Use of an inexpensive magnifier with light source in the diagnosis of trichiasis among community-based case finders in Nigeria

Optimizing Trichiasis Case Finding to Attain the Elimination of Trachoma as a Public Health Problem

BACKGROUND

As national trachoma programmes increase efforts to reduce the burden of trachomatous trichiasis (TT), TT case finding and referral are critical public health programme components. Our research aimed to explore the most effective and efficient approaches to finding, referring, and managing TT cases.

METHODS

This was a prospective descriptive study, utilizing both routine programme data and primary data collection. This study compared four different approaches to finding TT cases across three different local government areas (LGAs) in Kano State, Nigeria. Each of the study LGAs was divided into four sub-units to accommodate the four different approaches.

RESULTS

The number of outreach attendees was 4795 across the four case finding approaches, and this varied hugely, with the smallest number and proportion (403, 0.26%) in settings only employing house-to-house case finding and the largest number and proportion (1901, 0.99%) when town criers were used. That said, the proportion of TT cases among people presenting at outreach was highest (32.5%) when house-to-house case finding was used and lowest (10.3%) when town criers were used. More female TT patients were found (53-70%) and had surgery (79-85%) compared to male cases, across all approaches. The average project expenditure for finding one TT case was similar for approaches that included house-to-house case finding (USD 5.4-6.3), while it was 3.5 times higher (USD 21.5 per TT case found) when town criers were used.

DISCUSSION

This study found that the house-to-house TT case finding approaches were the most efficient method with the highest yield of TT cases. Including other eye condition and/or vision testing yielded similar results but required more personnel and cost.

Progress towards the elimination of trachoma in Nigeria

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

Effectiveness of Trachomatous Trichiasis Case-identification Approaches in Ethiopia

BACKGROUND

Trachoma control programs use multiple approaches to identify individuals with trachomatous trichiasis (TT). Evidence is limited regarding which approaches are most effective and cost-efficient.

METHODS

We evaluated the effectiveness of two TT case-identification approaches in Ethiopia: community mobilization to encourage self-referral for centralized screening and house-to-house screenings conducted by case finders. We compared the number of true cases found per 1000 population and costs associated with case identification under each approach, stratified by villages that received one or multiple screening visits.

RESULTS

We conducted screenings in 396 villages. In villages receiving one house-to-house visit, case finders identified 14,229 suspected cases, of whom 10,513 (73.9%) presented for TT confirmation. A median of 17.2% (interquartile range [IQR]: 9.1%-27.8%) of those presenting truly had TT (positive predictive value). In single-visit villages, the community mobilization approach yielded higher rates of confirmed cases than the house-to-house approach (1.5 [IQR: 1.1, 2.6] vs. 1.1 [IQR: 0.5, 1.9] cases per 1000 population), and the median cost of identifying a TT case was less ($5.59 vs. $31.18) using community mobilization than house-to-house. In multiple-visit villages, additional screening visits increased the median rate of confirmed cases to 2.5 per 1000 population in community mobilization villages, but the rate remained unchanged in house-to-house villages.

CONCLUSIONS

Community mobilization-based TT case finding had a higher yield than house-to-house, at a substantially lower cost. Future research should examine whether additional tools to aid case finders in their diagnosis increases case-finding efficiency and accuracy and whether TT prevalence and surgical program duration impact case-finding success.

Trachoma

Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectious-inflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individual's lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse.

Piloting a trachomatous trichiasis patient case-searching approach in two localities of Sudan

Background

Approximately 1.9 million people have become blind or visually impaired from trachoma, the leading cause of infectious blindness. Trachoma prevalence surveys conducted in Sudan have shown that thousands of Sudanese suffer from the advanced stages of the disease, trachomatous trichiasis (TT), and warrant sight-saving surgery. Sudan’s National Trachoma Control Program (NTCP) provides free TT surgery; however, given that many TT patients live in remote areas with limited access to health services, identifying patients and providing eye care services has proved challenging. For this reason, the Sudan NTCP piloted a systematic TT case-finding approach to identify patients.

Methods

In Gedarif state, 11 villages in Baladyat el Gedarif locality and 21 villages in West Galabat locality were included in a TT case-searching activity from September to November 2018. TT case finders were selected from the villages where the activity took place and were trained by ophthalmic medical assistants to identify possible patients.

Results

Of 66 626 villagers examined, 491 were identified as having TT by TT case finders. Of those, 369 were confirmed as true cases by the TT surgeons, a 75.2% (369/491) success rate.

Conclusions

The TT case-finding approach provides an example of an effective method for identifying TT patients and should be expanded to other parts of the country known to be endemic for trachoma.