within a 30-minute return journey of their house, and 11% had an improved latrine.

Conclusion: Eight woredas met the criteria to stop MDA for 2 years before the re-survey. However, further rounds of MDA, additional efforts to improve water and sanitation access and ongoing strengthening of surgical services for TT are needed across Tigray.

Purpose: Trachoma is endemic in Kenya. Since baseline trachoma surveys in 2004, a concerted programme has been undertaken to reduce the prevalence of disease. Here, we report on trachoma prevalence surveys carried out between 2017 and 2020 after interventions were implemented in some areas for trachoma elimination purposes.

Methods: A total of 48 cross-sectional population-based trachoma prevalence surveys were conducted in 39 evaluation units (EUs; covering 45 subcounties) of Kenya between 2017 and 2020. Thirty EUs were surveyed once and nine EUs were surveyed twice over this period. Individuals ≥ 1 year old were assessed for trachomatous inflammation-follicular (TF), trachomatous inflammation-intense (TI) and trichiasis. Data were collected on household access to water, sanitation and hygiene (WASH).

Results: A total of 147,573 people were examined. At the end of 2020, in the 39 EUs surveyed, the prevalence of TF in 1-9-year-olds was ≥5% in 11 EUs and the prevalence of trichiasis unknown to the health system in individuals aged ≥15 years was ≥0.2% in 25 EUs. A small minority of households (median <50% for all indicators) had access to improved WASH facilities.

Conclusion: Kenya has made excellent progress towards elimination of trachoma as a public health problem. However, there is more work to do. Between one and three rounds of antibiotic mass drug administration are required in 11 EUs. Sustained investment in surgical provision, continued TT case-finding, promotion of facial cleanliness and environmental improvement are required throughout the surveyed area.

Introduction: Trichiasis is present when in-turned eyelashes touch the eyeball. It may result in permanent vision loss. Trachomatous trichiasis (TT) is caused by multiple rounds of inflammation associated with conjunctival Chlamydia trachomatis infection. Surveys have been designed to estimate the prevalence of TT in evaluation units (EUs) of trachoma-endemic countries in order to help develop appropriate programme-level plans. In this study, TT-only surveys were conducted in five EUs of The Gambia to determine whether further intensive programmatic action was required.

Methods: Two-stage cluster sampling was used to select 27 villages per EU and ~25 households per village. Graders assessed the TT status of individuals aged ≥15 years in each selected household, including the presence or absence of conjunctival scarring in those with TT.

Results: From February to March 2019, 11595 people aged ≥15 years were examined. A total of 34 cases of TT were identified. All five EUs had an age- and gender-adjusted prevalence of TT unknown to the health system <0.2%. Three of five EUs had a prevalence of 0.0%.

Conclusion: Using these and other previously collected data, in 2021, The Gambia was validated as having achieved national elimination of trachoma as a public health problem. Trachoma is still present in the population, but as its prevalence is low, it is unlikely that today's youth will experience the exposure to C. trachomatis required to precipitate TT. The Gambia demonstrates that with political will and consistent application of human and financial resources, trachoma can be eliminated as a public health problem.

Purpose: We aimed to estimate the prevalence of trachomatous inflammation-follicular (TF) in 1-9-year-olds and trachomatous trichiasis (TT) unknown to the health system in ≥15-year-olds in Benishangul Gumuz (BGZ) region, Ethiopia. This will help to assess progress towards the elimination of trachoma as a public health problem and determine the need for future interventions against trachoma in the region.

Methods: Cross-sectional population-based trachoma prevalence surveys were conducted in four evaluation units (EUs) of BGZ using World Health Organization-recommended survey methodologies. Individuals were examined for clinical signs of trachoma. Household access to water, sanitation and hygiene facilities (WaSH) was assessed.

Results: A total of 11,778 people aged ≥1 year were examined. The prevalence of TF in 1-9-year-olds was <5% in three EUs and ≥5% in one EU. The prevalence of TT unknown to the health system in people aged ≥15-years was ≥0.2% in all four EUs. The proportion of households with an improved drinking water source within a 30-minute round-trip ranged from 27-60%. The proportion of households with an improved latrine ranged from <1-6%.

Conclusions: Surgical interventions for TT are required in all EUs in BGZ. One annual round of mass drug administration (MDA) of azithromycin is required in one EU before resurvey to reassess progress in lowering TF prevalence below the WHO elimination threshold of 5% in 1-9-year-olds. MDA should be stopped in the other three EUs and trachoma surveillance surveys should be conducted at least 24 months after the surveys described here. Ongoing strengthening of WaSH infrastructure may help sustain the low prevalence of trachoma.

Purpose: To report the design of FLuorometholone as Adjunctive MEdical therapy for TT surgery (FLAME) trial.

Design: Parallel design, double-masked, placebo-controlled clinical trial with 1:1 randomization to fluorometholone 0.1% eye drops twice daily or placebo twice daily for 4 weeks in eyes undergoing trachomatous trichiasis (TT) surgery for assessing the efficacy, safety, and cost-effectiveness of fluorometholone 0.1% in preventing recurrent postoperative trichiasis (PTT).

Methods: Up to 2500 eligible persons with trachomatous trichiasis undergoing lid rotation surgery were enrolled in the Jimma zone, Ethiopia. Participants, surgeons, study field staff, and study supervisors leading operational aspects of the trial are masked to treatment assignment. Randomization is stratified by the surgeon and is simultaneously stratified by the district. Study visits (in addition to programmatic follow-ups) are at the baseline/enrollment, at four-week post-enrollment, and after 6 months and 1 year. The primary outcome is cumulative one-year PTT incidence, defined as: ≥1 lashes touching the globe, evidence of epilation, and/or repeat TT surgery. Secondary postoperative outcomes include the number of trichiatic lashes, location (touching the cornea or not), evidence of post-operative epilation, entropion, changes in corneal opacity, IOP elevation, need for cataract surgery, visual acuity change from the baseline, eyelid contour abnormality, granuloma, eyelid closure defect, and the occurrence of adverse events. Health economic analyses center on calculating the incremental cost per case of PTT avoided by fluorometholone treatment.

Conclusion: The FLAME Trial is designed to provide evidence of the efficacy, safety, and cost-effectiveness of adjunctive topical peri-/postoperative fluorometholone 0.1% therapy with trichiasis surgery, which is hypothesized to reduce the risk of recurrent trichiasis while being acceptably safe.

Clinical trial registration: https://www.clinicaltrials.gov/study/NCT04149210.

Purpose: To assess the change in eye health disparities due to trachoma using longitudinal country-level data (1990-2019) from the global burden of disease study 2019.

Methods:statement: We obtained data on the burden of trachoma and population statistics from the Global Health Data Exchange website. We assessed the geographic distribution of trachoma at the global level and World Bank regional level from year to year using Gini coefficients and statistics of inequality that ranged from 0 (total equality) to 1 (total inequality).

Result: We found that 60 countries and territories had a burden of trachoma, and these were from all regions except Central Europe, Eastern Europe, and Central Asia. At the global level, the Gini coefficient had increased from 0.546 to 0.637 (p for trend: <0.001) in the last three decades, while the mean disability-adjusted life years (DALYs) per 100,000 people declined from 13.0 to 3.2 (p for trend: <0.001). The inequality statistics had significantly worsened in South Asia and Sub-Saharan Africa (p for trend: <0.001) despite the decrease in the mean DALYs per capita.

Conclusion: Our study revealed that the burden of trachoma dramatically decreased; however, the eye health inequality due to trachoma increased globally and in two of the most endemic regions in the last three decades. Global eye health experts need to monitor the distribution of eye diseases and ensure appropriate, effective, uniform, and high-quality eye care for all.

Purpose: Trachoma is an eye disease caused by the bacterium Chlamydia trachomatis (Ct). It can lead to permanent vision loss. Since 2007, Burundi has included trachoma elimination as part of its fight against neglected tropical diseases and blindness. This study presents the results of trachoma baseline, impact and surveillance surveys conducted in Burundi between 2018 and 2021.

Methods: Areas were grouped into evaluation units (EU) with resident populations of between 100,000 and 250,000 people. Baseline surveys were conducted in 15 EUs, impact surveys in 2 EUs and surveillance surveys in 5 EUs; in each survey, 23 clusters of about 30 households were included. Consenting residents of those households were screened for clinical signs of trachoma. Access to water, sanitation and hygiene (WASH) was recorded.

Results: A total of 63,800 individuals were examined. The prevalence of TF in 1-9-year-olds was above the elimination threshold of 5% in a single EU at baseline, but fell below the threshold in subsequent impact and surveillance surveys. The prevalence of TT was below the 0.2% elimination threshold in ≥15-year-olds in all EUs surveyed. A high proportion (83%) of households had access to safe drinking water, while only a minority (~8%) had access to improved latrines.

Conclusion: Burundi has demonstrated the prevalence levels necessary for trachoma elimination status. With continued effort and the maintenance of existing management plans, trachoma elimination in Burundi is within reach.