Gender equity and trichiasis surgery in the Vietnam and Tanzania national trachoma control programmes

Gender differences in the surgical management of trachomatous trichiasis: an exploratory analysis of global trachoma survey data, 2015-2019

BACKGROUND

Trachomatous trichiasis (TT) is a painful, potentially blinding eye condition that can be managed through epilation or surgery. Women are affected by TT approximately twice as often as men and are believed to face gendered barriers to receiving surgical care to prevent vision loss.

METHODS

We used data from 817 cross-sectional surveys conducted during 2015-2019 in 20 African countries to estimate the prevalence difference (PD) between female and male eyes for four outcomes potentially indicating gender-related differences in TT management: (1) received surgery and developed postoperative TT (PTT), (2) never offered surgery, (3) offered surgery but declined it, and (4) offered epilation but never offered surgery.

RESULTS

The prevalence was modestly elevated among female eyes compared with male eyes for having PTT (PD:1.8 [95% confidence limits (CL): 0.6, 3.0]) and having declined surgery for the eye (PD: 6.2 [95% CL: 1.8, 10.7]). The proportion offered epilation was similar by gender (PD:0.5 [95% CL: -0.4, 1.3]), while never having been offered surgery was somewhat more prevalent among male eyes (PD: -2.1 [95% CL: -3.5, -0.7]).

CONCLUSIONS

Our results suggest potential gender differences in TT management. More research is needed to determine the causes and implications of the observed differences.

Global trends in blindness and vision impairment due to corneal opacity 1984-2020: a meta-analysis

TOPIC

We provide global estimates of the prevalence of corneal blindness and vision impairment in adults 40 years and older and examine the burden by age, gender, and geographic region from 1984-2020.

CLINICAL RELEVANCE

Corneal opacities (CO) are among the top five causes of blindness worldwide, yet the global prevalence, regional differences, and risk factors are unclear.

METHODS

Abstracted data from the published literature and surveys were obtained from the Global Burden of Disease Vision Loss Expert Group. We supplemented this by an independent systematic literature search of PubMed, Embase, Web of Science, Scopus, and Cochrane. Studies that provided CO vision impairment data based on population-based surveys for subjects 40 years of age or older were included, for a total of 244. For each of the four outcomes of blindness and moderate to severe vision impairment (MSVI) caused by trachomatous and non-trachomatous CO (NTCO), time trends and differences in prevalence by region, age, and sex were evaluated using a Poisson log-linear model with a generalized estimating equation method. Age-standardized estimates of global prevalence of blindness and MSVI were calculated using the 2015 United Nations standard populations.

RESULTS

The global prevalence of blindness due to NTCO in those 40 years and older was 0.081% (95% CI=0.049% to 0.315%); MSVI was 0.130% (95% CI= 0.087% to 0.372%). There was a significant increase with age (prevalence rate ratio=2.15, 95% CI=1.99-2.32). Latin America and Europe had the lowest rates, with 2-8 fold higher rates of blindness/MSVI in the other regions. The global prevalence of blindness due to trachomatous CO in those 50 years and older was 0.013% (95% CI=0.006% to 0.043%); MSVI was 0.180% (95% CI=0.006% to 0.049%). Trachomatous CO blindness and MSVI increased with age and female gender, and rates were significantly higher in the African regions; a decrease in blindness rates over time was found (prevalence rate ratio estimate=0.91, 95% CI=0.86-0.96).

CONCLUSION

An estimated 5.5 million persons worldwide are bilaterally blind or with MSVI due to CO, with an additional 6.2 million unilaterally blind. Trachomatous CO blindness is declining over time, likely due to the massive scaleup of the global trachoma elimination program and overall socioeconomic development.

Prevalence of trachoma in the Republic of Chad: results of 41 population-based surveys

PURPOSE

To estimate the prevalence of trachoma in suspected-endemic areas of Chad, and thereby determine whether trachoma is a public health problem requiring intervention.

METHODS

We divided the suspected-endemic population living in secure districts into 46 evaluation units (EUs), and used the standardized methodologies of the Global Trachoma Mapping Project. A two-stage cluster-sampling procedure was adopted. In each EU, the goal was to examine at least 1019 children aged 1-9 years by recruiting 649 households; all consenting residents aged ≥ 1 year living in those households were examined. Each participant was examined for trachomatous inflammation-follicular (TF), trachomatous inflammation-intense (TI), and trichiasis.

RESULTS

Two EUs had data that could not be validated, and were excluded from the analysis. GPS data for three other pairs of EUs suggested that EU divisions were inaccurate; data for each pair were combined within the pair. In the 41 resulting EUs, 29,924 households in 967 clusters were visited, and 104,584 people were examined. The age-adjusted EU-level prevalence of TF in 1-9-year-olds ranged from 0.0% to 23.3%, and the age- and gender-adjusted EU-level prevalence of trichiasis in ≥ 15-year-olds ranged from 0.02% to 1.3%. TF was above the WHO elimination threshold in 16 EUs (39%) and trichiasis was above the WHO elimination threshold in 29 EUs (71%). Women had a higher prevalence of trichiasis than did men in 31 EUs (76%). A higher ratio of trichiasis prevalence in women to trichiasis prevalence in men was associated (p = 0.03) with a higher prevalence of trichiasis at EU level.

CONCLUSION

Public health-level interventions against trachoma are needed in Chad. Over 10,000 people need management of their trichiasis; women account for about two-thirds of this total. The association between a higher ratio of trichiasis prevalence in women to that in men with higher overall trichiasis prevalence needs further investigation.

Prevalence of trachoma in the Kayes region of Mali eight years after stopping mass drug administration

BACKGROUND

In 2009, three years after stopping mass treatment with azithromycin, a trachoma impact survey in four health districts in the Kayes region of Mali found a prevalence of trachomatous inflammation-follicular (TF) among children aged 1 to 9 years of >5% and a trachomatous trichiasis (TT) prevalence within the general population (≥1-year-old) of <1%. As a result, the government's national trachoma program expanded trichiasis surgery and related activities required to achieve trachoma elimination.

METHODOLOGY/PRINCIPAL FINDINGS

In 2015, to assess progress towards elimination, a follow-up impact survey was conducted in the Kayes, Kéniéba, Nioro and Yélimané health districts. The survey used district level two-stage cluster random sampling methodology with 20 clusters of 30 households in each evaluation unit. Subjects were eligible for examination if they were ≥1 year. TF and TT cases were identified and confirmed by experienced ophthalmologists. In total 14,159 people were enumerated and 11,620 (82%) were examined. TF prevalence (95% confidence interval (CI)) was 0.5% (0.3-1%) in Kayes, 0.8% (0.4-1.7%) in Kéniéba, 0.2% (0-0.9%) in Nioro and 0.3% (0.1-1%) in Yélimané. TT prevalence (95% CI) was 0.04% (0-0.25%) in Kayes, 0.29% (0.11-0.6%) in Kéniéba, 0.04% (0-0.25%) in Nioro and 0.07% (0-0.27%) in Yélimané.

CONCLUSIONS/SIGNIFICANCE

Eight years after stopping MDA and intensifying trichiasis surgery outreach campaigns, all four districts reached the TF elimination threshold of <5% and three of four districts reached the TT elimination threshold of <0.1%.

Prevalence and Risk Factors for Trachoma in Rural Areas of Sistan-va-Baluchestan Province, Iran: A Population-Based Study

PURPOSE

To determine the prevalence of trachoma and risk factors associated with the disease in rural areas of the Sistan-va-Baluchestan province in Iran from 2012-2013. Population-based prevalence data for trachoma is lacking in this region.

METHODS

In this population-based cross-sectional study, 80 clusters were selected using a systematic and probability proportional to size method. All participants underwent clinical eye examinations according to the World Health Organization simplified trachoma grading system. The prevalence of follicular trachoma (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in women aged over 15 years were the most important clinical indicators of trachoma.

RESULTS

The study surveyed 8187 individuals and analyzed 7912 participants (96.6%) including 3737 children aged 1-9 years and 4175 females >15 years. The prevalence of TF and TT in the relevant indicator groups were 0.59% (95% confidence interval, CI, 0.36-0.89%) and 0.02% (95% CI 0.00-0.13%), respectively.

CONCLUSION

Previously, trachoma prevalence data for this region were lacking. This study confirms that the Sistan-va-Baluchestan region is not endemic for trachoma. This has important implications for national trachoma elimination activities.

Prevalence of trachoma in the north region of Cameroon: results of a survey in 15 health districts

Background

To estimate the prevalence of trachoma in the North Region of Cameroon in order to facilitate the planning of trachoma control activities in this region, a survey was carried out in 2011 and 2012 in 15 health districts (HDs).

Methodology

A cross-sectional, two-stage cluster random sampling survey was carried out. The survey focused on two target populations: children aged 1 to 9 years for the prevalence of Trachomatous Inflammation-Follicular (TF) and those aged 15 and over for the prevalence of Trachomatous Trichiasis (TT). The sample frame was an exhaustive list of villages and neighborhoods of HDs. The World Health Organization simplified trachoma grading system was used for the recognition and registration of cases of trachoma.

Principal Findings

30,562 children aged 1 to 9 years and 24,864 people aged 15 and above were examined. In children aged 1–9 years, the overall prevalence of TF was 4.2% (95% confidence intervals (CI): 4.0–4.5%). Three (3) of 15 HDs in the region showed TF prevalence of ≥10% (Poli, Rey Bouba, and Tcholliré). The overall TT prevalence was 0.25% (95% CI: 0.20–0.33%). There were estimated 1265 TT cases in the region. The prevalence of blindness was 0.01% (95% CI: 0.00–0.03%), low vision was 0.11% (95% CI: 0.07–0.17%), and corneal opacity was 0.22% (95% CI: 0.17–0.29%).

Conclusions/Significance

This survey provides baseline data for the planning of activities to control trachoma in the region. The overall prevalence of TF in the region is 4.2%, and that of TT is 0.2%; three HDs have a TF prevalence ≥10%. These three HDs are eligible for mass drug administration with azythromycin, along with the implementation of the “F” and “E” components of the SAFE strategy.

Trachoma is the most common infectious cause of blindness. Recurrent episodes of infection with Chlamydia trachomatis cause conjunctival inflammation in children who go on to develop scarring and blindness as adults. The current effort led by the World Health Organization (WHO) and the Alliance for Global Elimination of Blinding Trachoma by the year 2020 (GET2020) is to eliminate trachoma as a blinding disease worldwide by the year 2020 using the SAFE strategy (Surgery, Antibiotics, Facial cleanliness and Environmental improvement). To estimate the prevalence of trachoma in the North Region of Cameroon in order to facilitate the planning of trachoma control activities in this region, a survey was carried out in 2011 and 2012 in 15 health districts (HDs). The overall prevalence of TF in the region is 4.2%, and that of TT is 0.25%; three HDs have a TF prevalence ≥10%. These three HDs are eligible for mass drug administration with azythromycin, along with the implementation of the “F” and “E” components of the SAFE strategy. There were estimated 1265 TT. This survey provides baseline data for the planning of activities to control trachoma in the region.

Prevalence of trachoma in the Far North region of Cameroon: results of a survey in 27 Health Districts

Background

Cameroon is known to be endemic with trachoma. To appreciate the burden of the disease and facilitate the national planning of trachoma control in the integrated control program for the neglected tropical diseases, an epidemiological mapping of trachoma was conducted in the Far North region in 2010–11.

Methodology

A cross-sectional, cluster random sampling survey was carried out. The survey focused on two target populations: children aged 1 to 9 years for the prevalence of active trachoma and those aged 15 and over for the prevalence of trichiasis (TT). The sample frame was an exhaustive list of villages and neighborhoods of Health Districts (HDs). The World Health Organization simplified trachoma grading system was used for the recognition and registration of cases of trachoma.

Principal Findings

48,844 children aged 1 to 9 years and 41,533 people aged 15 and over were examined. In children aged 1–9 years, the overall prevalence of trachomatous inflammation–follicular (TF) was 11.2% (95% confidence intervals (CI): 11.0–11.5%). More girls were affected than boys (p = 0.003). Thirteen (13) of 27 HDs in the region showed TF prevalence of ≥10%. The overall TT prevalence was 1.0% (95% CI: 0.9–1.1%). There were estimated 17193 (95% CI: 12576–25860) TT cases in the region. The prevalence of blindness was 0.04% (95% CI: 0.03–0.07%) and visual impairment was 0.09% (95% CI: 0.07–0.13%).

Conclusions/Significance

The survey confirmed that trachoma is a public health problem in the Far North region with 13 HDs qualified for district-level mass drug administration with azithromycin. It provided a foundation for the national program to plan and implement the SAFE strategy in the region. Effort must be made to find resources to provide the surgical operations to the 17193 TT cases and prevent them from becoming blind.

Trachoma is the leading infectious cause of blindness in the world, which is caused by repeated eye infections with the bacterium Chlamydia trachomatis. The global objective of trachoma control is to eliminate trachoma as a blinding disease worldwide by Year 2020, using the World Health Organization-endorsed SAFE strategy (Surgery to correct trichiasis, Antibiotics to treat infection, Facial cleanliness and Environmental improvement to interrupt transmission). In order to implement the control program, the knowledge of the disease distribution and prevalence in each district is essential. Disease mapping surveys were conducted in 27 health districts in the Far North region in Cameroon. Thirteen health districts have a prevalence of trachomatous inflammation–follicular ≥10% in children aged 1–9 years and qualify for district-level mass antibiotic treatment as well as intensive implementation of other components of SAFE. There are estimated to be 17193 trichiasis cases in the region, which need surgical operations to prevent from being blinded. The survey provided a foundation for the national program to plan and implement the SAFE strategy in the region.

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

Background

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

Methods

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

Results

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

Conclusion

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

Prevalence of and risk factors for trachoma in Kano state, Nigeria

Background

In northern Nigeria, trachoma is an important public health problem, but there are currently few population-based data on prevalence of disease and no formal trachoma control programs.

Methodology / Principal Findings

In Kano state, Nigeria, we conducted a population-based cross-sectional survey using multistage cluster random sampling, combining examination for clinical signs of trachoma and application of questionnaires assessing potential household-level risk factors. A total of 4491 people were examined in 40 clusters, of whom 1572 were aged 1–9 years, and 2407 (53.6%) were female. In 1–9 year-olds, the prevalence of trachomatous inflammation–follicular (TF) was 17.5% (95% CI: 15.7–19.5%). In a multivariate model, independent risk factors for active trachoma were the presence of flies on the face (OR 1.98, 95% CI 1.30–3.02); a dirty face (OR 2.45, 95% CI 1.85–3.25) and presence of animal dung within the compound of residence (OR 3.46, 95% CI 1.62–7.41). The prevalence of trachomatous trichiasis in persons aged ≥15years was 10.9% (95% CI: 9.7–12.2%). Trichiasis was significantly more common in adult females than in adult males.

Conclusion/Significance

There is an urgent need for a trachoma control program in Kano state, with emphasis given to provision of good quality trichiasis surgery. Particular effort will need to be made to identify women with trichiasis and engage them with appropriate services while also taking steps to secure azithromycin for mass treatment and ensuring personal and environmental hygiene.

Overcoming gender inequity in prevention of blindness and visual impairment in Africa

Background:

Globally, and in Africa, after adjusting for age, women are about 1.4 times more likely to be blind than men. While women generally live longer than men, the lack of accessibility to and use of services is likely the most important reason for excess blindness in women in Africa.

Aim:

We sought to review the literature on vision loss in Africa and summarize the findings related to gender equity.

Materials and Methods:

Information from across sub-Saharan Africa was collected on the evidence of gender inequity and reasons for this inequity. Finally, the results were used to generate suggestions on how gender equity could be improved.

Results:

In all published surveys (except one), cataract surgical coverage among women was lower than cataract surgical coverage among men. Although data available are limited, similar findings appeared in the use of services for other disease conditions, notably, childhood cataract and glaucoma. Evidence suggests that a variety of approaches are needed to improve the use of eye care services. Three main strategies are needed to address gender inequity in vision loss in Africa. First, it is important to address transport needs. Second, counseling of patients and family members is required. Finally, programs need to put in place pricing systems that make the services affordable the population.

Conclusions:

VISION 2020 can be achieved in Africa, but investment is needed in a variety of strategies that will ensure that eye care services are affordable, accessible, and acceptable to women and girls.

Neglected tropical diseases in sub-saharan Africa: review of their prevalence, distribution, and disease burden

The neglected tropical diseases (NTDs) are the most common conditions affecting the poorest 500 million people living in sub-Saharan Africa (SSA), and together produce a burden of disease that may be equivalent to up to one-half of SSA's malaria disease burden and more than double that caused by tuberculosis. Approximately 85% of the NTD disease burden results from helminth infections. Hookworm infection occurs in almost half of SSA's poorest people, including 40-50 million school-aged children and 7 million pregnant women in whom it is a leading cause of anemia. Schistosomiasis is the second most prevalent NTD after hookworm (192 million cases), accounting for 93% of the world's number of cases and possibly associated with increased horizontal transmission of HIV/AIDS. Lymphatic filariasis (46-51 million cases) and onchocerciasis (37 million cases) are also widespread in SSA, each disease representing a significant cause of disability and reduction in the region's agricultural productivity. There is a dearth of information on Africa's non-helminth NTDs. The protozoan infections, human African trypanosomiasis and visceral leishmaniasis, affect almost 100,000 people, primarily in areas of conflict in SSA where they cause high mortality, and where trachoma is the most prevalent bacterial NTD (30 million cases). However, there are little or no data on some very important protozoan infections, e.g., amebiasis and toxoplasmosis; bacterial infections, e.g., typhoid fever and non-typhoidal salmonellosis, the tick-borne bacterial zoonoses, and non-tuberculosis mycobaterial infections; and arboviral infections. Thus, the overall burden of Africa's NTDs may be severely underestimated. A full assessment is an important step for disease control priorities, particularly in Nigeria and the Democratic Republic of Congo, where the greatest number of NTDs may occur.

Uptake of trichiasis surgical services in Tanzania through two village-based approaches

AIM

To determine the effectiveness of village-based strategies (using school teachers and village leaders) to increase the use of surgical services.

METHODS

A cohort study was conducted in Tanzania using two village strategies (village leader and school teachers); trichiasis surgical uptake and the factors associated with uptake were measured after 1 year.

RESULTS

The trichiasis surgical coverage at baseline was 16.9%; 200 patients who needed surgery were identified. One year later, we were able to re-examine and interview 163 of these patients. The surgical uptake among these patients was 44.8% (95% CI 37.2% to 52.4%). Patients in the school-teacher programme had a 36.5% uptake compared with 52.1% for those in the village-leader programme. No difference was observed in uptake by age or sex. Uptake was highest among those coming from multiple-generation households and those with more household wealth. Of the 90 people who still had not had surgery, 20 (22.2%) reported seeking surgery, but failing to receive it because of barriers at the provider side.

CONCLUSIONS

Improved surgical uptake for trachomatous trichiasis was achieved by using village-based promotion efforts and surgical services at existing health clinics. Even with free surgery at health clinics, indirect costs and social support barriers limit utilisation by the most vulnerable, the poorest and those living in single-generation households. Problems at the provider level also create barriers for patients who need surgery.

Contribution of sex-linked biology and gender roles to disparities with trachoma

Globally, trachoma is the leading infectious cause of blindness. Survey data consistently show that trachoma-related blindness is two to four times higher in women than men. Tracing the increased risk for trachoma and its consequences for women suggests that other factors besides biology may contribute. Understanding the reasons for the excess risk for and consequences of trachoma in girls and women requires examining a number of issues: Are girls and women more biologically susceptible to the consequences of infection with Chlamydia trachomatis? Could other factors help explain the excess of conjunctival scarring and trichiasis in women? Do gender roles affect the risk for trachoma and its consequences? Are women more likely to have recurrence after trichiasis surgery compared to men? This article explores the answers to these questions.

Trachoma: new assault on an ancient disease

Trachoma is the leading infectious cause of blindness worldwide. The World Health Organization (WHO) estimated that approximately 5.9 million persons are blind or have severe vision-loss as a result of trachoma, and another 10 million are at high risk. Trachoma preferentially affects the most deprived communities, and within these communities, women and children bear the brunt of the burden. In recent years, there has been a renewed focus on research and heightened enthusiasm for strengthening trachoma control programs in afflicted countries. WHO has convened an alliance of member countries, non-governmental organizations, and other partners for the Global Elimination of Blinding Trachoma by the year 2020, and endorsed the multi-faceted SAFE strategy for trachoma control. SAFE-Surgery, Antibiotics, Face-washing, and Environmental improvement-has incorporated sound research on elements likely to reduce trachoma, and trachomatis blindness, in endemic communities. This review summarizes current knowledge about trachoma and its causative agent, Chlamydia trachomatis, the epidemiology and risk factors for trachoma as a prelude to reviewing the SAFE strategy. While ongoing research to support the knowledge base for SAFE must continue to be a priority, the full implementation of SAFE is the best hope for countries to reduce the global burden of blindness from this preventable cause.