463 results on '"West SK"'
Search Results
2. Correction: Short-term Forecasting of the Prevalence of Trachoma: Expert Opinion, Statistical Regression, versus Transmission Models.
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Lietman, Thomas, Liu, F, Porco, TC, Amza, A, Kadri, B, Nassirou, B, West, SK, Bailey, RL, Keenan, JD, Solomon, AW, and Emerson, PM
- Published
- 2015
3. Correction: The Distribution of Ocular Chlamydia Prevalence across Tanzanian Communities Where Trachoma Is Declining.
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Lietman, Thomas, Keenan, Jeremy, Porco, Travis, Rahman, SA, West, SK, Mkocha, H, Munoz, B, Porco, TC, Keenan, JD, and Lietman, TM
- Published
- 2015
4. Does Mass Azithromycin Distribution Impact Child Growth and Nutrition in Niger? A Cluster-Randomized Trial
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Keenan, Jeremy, Porco, Travis, Lietman, Thomas, Amza, A, Yu, SN, Kadri, B, Nassirou, B, Stoller, NE, Zhou, Z, West, SK, Bailey, RL, Gaynor, BD, and Keenan, JD
- Published
- 2014
5. The efficacy of oral azithromycin in clearing ocular chlamydia: Mathematical modeling from a community-randomized trachoma trial
- Author
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Porco, Travis, Lietman, Thomas, Liu, F, Porco, TC, Mkocha, HA, Muñoz, B, Ray, KJ, Bailey, RL, Lietman, TM, and West, SK
- Abstract
Mass oral azithromycin distributions have dramatically reduced the prevalence of the ocular strains of chlamydia that cause trachoma. Assessing efficacy of the antibiotic in an individual is important in planning trachoma elimination. However, the efficacy
- Published
- 2014
6. Assessment of Transmission in Trachoma Programs over Time Suggests No Short-Term Loss of Immunity
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Porco, Travis, Lietman, Thomas, Liu, F, Porco, TC, Ray, KJ, Bailey, RL, Mkocha, H, Muñoz, B, Quinn, TC, Lietman, TM, and West, SK
- Abstract
Trachoma programs have dramatically reduced the prevalence of the ocular chlamydia that cause the disease. Some have hypothesized that immunity to the infection may be reduced because of program success in reducing the incidence of infection, and transmiss
- Published
- 2013
7. The Easiest Children to Reach Are Most Likely to Be Infected with Ocular Chlamydia trachomatis in Trachoma Endemic Areas of Niger
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Lietman, Thomas, Keenan, Jeremy, McCulloch, Charles, Amza, A, Kadri, B, Nassirou, B, Yu, SN, Stoller, NE, Bhosai, SJ, Zhou, Z, McCulloch, CE, West, SK, and Bailey, RL
- Abstract
Background: Control programs for trachoma use mass antibiotic distributions to treat ocular Chlamydia trachomatis in an effort to eliminate this disease worldwide. To determine whether children infected with ocular Chlamydia are more likely to present late
- Published
- 2013
8. Association between Ocular Bacterial Carriage and Follicular Trachoma Following Mass Azithromycin Distribution in The Gambia
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Lietman, Thomas, Burr, SE, Hart, JD, Edwards, T, Baldeh, I, Bojang, E, Harding-Esch, EM, Holland, MJ, Lietman, TM, West, SK, and Mabey, DCW
- Abstract
Background:Trachoma, caused by ocular Chlamydia trachomatis infection, is the leading infectious cause of blindess, but its prevalence is now falling in many countries. As the prevalence falls, an increasing proportion of individuals with clinical signs of
- Published
- 2013
9. A cluster-randomized controlled trial evaluating the effects of mass azithromycin treatment on growth and nutrition in Niger
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Lietman, Thomas, Keenan, Jeremy, Porco, Travis, Amza, A, Kadri, B, Nassirou, B, Stoller, NE, Yu, SN, Zhou, Z, West, SK, Mabey, DCW, Bailey, RL, and Keenan, JD
- Abstract
Antimicrobials are used primarily to treat infectious disease, but they have other effects. Here, we assess anthropometry measurements in children 6-60 months in 24 communities randomized to one or two mass azithromycin distributions over a 1-year period i
- Published
- 2013
10. A Randomized Trial of Two Coverage Targets for Mass Treatment with Azithromycin for Trachoma
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Lietman, Thomas, Porco, Travis, West, SK, Bailey, R, Munoz, B, Edwards, T, Mkocha, H, Gaydos, C, Mabey, D, and Quinn, TC
- Abstract
Background:The World Health Organization recommends at least 3 annual antibiotic mass drug administrations (MDA) where the prevalence of trachoma is >10% in children ages 1-9 years, with coverage at least at 80%. However, the additional value of higher cov
- Published
- 2013
11. Four cases of acute comitant esotropia associated with diffuse intrinsic pontine glioma in children
- Author
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Osborne, D, primary, Richardson-May, J, additional, Bush, K, additional, Evans, M, additional, West, SK, additional, May, K, additional, and Self, J, additional
- Published
- 2022
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12. Four cases of acute comitant esotropia associated with diffuse intrinsic pontine glioma in children.
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Osborne, D, Richardson-May, J, Bush, K, Evans, M, West, SK, May, K, and Self, J
- Subjects
CONVERGENT strabismus ,GLIOMAS ,COVID-19 pandemic ,MAGNETIC resonance imaging ,EYE movements ,DIPLOPIA - Abstract
Acute acquired concomitant esotropia (AACE) is usually a benign form of strabismus that infrequently is associated with intracranial pathology. Clinicians have noted an increase in its incidence and theorize that it may be related to public health "lockdown" measures taken in response to the COVID-19 pandemic. With an increased incidence of AACE clinicians must firstly differentiate AACE from common accommodative esotropia and secondly recognize AACE as a possible sign of serious neuropathology. Diffuse Intrinsic Pontine Glioma (DIPG) is a devastating diagnosis for affected families. Children typically present at age 6-7 years with cranial nerve palsies, long tract signs, and/or cerebellar signs. Diagnosis is made from characteristic findings on magnetic resonance brain imaging (MRI brain) and treatment includes radiotherapy and palliative care. Two years from diagnosis, 90% of affected children will have died from their disease. We present four cases that attended our pediatric ophthalmology clinic with AACE either as a presenting sign of DIPG or as a clinical finding following a DIPG diagnosis. Patient A (age 5 years) presented to the emergency eye clinic with sudden onset diplopia and intermittent esotropia. Suppression later developed, they had 0.00 logMAR visual acuity either eye, and bilateral physiological hypermetropia. MRI brain imaging requested as a result of the unusual presentation led to the DIPG diagnosis. The other 3 cases (ages 11, 5 & 5 years) were assessed post DIPG diagnosis and found to have an esotropia measuring bigger on 1/3-meter fixation than 6-meter fixation, full ocular motility, physiological hypermetropia or emmetropia, and visual acuity normal for age. Other than patient B (age 11 years), who had papilledema and gaze evoked nystagmus when they were assessed 2 weeks prior to death, no patient had any other clinical eye findings. This small series of 4 patients attending our clinic within a 12-month period supports the notion that children presenting with AACE should routinely be offered brain MRI. Not all children with DIPG-associated AACE have significant ophthalmic findings indicative of intracranial pathology. With the potential for increased incidence of AACE related to lockdowns, clinicians should be reminded of the infrequent possibility their patient has a more serious condition. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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13. Visual impairment is treatable for many older patients and is more common in African Americans than whites
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Munoz, B, West, SK, and Rubin, GS
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Vision disorders -- Research ,Aged -- Health aspects ,Blindness -- Prevention ,Health ,Seniors - Abstract
More than one-half of older Americans with blindness or visual impairment have conditions that are surgically treatable or potentially preventable, according to researchers from Johns Hopkins University. They studied 2,520 [...]
- Published
- 2000
14. The heritability of age-related cortical cataract: the twin eye study
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Hammond, CJ, Duncan, DD, Snieder, H, de Lange, M, West, SK, Spector, TD, and Gilbert, CE
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genetic structures ,sense organs ,eye diseases - Abstract
PURPOSE: A classical twin study was performed to establish the relative importance of genes and environment in cortical cataract. METHODS: Five hundred six pairs of unselected female twin volunteers (226 monozygotic and 280 dizygotic) with a mean age of 62 years (range, 49-79 years) were examined. Cortical cataract was assessed using the slit-lamp-based Oxford Clinical Cataract Classification and Grading System (clinical grading) and the Wilmer Automated Grading System, which analyzed digital retroillumination images of subjects' lenses (digital grading). The worse eye categorized score for each individual was used in maximum likelihood path modeling of the correlations within twin pairs. These correlations were used to determine the underlying liability to cortical cataract. RESULTS: Prevalence of significant cortical cataract (>/=5% of lens area) was similar in monozygotic and dizygotic twins, occurring in 19.4% and 20.6% with the clinical grading system and 24% and 23% using the digital grading system, respectively. Modeling suggested liability to cortical cataract is explained by additive and dominant genes, individual environment, and age. Estimates of the broad sense heritability of cortical cataract were 58% (95% confidence interval [CI], 51%-64%) for the clinical grading system and 53% (95% CI, 45%-60%) for the digital system. Dominant genes were estimated to contribute to 38% (95% CI, 1%-64%) of the genetic effect with the clinical grading and 53% (95% CI, 28%-60%) with the digital grading. Individual environment explained 26% and 37% and age 16% and 11% of cortical cataract variance in clinical and digital gradings, respectively. CONCLUSIONS: Genetic effects are important in the development of cortical cataract and involve the action of dominant genes.
- Published
- 2001
15. Three-year outcomes of the surgery for trichiasis, antibiotics to prevent recurrence trial.
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Woreta F, Munoz B, Gower E, Alemayehu W, and West SK
- Published
- 2012
16. How much is not enough? A community randomized trial of a Water and Health Education programme for Trachoma and Ocular C. trachomatis infection in Niger.
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Abdou A, Munoz BE, Nassirou B, Kadri B, Moussa F, Baarè I, Riverson J, Opong E, West SK, Abdou, Amza, Munoz, Beatriz E, Nassirou, Baido, Kadri, Boubacar, Moussa, Fati, Baarè, Ibrahim, Riverson, Joseph, Opong, Emmanuel, and West, Sheila K
- Abstract
Summary Objective: To determine the impact after 2 years of a water and health education (W/HE) programme on ocular Chlamydia trachomatis infection and trachoma.Methods: We randomized 12 trachoma-endemic communities in Maradi, Niger 1:1 to W/HE intervention and control arms and collected data on 10 of the 12 villages. In the intervention villages, at least one clean water well was constructed, and a 3 month, modest health education programme was provided immediately prior to the 2 year survey. We censused all households, and 557 children ages 1-5 years were randomly selected as sentinel children and examined at baseline and at one and 2 years from baseline. Trachoma was clinically assessed and a swab taken and analyzed for C. trachomatis. Tetracycline eye ointment was provided to all children in either arm during the surveys who had signs of trachoma.Results: Infection with C. trachomatis declined slightly, and not significantly, in the children in the control villages over the 2 years, from 15% to 11%. The decline in infection was more pronounced, and significant, in the children in the intervention villages, from 26% to 15%. However, the change in infection rates in the intervention villages was not significantly different from the change in infection rates in the control villages (P = 0.39, and 0.11 for change from baseline to 1 year and 2 year, respectively). There was also no difference in the change in overall trachoma rates between the two arms.Conclusion: These data suggest that the provision of water plus a modest health education programme did not result in a significant difference in trachoma or ocular C. trachomatis infection in endemic communities in Niger. A more substantial health education intervention is likely necessary to produce change. [ABSTRACT FROM AUTHOR]- Published
- 2010
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17. Poor sense of direction is associated with constricted driving space in older drivers.
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Turano KA, Munoz B, Hassan SE, Duncan DD, Gower EW, Roche KB, Keay L, Munro CA, and West SK
- Abstract
The aims of this study were to determine whether perceived sense of direction was associated with the driving space of older drivers and whether the association was different between genders. Participants (1,425 drivers aged 67-87 years) underwent a battery of visual and cognitive tests and completed various questionnaires. Sense of direction was assessed using the Santa Barbara Sense of Direction (SBSOD) scale. Driving space was assessed by both the driving space component of the Driving Habits Questionnaire and log maximum area driven. Analyses were performed using generalized linear models. The SBSOD score was lower in women than in men and significantly associated with log driving area in women but not in men. The SBSOD score also showed a significant association with women's self-reported driving restriction. The findings emphasize the need to explore the role of psychological factors, and include gender, in driving studies and models. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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18. Low vision rehabilitation in a nursing home population: the SEEING study.
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Deremeik J, Broman AT, Friedman D, West SK, Massof R, Park W, Bandeen-Roche K, Frick K, and Muñoz B
- Abstract
As part of a study of 198 residents with low vision in 28 nursing homes, 91 participated in a low vision rehabilitation intervention. Among the rehabilitation participants, 78% received simple environmental modifications, such as lighting; 75% received low vision instruction; 73% benefited from staff training; and 69% received simple nonoptical devices. Because of the cognitive and physical fragility of many nursing home residents, the authors recommend an approach that centers on training nursing home staff and improving the environment of the facilities, especially in the area of illumination. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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19. Intensive insecticide spraying for fly control after mass antibiotic treatment for trachoma in a hyperendemic setting: a randomised trial.
- Author
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West SK, Emerson PM, Mkocha H, Mchiwa W, Munoz B, Bailey R, and Mabey D
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- 2006
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20. Infection with Chlamydia trachomatis after mass treatment of a trachoma hyperendemic community in Tanzania: a longitudinal study.
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West SK, Munoz B, Mkocha H, Holland MJ, Aguirre A, Solomon AW, Foster A, Bailey RL, Mabey DCW, West, Sheila K, Munoz, Beatriz, Mkocha, Harran, Holland, Martin J, Aguirre, Aura, Solomon, Anthony W, Foster, Allen, Bailey, Robin L, and Mabey, David C W
- Abstract
Background: Data from studies done in communities where trachoma is mesoendemic suggest that ocular infection with Chlamydia trachomatis can be eliminated after one mass treatment with antibiotics. However, there are no comparable long-term data from trachoma hyperendemic communities. Our aim, therefore, was two-fold: first, to ascertain the disease pattern of trachoma and ocular infection with C trachomatis in a trachoma hyperendemic community after mass treatment; and, second, to ascertain the risk factors for incident infection.Methods: We did a longitudinal study of a trachoma hyperendemic community (n=1017) in Tanzania. We did surveys, including ocular swabs, at baseline, 2, 6, 12, and 18 months to identify the presence, and quantity, of C trachomatis after single mass treatment of all individuals aged 6 months or older with azithromycin 20 mg per kg; pregnant women without clinical disease received topical tetracycline.Findings: Mass treatment (coverage 86%) significantly reduced the prevalence of infection from 57% (495 of 871) to 12% (85 of 705) at 2 months. Infection remained fairly constant to 12 months, with evidence of increasing numbers and load of infection by 18 months post-treatment. Incident infection at 6 months was 3.5-times more likely if another member of the household had more than 19 organisms per swab at 2 months. Travel outside the village, and visitors to the household, did not increase the risk of infection within households up to 12 months.Interpretation: In this trachoma hyperendemic community, infection levels after high antibiotic coverage persisted at a low level to 18 months, with evidence for re-emergence after 1 year. Fairly light loads of infection were associated with household transmission. Yearly mass treatment over a few years could be sufficient to eliminate infection. [ABSTRACT FROM AUTHOR]- Published
- 2005
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21. Culturally appropriate end-of-life care for the black American.
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West SK and Levi L
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- 2004
22. Diabetes and diabetic retinopathy in a Mexican-American population: Proyecto VER.
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West SK, Klein R, Rodriguez J, Muñoz B, Broman AT, Sanchez R, Snyder R, West, S K, Klein, R, Rodriguez, J, Muñoz, B, Broman, A T, Sanchez, R, Snyder, R, and Proyecto VER
- Abstract
Objectives: The prevalence rate of diabetes is probably higher in Hispanics than in Caucasians, although there is controversy about differences in the risk of diabetic retinopathy. The purpose of the study is to determine the prevalence rates of diabetes and diabetic retinopathy in a population-based study of Hispanics aged > or = 40 years.Research Design and Methods: Proyecto VER is a random sample of Hispanic populations aged > or = 40 years in Arizona. A total of 4,774 individuals (71.6% of the eligible sample) completed the examinations. Diabetes was defined as self-report of a physician diagnosis or HbA(1c) value of > or = 7.0%. Diabetic retinopathy was assessed on stereo fundus photographs of fields 1, 2, and 4.Results: The prevalence rate of diabetes in the Hispanic community (individuals > or = 40 years of age) was 22%. The prevalence rate of diabetic retinopathy (DR) was 48%; 32% had moderate to severe nonproliferative and proliferative retinopathy. DR increased with increasing duration of diabetes and increasing level of HbA(1c). The prevalence rate of DR-like changes in the sample of individuals without diabetic retinopathy was 15% and was not associated with hypertension, systolic blood pressure, or diastolic blood pressure.Conclusions: The prevalence rate of diabetes in this population of Hispanics is high, almost twice that of Caucasians. The prevalence rate of DR is high but similar to reports in a Caucasian population. The prevalence rate of 9% moderate to severe retinopathy in the newly diagnosed group suggests that efforts to improve detection and treatment of diabetes in Hispanics may be warranted. [ABSTRACT FROM AUTHOR]- Published
- 2001
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23. Sunlight exposure and risk of lens opacities in a population-based study: the Salisbury Eye Evaluation project.
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West SK, Duncan DD, Munoz B, Rubin GS, Fried LP, Bandeen-Roche K, Schein OD, West, S K, Duncan, D D, Muñoz, B, Rubin, G S, Fried, L P, Bandeen-Roche, K, and Schein, O D
- Abstract
Context: Exposure to UV-B radiation in sunlight has been shown to increase the risk of cataract formation in high-risk occupational groups, but risk to the population has not been quantified.Objectives: To determine the ocular exposure to UV-B radiation in sunlight for a population of older persons and to determine the association between UV-B and lens opacities.Design: The Salisbury Eye Evaluation project, a population-based cohort of older adults.Setting: Salisbury, Md.Participants: A total of 2520 community-dwelling 65-year-old to 84-year-old adults in Salisbury, Md, from 1993 to 1995, of whom 26.4% were African Americans.Main Outcome Measure: Association of photographically documented cortical opacity 3/16 or greater in at least 1 eye with ocular UV-B exposure, reported in Maryland sun-years of exposure.Results: The odds of cortical opacity increased with increasing ocular exposure to UV-B (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.02-1.20). The relationship was similar for women (OR, 1.14; 95% CI, 1.00-1.30) and for African Americans (OR, 1.18; 95% CI, 1.04-1.33). Analyses of the ocular dose by each age group after the age of 30 years showed no vulnerable age group, suggesting damage is based on cumulative exposure.Conclusions: Although this population of older Americans has relatively low ocular exposure to UV-B in sunlight, there is still an association between ocular exposure and increasing odds of cortical opacity. Our study found an association among African Americans, which, to our knowledge, has not been reported previously. All sex and racial groups would benefit from simple methods to avoid ocular sun exposure. [ABSTRACT FROM AUTHOR]- Published
- 1998
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24. A comprehensive assessment of visual impairment in a population of older Americans: the SEE study.
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West, SK, Munoz, B, Brandeen-Roche, K, Zeger, S, Schein, O, Fried, LP, Team, The See Project, and Rubin, GS
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- 1997
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25. Assessing functional status: correlation between performance on tasks conducted in a clinic setting and performance on the same task conducted at home. The Salisbury Eye Evaluation Project Team.
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West SK, Rubin GS, Munoz B, Abraham D, Fried LP, Salisbury Eye Evaluation Project Team, West, S K, Rubin, G S, Munoz, B, Abraham, D, and Fried, L P
- Abstract
Background: Many studies of functional status in elderly people use performance-based measures. There is an underlying assumption that these measures reflect, at least for some tasks, functional abilities in everyday tasks carried out at home. The purpose of this study was to determine the correlation between tasks carried out in the clinic and at home, and the role of visual impairment in performance at either setting.Methods: We compared the performance of 97 participants in the Salisbury Eye Evaluation (SEE) project at the clinic and at home on eight different tasks: semitandem stand, functional reach, stair climb and descend, inserting a plug, looking up and dialing a telephone number, and reading.Results: The correlations were good for all tasks, with coefficients ranging from .52 to .86. Those with visual impairment were slightly more likely to perform better at home compared to the clinic, although the differences were statistically significant only for the reading task. The most important predictor of performance on any task in the home was performance on the task at the clinic, even after adjusting for age, race, sex, education, and visual impairment. Educational level and visual impairment were consistent predictors of performance in the home for most tests.Conclusions: We conclude that performances on standardized tasks in the clinic setting do correlate with similar tasks performed in the home, although the relationship is complicated in the presence of visual impairment. [ABSTRACT FROM AUTHOR]- Published
- 1997
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26. A closer look.
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West SK
- Published
- 2007
27. Field evaluation of a rapid point-of-care assay for targeting antibiotic treatment for trachoma control: a comparative study.
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Michel CC, Solomon AW, Magbanua JPV, Massae PA, Huang L, Mosha J, West SK, Nadala ECB, Bailey R, Wisniewski C, Mabey DCW, and Lee HH
- Published
- 2006
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28. Re-emergence of Chlamydia trachomatis infection after mass antibiotic treatment of a trachoma-endemic Gambian community: a longitudinal study.
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Burton MJ, Holland MJ, Makalo P, Aryee EAN, Alexander NDE, Sillah A, Faal H, West SK, Foster A, Johnson GJ, Mabey DCW, Bailey RL, Burton, Matthew J, Holland, Martin J, Makalo, Pateh, Aryee, Esther A N, Alexander, Neal D E, Sillah, Ansumana, Faal, Hannah, and West, Sheila K
- Abstract
Background: Community-wide mass antibiotic treatment is a central component of trachoma control. The optimum frequency and duration of treatment are unknown. We measured the effect of mass treatment on the conjunctival burden of Chlamydia trachomatis in a Gambian community with low to medium trachoma prevalence and investigated the rate, route, and determinants of re-emergent infection.Methods: 14 trachoma-endemic villages in rural Gambia were examined and conjunctival swabs obtained at baseline, 2, 6, 12, and 17 months. Mass antibiotic treatment with azithromycin was given to the community at baseline. C trachomatis was detected by qualitative PCR and individual infection load then estimated by real-time quantitative PCR.Findings: C trachomatis was detected in 95 (7%) of 1319 individuals at baseline. Treatment coverage was 83% of the population (1328 of 1595 people). The effect of mass treatment was heterogeneous. In 12 villages all baseline infections (34 [3%] of 1062 individuals) resolved, and prevalence (three [0.3%]) and infection load remained low throughout the study. Two villages (baseline infection: 61 [24%] of 257 individuals) had increased infection 2 months after treatment (74 [30%]), after extensive contact with other untreated communities. Subsequently, this value reduced to less than half of that before treatment (25 [11%]).Interpretation: Mass antibiotic treatment generally results in effective, longlasting control of C trachomatis in this environment. For low prevalence regions, one treatment episode might be sufficient. Infection can be reintroduced through contact with untreated populations. Communities need to be monitored for treatment failure and control measures implemented over wide geographical areas. [ABSTRACT FROM AUTHOR]- Published
- 2005
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29. Mass treatment with single-dose azithromycin for trachoma.
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Solomon AW, Holland MJ, Alexander NDE, Massae PA, Aguirre A, Natividad-Sancho A, Molina S, Safari S, Shao JF, Courtright P, Peeling RW, West SK, Bailey RL, Foster A, Mabey DCW, Solomon, Anthony W, Holland, Martin J, Alexander, Neal D E, Massae, Patrick A, and Aguirre, Aura
- Abstract
Background: Trachoma, caused by repeated ocular infection with Chlamydia trachomatis, is an important cause of blindness. Current recommended dosing intervals for mass azithromycin treatment for trachoma are based on a mathematical model.Methods: We collected conjunctival swabs for quantitative polymerase-chain-reaction assay of C. trachomatis before and 2, 6, 12, 18, and 24 months after mass treatment with azithromycin in a Tanzanian community in which trachoma was endemic. For ethical reasons, at 6, 12, and 18 months, we gave tetracycline eye ointment to residents who had clinically active trachoma.Results: At baseline, 956 of 978 residents (97.8 percent) received either one oral dose of azithromycin or (if azithromycin was contraindicated) a course of tetracycline eye ointment. The prevalence of infection fell from 9.5 percent before mass treatment to 2.1 percent at 2 months and 0.1 percent at 24 months. The quantitative burden of ocular C. trachomatis infection in the community was 13.9 percent of the pretreatment level at 2 months and 0.8 percent at 24 months. At each time point after baseline, over 90 percent of the total community burden of C. trachomatis infection was found among subjects who had been positive the previous time they were tested.Conclusions: The prevalence and intensity of infection fell dramatically and remained low for two years after treatment. One round of very-high-coverage mass treatment with azithromycin, perhaps aided by subsequent periodic use of tetracycline eye ointment for persons with active disease, can interrupt the transmission of ocular C. trachomatis infection. [ABSTRACT FROM AUTHOR]- Published
- 2004
30. Strategies for control of trachoma: observational study with quantitative PCR.
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Solomon AW, Holland MJ, Burton MJ, West SK, Alexander NDE, Aguirre A, Massae PA, Mkocha H, Muñoz B, Johnson GJ, Peeling RW, Bailey RL, Foster A, and Mabey DCW
- Published
- 2003
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31. Nutrient intakes and adequacy among an older population on the eastern shore of Maryland: the Salisbury Eye Evaluation.
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Cid-Ruzafa J, Caulfield LE, Barron Y, and West SK
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- 1999
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32. Model of yearly transition to severe trachomatous scarring and trichiasis in a cohort of women in Kongwa Tanzania.
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West SK, Hazel A, Munoz B, Wolle MA, Mkocha H, and Porco TC
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- Humans, Tanzania epidemiology, Female, Adult, Prevalence, Disease Progression, Adolescent, Young Adult, Incidence, Longitudinal Studies, Child, Middle Aged, Cohort Studies, Trachoma epidemiology, Cicatrix epidemiology, Trichiasis epidemiology
- Abstract
One criterion for validation of trachoma elimination is the management of Trachomatous Trichiasis (TT) after Trachoma inflammation-follicular (TF) is eliminated in children ages 1-9 years at district level. No data exist on how long countries must have dedicated TT programs, as the timeline for progression to TT from trachomatous scarring is unknown. We used eight years of longitudinal data in women in Kongwa Tanzania to model progression from no scarring (S0) through grades of scarring severity (S1-S4) to TT. Markov models were used, with age, community prevalence of TF (CPTF), and household characteristics as co-variates. Adjusted for covariates, the incidence of S1 was estimated at 4∙7% per year, and the risk increased by 26% if the CPTF was between 5-10% and by 48% if greater than 10%. The transition from S4 to TT was estimated at 2∙6% per year. Districts, even after elimination of TF, may have some communities with TF ≥ 5% and increased risk of incident scarring. Once scarring progresses to S2, further progression is not dependent on CPTF. These data suggest that, depending on the district level of scarring and degree of heterogeneity in CPTF at the time of elimination, incident TT will still be an issue for decades., (© 2024. The Author(s).)
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- 2024
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33. Severity of Trachomatous Scarring among Adults in Trachoma-Endemic Amhara Region of Ethiopia.
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Bromfield JA, Aguwa UT, Sata E, Jensen KA, Mihretu F, Callahan EK, West SK, Wolle MA, and Nash SD
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Trachomatous scarring has been shown to progress regardless of active ocular Chlamydia trachomatis infection, indicating that scarring drivers may be unrelated to ongoing transmission. Although scarring prevalence is commonly associated with older age and female sex, less is known about other potential contributors to its development. This study identified and assessed risk factors associated with scarring magnitude in a trachoma-endemic setting, utilizing a five-point photographic scale (S0-S4). During 2017 trachoma surveys of Amhara, Ethiopia, photographers captured left and right conjunctival images of adults (ages 15 years and older) from 10 districts. Subsequently, two graders independently assessed photographs for scarring, with discrepancies adjudicated by an expert grader. Scarring scores for 729 individuals were aggregated from the eye level to the participant level, excluding 17 participants because of poor photograph quality. Among those with scarring, most cases (20.4%) were severe (S4, comprising more than 90% of the tarsal conjunctiva) compared with the prevalence of moderate S3-A/B (11.2%), S2 (8.3%), and mild S1 (19.2%). The youngest group (ages 15-19 years) exhibited all scarring stages. Older participants (60 years and older) experienced a greater burden of severe scarring (S4 prevalence: 32.6%) than their younger (15-19 years) counterparts (6.2%). Multivariate ordinal logistic regression models indicated female sex, increasing age, and district-level trachomatous follicular-inflammation prevalence were significant predictors of scarring severity. Trachomatous scarring and its progression to trichiasis, may prove a barrier to meeting WHO timelines for trachoma elimination and will necessitate ongoing surveillance and interventions after elimination thresholds have been met.
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- 2024
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34. Validation of a New Duplex Real-Time Polymerase Chain Reaction for Chlamydia trachomatis DNA Detection in Ocular Swab Samples.
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Favacho JDFR, Leite KK, Jacomasso T, Farias AB, Franco Filho LC, Gomes STM, Dos Reis HS, Mota GD, Schluga PHC, Tassi WS, Rampazzo RCP, West SK, Gaydos CA, da Cunha AJLA, and Costa ADT
- Abstract
Trachoma is the world-leading infectious cause of preventable blindness and is caused by the bacteria Chlamydia trachomatis . In developing countries, diagnosis is usually based on clinical evaluation. Serological-based tests are cheaper than molecular-based ones, but the latter are more sensitive and specific. The present study developed a new duplex qPCR which concomitantly detects the C. trachomatis cryptic plasmid and the human 18S rRNA gene, with an LOD95% for C. trachomatis DNA of 13.04 genome equivalents per reaction. The new qPCR was tested using 50 samples from an endemic area and 12 from a non-endemic area that were previously characterized using direct immunofluorescence assay (DFA) and clinical evaluation. Among the 50 endemic samples, 3 were found to be positive by clinical evaluation (6%), 18 were found to be positive by DFA (36%), and 48 were found to be positive by qPCR (96%). Next, the new duplex qPCR was validated using 50 samples previously characterized by qPCR. Validation was carried out on a benchtop instrument (ABI7500) or on a portable point-of-care instrument (Q3-Plus), showing 95% specificity and 100% sensitivity. The ubiquitous presence of C. trachomatis DNA in samples from the endemic region confirms that constant monitoring is of paramount importance for the effective measurement of the elimination of trachoma. The newly developed duplex qPCR presented in this study, along with its validation in a portable qPCR system, constitutes important tools toward achieving this goal.
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- 2024
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35. Comparison of two approaches to measuring clean faces as part of the facial cleanliness component of the SAFE trachoma elimination strategy.
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West SK, Munoz B, Mkocha H, Lynch MC, Gracewello C, Kasubi M, and Wolle MA
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- Humans, Child, Preschool, Tanzania epidemiology, Infant, Female, Male, Child, Reproducibility of Results, Trachoma prevention & control, Face, Hygiene standards
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Background: The Alliance for the Global Elimination of Trachoma (GET) endorses the full SAFE strategy to eliminate trachoma; Surgery (for trichiasis), Antibiotics (to reduce the community pool of infection, Facial cleanliness, and Environmental improvement (to decrease transmission). There is no accepted measure of facial cleanliness. This study compared two possible metrics for facial cleanliness., Method/findings: Metric one: Clean face was defined as observed absence of ocular and nasal discharge on the face. Metric two: observing a grade of dirtiness (scale 10 = lightest to 0 = darkest) on a standard facial wipe. The reliability of grading a child's face or grading a facial wipe was determined in children in Kongwa Tanzania. We also observed both measurements in a cohort of 202 children ages 1 to <7years prior to face cleaning, immediately afterwards, and 4 hours afterwards. Fifty of the children did not have face cleaning and were controls. Intra-and interobserver reliability was similar for both measures, the latter = 0.53 for observing a clean face and 0.52 for grading a facial wipe. There was no correlation between the two. Both measures detected facial cleaning, compared to control children who were not cleaned, immediately after cleaning; control children with 53% clean faces and wipe score of 6.7 compared to cleaned children with 88% clean faces and wipe score of 8 (p = .0001, p = < .0001, respectively). Both measures also detected face washing 4 hours previously compared to controls., Conclusions: The two metrics were equally reliable, and both measured the behavior of face washing. They measure different aspects of a clean face; one measures the amount of dirt on wiped area and the other measures ocular and nasal discharge. Both measurements appear to capture the behavior of facial cleaning, and the choice of metric would appear to rest on the measurement that captures the stated objective of the behavior, consideration of costs, training, logistics, and implementation., Competing Interests: None of the authors report any competing interests that could be perceived to bias this work., (Copyright: © 2024 West et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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36. Efficacy of Single-Dose Azithromycin for Ocular Chlamydial Infection: A Longitudinal Study.
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Pondicherry N, Abdou A, Kadri B, Nassirou B, Cotter SY, Varnado NE, Porco TC, West SK, Lietman TM, and Keenan JD
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- Humans, Child, Preschool, Infant, Female, Male, Longitudinal Studies, Treatment Outcome, Chlamydia Infections drug therapy, Niger, Infant, Newborn, Azithromycin administration & dosage, Azithromycin therapeutic use, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents therapeutic use, Trachoma drug therapy, Chlamydia trachomatis drug effects
- Abstract
Millions of doses of azithromycin are distributed each year for trachoma, yet the treatment efficacy of a single dose of azithromycin for ocular Chlamydia infection has not been well characterized. In this study, four villages in Niger received a mass azithromycin distribution for trachoma. All 426 children aged 0-5 years residing in the study villages were offered conjunctival swabbing every 6 months to test for ocular Chlamydia trachomatis. Among the children infected with ocular Chlamydia before treatment, 6% (95% CI: 2-15%) tested positive for ocular Chlamydia infection 6 months later, and 15% (95% CI: 7-28%) tested positive 12 months later. The most important predictor of post-treatment ocular Chlamydia infection was pretreatment ocular Chlamydia infection (relative risk: 3.5, 95% CI: 1.3-9.4). Although the 6-monthly monitoring schedule was suboptimal for testing the treatment efficacy of an antibiotic, these findings are nonetheless consistent with high treatment efficacy of a single dose of azithromycin and suggest that additional interventions might be most effective if targeted to those children infected prior to treatment.
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- 2024
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37. Gender differences in trachomatous scarring prevalence in a formerly trachoma hyperendemic district in Tanzania.
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Wolle MA, Muñoz BE, Mgboji G, Naufal F, Kashaf MS, Mkocha H, and West SK
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- Male, Adult, Humans, Female, Adolescent, Tanzania epidemiology, Cicatrix epidemiology, Prevalence, Cross-Sectional Studies, Sex Factors, Chlamydia trachomatis, Trachoma epidemiology, Trachoma complications, Trichiasis epidemiology
- Abstract
Background: Trachoma is a chronic conjunctivitis caused by the bacterium Chlamydia trachomatis. Repeated infections lead to trachomatous conjunctival scarring which can progress to potentially blinding trachomatous trichiasis (TT). In trachoma hyperendemic conditions, women compared to men have an increased risk of scarring and TT, which can progress to blinding corneal opacification. This study determined if there were gender differences in scarring prevalence and severity when trachoma prevalence approaches elimination, in a formerly trachoma hyperendemic region., Methodology/principal Findings: A cross-sectional prevalence study was conducted amongst adults age 15 years and older in Kongwa district, Tanzania in 2019. 3168 persons over age 15 years agreed to be examined and had at least one eye with a gradable image. Ocular photographs were graded for scarring according to a published four-step severity scale. Overall, about half of all study participants had scarring. However, more females (52.3%) had any scarring compared to males (47.2%), OR = 1.22 (95% CI = 1.05-1.43). For every year increase in age, there was a 6.5% increase in the odds of having more severe scarring (95% CI: 5.8%, 7.2%). Women were more likely than men to have severe scarring, OR 2.36 (95% CI: 1.84-3.02). Residence in a community with TF≥10% was associated with a 1.6-fold increased odds of any scarring., Conclusions/significance: Overall scarring prevalence and more severe scarring prevalence was higher in females compared to males, even adjusting for age and community TF prevalence. The data suggest that processes occur that lead to women preferentially progressing towards more severe scarring compared to men., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wolle et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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38. Expanding a photographic grading system for trachomatous scarring.
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Nayel Y, Muñoz BE, Mkocha H, West SK, and Wolle MA
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- Adult, Humans, Female, Reproducibility of Results, Photography, Tanzania, Cicatrix, Trachoma
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Background: The purpose was to assess an expansion of a previously published photographic four-step severity grading scale for trachomatous scarring (TS)., Methods: Images of everted eyelids of adult women in Tanzania were graded for the presence and severity of TS. The previous S3 grade was subdivided into two categories: S3A, one-third to <50% of the upper eyelid conjunctiva scarred; and S3B, 50% to <90%. The reliability and ease of use were evaluated. This new categorisation was then applied to images taken of the same women 5 y prior to evaluate whether it could help detect previously undetected progression., Results: In total, 142 eyes at baseline and 418 eyes at follow-up after 5 y were graded as S3. Interobserver agreement using the expanded scarring grading scale was a kappa of 0.86. At baseline, 51 (35.9%) eyes were S3A and 91 (64.1%) were S3B. At follow-up after 5 y, 36.6% of the eyes that were previously documented as not having progressed were now detected as having progressed from S3A to S3B. S3B images were more likely to progress to S4 compared with S3A (OR 4.6, 95% CI 2.1 to 9.9)., Conclusions: Adding S3A and S3B is reliable and detects more scarring progression. It will be beneficial for future studies analysing TS in photographs., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)
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- 2023
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39. Comparing image quality and trachoma detection across three camera types from a survey in Kongwa, Tanzania.
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Aguwa UT, Mkocha H, Munoz B, Wolle MA, Brady CJ, and West SK
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- Child, Humans, Tanzania epidemiology, Smartphone, Trachoma diagnostic imaging, Trachoma epidemiology
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Background: There is an increasing demand for photography for trachoma prevalence surveys. In previous studies, digital single lens reflex (DSLR) images were superior to smartphone images, but newer-model smartphones and/or lens attachments may be able to bridge this gap. This study compares the image quality and ability to detect trachomatous inflammation - follicular (TF) of three camera types: a DSLR Nikon camera, an iPhone SE and an iPhone 13 Pro with a cell scope., Methods: We surveyed 62 children ages 1-7 y from two Tanzanian communities. Upper tarsal conjunctiva images of both eyes were graded for TF by two standardized graders. The McNemar's test and a logistic regression model were used for analyses., Results: The DSLR camera malfunctioned during the study, thus the iPhone SE and iPhone 13 Pro with cell scope were both more likely to take high-quality, gradable photographs (88% and 86%, respectively) compared with the DSLR camera (69%) (p<0.001 and p=0.02, respectively). TF was detected in gradable images from the iPhone SE (8.8%) and iPhone 13 Pro with cell scope (9.0%) at the same rate (p=1.0) as images from the DSLR camera (9.7%)., Conclusion: Smartphones with high-quality image capture, like the iPhone SE/13 Pro, have the potential for use in trachoma surveys if the proportion of gradable images can be improved., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)
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- 2023
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40. Relationship Between Intraocular Pressure and Age: A Population-Based Study in Nepal.
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Bhandari G, Bhandari S, Byanju R, Pradhan S, Sah RK, Kandel RP, Thompson IJ, Rotchford AP, West SK, Muñoz B, Stevens VM, Oatts JT, Ou Y, Lietman TM, O'Brien KS, and Keenan JD
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- Adult, Humans, Middle Aged, Aged, Aged, 80 and over, Cross-Sectional Studies, Nepal epidemiology, Tonometry, Ocular methods, Intraocular Pressure, Glaucoma diagnosis, Glaucoma epidemiology
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Prcis: Intraocular pressure (IOP) decreased with age in a population-based study in Nepal, from a mean of 14.1 mm Hg among those 60-64 years old to 13.0 mm Hg among those 80 years old or older., Purpose: Few studies have assessed the distribution of IOP from the Indian subcontinent, despite its large population and high burden of glaucoma. The objective of this study was to assess the distribution of IOP measurements from adults living in a lowland region of Nepal., Methods: In a population-based cross-sectional study, all individuals aged 60 years and older from an area of lowland Nepal were invited for an IOP assessment with a rebound tonometer., Results: Of 160 communities (28,672 people aged ≥60 y) enrolled, 79 (13,808 people aged ≥60 y) were randomly selected for IOP testing. Of those eligible, 10,017 (72.5%) individuals underwent tonometry. Mean IOP decreased monotonically over 5-year age groups, from 14.1 mm Hg (SD: 3.6) among those aged 60-64 years to 13.0 mm Hg (SD: 4.2) among those 80 years or older. The 97.5th percentile IOP measurement was 21.0 mm Hg for all age groups. In adjusted analyses, younger age, self-reported diabetes, and higher population density were each associated with higher IOP, and self-reported cataract surgery was associated with lower IOP., Conclusions: Mean IOP was lower among older individuals in Nepal, consistent with many studies from East Asia and in contrast to many studies from western populations. These results suggest that ethnic background might be a consideration when diagnosing ocular hypertension., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2023
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41. The Association Between the Severity of Trachomatous Scarring and Trachomatous Trichiasis Severity in Surgical Patients in Tanzania.
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Wolle MA, Misra N, Naufal F, Saheb Kashaf M, Munoz BE, Mkocha H, Funga N, and West SK
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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.
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- 2023
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42. Monitoring transmission intensity of trachoma with serology.
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Tedijanto C, Solomon AW, Martin DL, Nash SD, Keenan JD, Lietman TM, Lammie PJ, Aiemjoy K, Amza A, Aragie S, Arzika AM, Callahan EK, Carolan S, Dawed AA, Goodhew EB, Gwyn S, Hammou J, Kadri B, Kalua K, Maliki R, Nassirou B, Seife F, Tadesse Z, West SK, Wittberg DM, Zeru Tadege T, and Arnold BF
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- Child, Humans, Infant, Child, Preschool, Seroepidemiologic Studies, Antigens, Bacterial, Antibodies, Bacterial, Chlamydia trachomatis, Prevalence, Trachoma diagnosis, Trachoma epidemiology
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Trachoma, caused by ocular Chlamydia trachomatis infection, is targeted for global elimination as a public health problem by 2030. To provide evidence for use of antibodies to monitor C. trachomatis transmission, we collated IgG responses to Pgp3 antigen, PCR positivity, and clinical observations from 19,811 children aged 1-9 years in 14 populations. We demonstrate that age-seroprevalence curves consistently shift along a gradient of transmission intensity: rising steeply in populations with high levels of infection and active trachoma and becoming flat in populations near elimination. Seroprevalence (range: 0-54%) and seroconversion rates (range: 0-15 per 100 person-years) correlate with PCR prevalence (r: 0.87, 95% CI: 0.57, 0.97). A seroprevalence threshold of 13.5% (seroconversion rate 2.75 per 100 person-years) identifies clusters with any PCR-identified infection at high sensitivity ( >90%) and moderate specificity (69-75%). Antibody responses in young children provide a robust, generalizable approach to monitor population progress toward and beyond trachoma elimination., (© 2023. The Author(s).)
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- 2023
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43. The Impact of Neighborhood Factors on Physical Activity in Older Adults With Visual Impairment.
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Garzon C, Mihailovic A, E JY, West SK, Gitlin LN, Friedman DS, and Ramulu PY
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- Humans, Male, Aged, Middle Aged, Female, Cross-Sectional Studies, Visual Fields, Visual Acuity, Exercise, Vision Disorders epidemiology, Vision Disorders complications, Vision, Low, Glaucoma complications
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Purpose: To investigate the associations of neighborhood-level socioeconomic and environmental characteristics with physical activity in persons with glaucoma., Design: Cross-sectional study (N = 230)., Methods: Home addresses were used to extract neighborhood factors (NFs): Area Deprivation Index, crime rate, and the proportion of racial and ethnic minorities, poverty, college graduates, and park area in their census tract. Participants' average number of daily steps and nonsedentary minutes were collected over 7 days using an accelerometer. Visual field (VF) loss was quantified as integrated VF sensitivity. Multivariable negative binomial regression models and additional models with an interaction term evaluated the effect of NF on physical activity and whether these relationships differed by VF loss severity., Results: Participants were on average 70.6 years of age, 51.7% were male, and 27.8% were black. A higher Area Deprivation Index or poverty share was associated with fewer NSM (incidence rate ratio [IRR] = 0.96 per 1 Area Deprivation Index decile increment, P = .01; IRR = 0.92 per 10% poverty share increment, P = .02), while higher share of college graduates was associated with greater NSM (IRR = 1.03 per 10% increment; P = .03). Stronger associations were noted between both high crime rate and poverty share with NSM in individuals with severe VF damage as opposed to no/mild VF damage (IRR = 0.44, P = .001; IRR = 0.81, P = .02)., Conclusions: Select NFs (poverty share and crime rate) may disproportionately affect physical activity in patients with severe VF loss. Interventions to overcome activity limitations within the context of poverty and high socioeconomic disadvantage are important for addressing glaucoma-related disability, particularly in those with severe VF loss., (Copyright © 2023 Elsevier Inc. All rights reserved.)
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- 2023
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44. Association of Optic Nerve Head and Macular Optical Coherence Tomography Measures With Glaucoma-Related Disability.
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Bonham LW, Mihailovic A, Xiao G, West SK, Friedman DS, and Ramulu PY
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- Humans, Tomography, Optical Coherence methods, Quality of Life, Cross-Sectional Studies, Accidental Falls, Retinal Ganglion Cells, Intraocular Pressure, Nerve Fibers, Fear, Optic Disk, Glaucoma complications, Glaucoma diagnosis
- Abstract
Prcis: Optical coherence tomography (OCT) estimated retinal nerve fiber layer (RNFL) thickness associated with glaucoma-related disability independent of the visual field (VF) damage and thus may provide additional patient-relevant disability information beyond what is captured by standard VF testing., Purpose: To examine whether OCT metrics [peripapillary RNFL thickness and macular ganglion cell/inner plexiform layer (GCIPL) thickness] are associated with quality of life (QoL) measures and additional disability metrics, and whether these associations are independent of VF damage., Methods: In this cross-sectional study, 156 patients with glaucoma or suspected glaucoma received VF testing and OCT scans to measure RNFL and GCIPL thickness. QoL was assessed using the Glaucoma Quality-of-Life 15 and additional disability measures including fear of falling, reading speed, and steps per day were assessed. Multivariable regression models adjusting for relevant covariates tested whether RNFL or GCIPL thickness from the less-impaired eye were associated with disability measures and whether associations were independent of VF damage., Results: Greater VF damage is associated with worse QoL (95% CI=0.4-1.4; P <0.001) and slower reading speed (CI=-0.06 to -0.02; P <0.001). Lower RNFL and GCIPL thicknesses were associated with lower QoL scores, but not with QoL scores or other disability metrics after correcting for VF damage. However, post hoc analyses in patients with better eye thicknesses between 55 and 75 µm demonstrated associations between lower RNFL thickness and worse QoL (CI=-2.2 to -0.1; P =0.04) and greater fear of falling (CI=-6.1 to -0.4; P =0.03) even after accounting for VF damage. No such associations were observed for GCIPL thickness., Conclusions: OCT RNFL, but not GCIPL, thickness is associated with multiple disability measures independent of VF damage severity., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2023
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45. A Virtual Reading Center Model Using Crowdsourcing to Grade Photographs for Trachoma: Validation Study.
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Brady CJ, Cockrell RC, Aldrich LR, Wolle MA, and West SK
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- Humans, Photography methods, Prevalence, Crowdsourcing methods, Telemedicine methods, Trachoma diagnosis
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Background: As trachoma is eliminated, skilled field graders become less adept at correctly identifying active disease (trachomatous inflammation-follicular [TF]). Deciding if trachoma has been eliminated from a district or if treatment strategies need to be continued or reinstated is of critical public health importance. Telemedicine solutions require both connectivity, which can be poor in the resource-limited regions of the world in which trachoma occurs, and accurate grading of the images., Objective: Our purpose was to develop and validate a cloud-based "virtual reading center" (VRC) model using crowdsourcing for image interpretation., Methods: The Amazon Mechanical Turk (AMT) platform was used to recruit lay graders to interpret 2299 gradable images from a prior field trial of a smartphone-based camera system. Each image received 7 grades for US $0.05 per grade in this VRC. The resultant data set was divided into training and test sets to internally validate the VRC. In the training set, crowdsourcing scores were summed, and the optimal raw score cutoff was chosen to optimize kappa agreement and the resulting prevalence of TF. The best method was then applied to the test set, and the sensitivity, specificity, kappa, and TF prevalence were calculated., Results: In this trial, over 16,000 grades were rendered in just over 60 minutes for US $1098 including AMT fees. After choosing an AMT raw score cut point to optimize kappa near the World Health Organization (WHO)-endorsed level of 0.7 (with a simulated 40% prevalence TF), crowdsourcing was 95% sensitive and 87% specific for TF in the training set with a kappa of 0.797. All 196 crowdsourced-positive images received a skilled overread to mimic a tiered reading center and specificity improved to 99%, while sensitivity remained above 78%. Kappa for the entire sample improved from 0.162 to 0.685 with overreads, and the skilled grader burden was reduced by over 80%. This tiered VRC model was then applied to the test set and produced a sensitivity of 99% and a specificity of 76% with a kappa of 0.775 in the entire set. The prevalence estimated by the VRC was 2.70% (95% CI 1.84%-3.80%) compared to the ground truth prevalence of 2.87% (95% CI 1.98%-4.01%)., Conclusions: A VRC model using crowdsourcing as a first pass with skilled grading of positive images was able to identify TF rapidly and accurately in a low prevalence setting. The findings from this study support further validation of a VRC and crowdsourcing for image grading and estimation of trachoma prevalence from field-acquired images, although further prospective field testing is required to determine if diagnostic characteristics are acceptable in real-world surveys with a low prevalence of the disease., (©Christopher J Brady, R Chase Cockrell, Lindsay R Aldrich, Meraf A Wolle, Sheila K West. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 06.04.2023.)
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- 2023
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46. Comparison of Five Camera Systems for Capturing and Grading Trachoma Images.
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Naufal F, Brady CJ, Muñoz B, Mkocha H, and West SK
- Abstract
Purpose: As training of trachoma graders using live participants grows increasingly difficult and expensive, alternative ways are needed possibly through replacement of field grading with photography. However, minimum specifications for a camera system capable of capturing high quality images have not been defined. This study compared images captured using four smartphones with those from a Nikon SLR camera for image quality and assessment of trachomatous inflammation - follicular (TF)., Methods: The smartphones - Samsung Galaxy S8 (S8), Techno Camon 17 pro (TC), Infinix Note 10 pro (IN), Huawei p30 pro (HP) - were chosen for their availability and likelihood of good performance based on specifications without external attachments. All smartphones were used in random order for each participant., Results: 129 children in Kongwa, Tanzania were enrolled (32.8% TF prevalence). The SLR camera had the least percent of ungradable images (3.1%), followed by the S8 (14%), HP (23.4%), IN (65.9%), and TC (71.2%). The S8 and the HP were significantly more likely to take ungradable images if they were used toward the end of the camera rotation. Agreement between the SLR and field grade was kappa = 0.73. Agreement between the field grade and gradable images from the S8 (0.68) and HP (0.8) was measured., Conclusions: Published specifications did not predict the success of using different smartphones for everted eyelid photographs; proprietary post-processing software likely influenced gradeability. Smartphones, though we cannot recommend those tested in this study, may be viable for capturing images for trachoma provided the quality of images from the field are adequate.
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- 2023
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47. Detection of trachoma using machine learning approaches.
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Socia D, Brady CJ, West SK, and Cockrell RC
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- Humans, Artificial Intelligence, Machine Learning, Neural Networks, Computer, Predictive Value of Tests, Trachoma diagnosis
- Abstract
Background: Though significant progress in disease elimination has been made over the past decades, trachoma is the leading infectious cause of blindness globally. Further efforts in trachoma elimination are paradoxically being limited by the relative rarity of the disease, which makes clinical training for monitoring surveys difficult. In this work, we evaluate the plausibility of an Artificial Intelligence model to augment or replace human image graders in the evaluation/diagnosis of trachomatous inflammation-follicular (TF)., Methods: We utilized a dataset consisting of 2300 images with a 5% positivity rate for TF. We developed classifiers by implementing two state-of-the-art Convolutional Neural Network architectures, ResNet101 and VGG16, and applying a suite of data augmentation/oversampling techniques to the positive images. We then augmented our data set with additional images from independent research groups and evaluated performance., Results: Models performed well in minimizing the number of false negatives, given the constraint of the low numbers of images in which TF was present. The best performing models achieved a sensitivity of 95% and positive predictive value of 50-70% while reducing the number images requiring skilled grading by 66-75%. Basic oversampling and data augmentation techniques were most successful at improving model performance, while techniques that are grounded in clinical experience, such as highlighting follicles, were less successful., Discussion: The developed models perform well and significantly reduce the burden on graders by minimizing the number of false negative identifications. Further improvements in model skill will benefit from data sets with more TF as well as a range in image quality and image capture techniques used. While these models approach/meet the community-accepted standard for skilled field graders (i.e., Cohen's Kappa >0.7), they are insufficient to be deployed independently/clinically at this time; rather, they can be utilized to significantly reduce the burden on skilled image graders., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Socia et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2022
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48. An observational assessment of the safety of mass drug administration for trachoma in Ethiopian children.
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Ciciriello AM, Addiss DG, Teferi T, Emerson PM, Hooper PJ, Seid M, Tadesse G, Seife F, Sormolo MJ, Kebede F, Kiflu G, West SK, Alemu M, LaCon G, and Gebre T
- Subjects
- Adult, Anti-Bacterial Agents adverse effects, Azithromycin adverse effects, Child, Ethiopia epidemiology, Humans, Infant, Mass Drug Administration, Powders therapeutic use, Airway Obstruction drug therapy, Trachoma drug therapy, Trachoma epidemiology
- Abstract
Background: The International Trachoma Initiative (ITI) provides azithromycin for mass drug administration (MDA) to eliminate trachoma as a public health problem. Azithromycin is given as tablets for adults and powder for oral suspension (POS) is recommended for children aged <7 y, children <120 cm in height (regardless of age) or anyone who reports difficulty in swallowing tablets. An observational assessment of MDA for trachoma was conducted to determine the frequency with which children aged 6 mo through 14 y received the recommended dose and form of azithromycin according to current dosing guidelines and to assess risk factors for choking and adverse swallowing events (ASEs)., Methods: MDA was observed in three regions of Ethiopia and data were collected on azithromycin administration and ASEs., Results: A total of 6477 azithromycin administrations were observed; 97.9% of children received the exact recommended dose. Of children aged 6 mo to <7 y or <120 cm in height, 99.6% received POS. One child experienced choking and 132 (2%) experienced ≥1 ASEs. Factors significantly associated with ASEs included age 6-11 mo or 1-6 y, non-calm demeanor and requiring coaxing prior to drug administration., Conclusions: There is a high level of adherence to the revised azithromycin dosing guidelines and low incidence of choking and ASEs., (© The Author(s) 2022. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)
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- 2022
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49. Advance Care Directive Preferences in Women Veterans: A Snapshot.
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West SK, Peek B, Al-Achi A, and LeCompte D
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Prior research characterizes mainly male veteran preferences at end of life using the Veterans Administration Advance Directive (VA AD), there has been no specific studies focusing on women veteran's preferences concerning whether the AD is to be strictly (S) followed or to serve as a general guide (G). The purpose of this study was to describe women veteran preferences for life-sustaining treatments (LSTs) in various illness situations to assist providers in discussing end-of-life decisions. Additionally, we compared previously published LST preferences of male veterans with the study's sample. Using a descriptive retrospective approach, data was collected from 484 women veterans ADs between January 2010 and December 2019. Findings revealed that women tended to trend in the same direction as men, preferring to have advance directives serve as general guidance over being strictly followed. Unconscious/Coma/Vegetative was the only factor that was statistically significant for affecting the choice of following the AD., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2022
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50. Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger: A Cluster Randomized Clinical Trial.
- Author
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Arzika AM, Mindo-Panusis D, Abdou A, Kadri B, Nassirou B, Maliki R, Alsoudi AF, Zhang T, Cotter SY, Lebas E, O'Brien KS, Callahan EK, Bailey RL, West SK, Goodhew EB, Martin DL, Arnold BF, Porco TC, Lietman TM, and Keenan JD
- Subjects
- Adult, Anti-Bacterial Agents, Azithromycin therapeutic use, Child, Child, Preschool, Chlamydia trachomatis, Humans, Infant, Newborn, Inflammation drug therapy, Male, Niger epidemiology, Prevalence, Seroepidemiologic Studies, Gonorrhea, Infant, Newborn, Diseases, Trachoma drug therapy, Trachoma epidemiology, Trachoma prevention & control
- Abstract
Importance: Because transmission of ocular strains of Chlamydia trachomatis is greatest among preschool-aged children, limiting azithromycin distributions to this age group may conserve resources and result in less antimicrobial resistance, which is a potential advantage in areas with hypoendemic trachoma and limited resources., Objective: To determine the efficacy of mass azithromycin distributions to preschool-aged children as a strategy for trachoma elimination in areas with hypoendemic disease., Design, Setting, and Participants: In this cluster randomized clinical trial performed from November 23, 2014, until July 31, 2017, thirty rural communities in Niger were randomized at a 1:1 ratio to biannual mass distributions of either azithromycin or placebo to children aged 1 to 59 months. Participants and study personnel were masked to treatment allocation. Data analyses for trachoma outcomes were performed from October 19, 2021, through June 10, 2022., Interventions: Every 6 months, a single dose of either oral azithromycin (20 mg/kg using height-based approximation for children who could stand or weight calculation for small children) or oral placebo was provided to all children aged 1 to 59 months., Main Outcomes and Measures: Trachoma was a prespecified outcome of the trial, assessed as the community-level prevalence of trachomatous inflammation-follicular and trachomatous inflammation-intense through masked grading of conjunctival photographs from a random sample of 40 children per community each year during the 2-year study period. A secondary outcome was the seroprevalence of antibodies to C trachomatis antigens., Results: At baseline, 4726 children in 30 communities were included; 1695 children were enrolled in 15 azithromycin communities and 3031 children were enrolled in 15 placebo communities (mean [SD] proportions of boys, 51.8% [4.7%] vs 52.0% [4.2%]; mean [SD] age, 30.8 [2.8] vs 30.6 [2.6] months). The mean coverage of study drug for the 4 treatments was 79% (95% CI, 75%-83%) in the azithromycin group and 82% (95% CI, 79%-85%) in the placebo group. The mean prevalence of trachomatous inflammation-follicular at baseline was 1.9% (95% CI, 0.5%-3.5%) in the azithromycin group and 0.9% (95% CI, 0-1.9%) in the placebo group. At 24 months, trachomatous inflammation-follicular prevalence was 0.2% (95% CI, 0-0.5%) in the azithromycin group and 0.8% (95% CI, 0.2%-1.6%) in the placebo group (incidence rate ratio adjusted for baseline: 0.18 [95% CI, 0.01-1.20]; permutation P = .07)., Conclusions and Relevance: The findings of this trial do not show that biannual mass azithromycin distributions to preschool-aged children were more effective than placebo, although the underlying prevalence of trachoma was low. The sustained absence of trachoma even in the placebo group suggests that trachoma may have been eliminated as a public health problem in this part of Niger., Trial Registration: ClinicalTrials.gov Identifier: NCT02048007.
- Published
- 2022
- Full Text
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