Infrared Thermal Imaging as a Novel Non-Invasive Point-Of-Care Tool to Assess Filarial Lymphoedema

Lymphatic filariasis causes disfiguring and disabling lymphoedema, which is commonly and frequently exacerbated by acute dermatolymphangioadenitis (ADLA). Affected people require long‐term care and monitoring but health workers lack objective assessment tools. We examine the use of an infrared thermal imaging camera as a novel non‐invasive point‐of‐care tool for filarial lower‐limb lymphoedema in 153 affected adults from a highly endemic area of Bangladesh. Tem‐perature differences by lymphoedema stage (mild, moderate, severe) and ADLA history were vis‐ualised and quantified using descriptive statistics and regression models. Temperatures were found to increase by severity and captured subclinical differences between no lymphoedema and mild lymphoedema, and differences between moderate and severe stages. Toes and ankle temperatures detected significant differences between all stages other than between mild and moderate stages. Significantly higher temperatures, best captured by heel and calf measures, were found in partici‐pants with a history of ADLA, compared to participants who never had ADLA, regardless of the lymphoedema stage. This novel tool has great potential to be used by health workers to detect sub‐clinical cases, predict progression of disease and ADLA status, and monitor pathological tissue changes and stage severity following enhanced care packages or other interventions in people af‐fected by lymphoedema

Effect of an Enhanced Self-Care Protocol on Lymphedema Status among People affected by Moderate to Severe Lower-Limb Lymphedema in Bangladesh, a Cluster Randomized Controlled Trial

Background: Lymphatic filariasis (LF) is a major cause of lymphedema, affecting over 16 million people globally. A daily, hygiene-centered self-care protocol is recommended and effective in reducing acute attacks caused by secondary infections. It may also reverse lymphedema status in early stages, but less so as lymphedema advances. Lymphatic stimulating activities such as self-massage and deep-breathing have proven beneficial for cancer-related lymphedema, but have not been tested in LF-settings. Therefore, an enhanced self-care protocol was trialed among people affected by moderate to severe LF-related lymphedema in northern Bangladesh. Methods: Cluster randomization was used to allocate participants to either standard- or enhanced-self-care groups. Lymphedema status was determined by lymphedema stage, mid-calf circumference, and mid-calf tissue compressibility. Results: There were 71 patients in each group and at 24 weeks, both groups had experienced significant improvement in lymphedema status and reduction in acute attacks. There was a significant and clinically relevant between-group difference in mid-calf tissue compressibility with the biggest change observed on legs affected by severe lymphedema in the enhanced self-care group (∆ 21.5%, −0.68 (−0.91, −0.45), p < 0.001). Conclusion: This study offers the first evidence for including lymphatic stimulating activities in recommended self-care for people affected by moderate and severe LF-related lymphedem

Insights on Lymphedema Self-Care Knowledge and Practice in Filariasis and Podoconiosis-Endemic Communities in Bangladesh and Ethiopia

Lymphedema is a life-long sequelae to several neglected tropical diseases (NTD). In Bangladesh the main cause is lymphatic filariasis (LF) and Ethiopia is endemic for both LF and podoconiosis. The World Health Organization (WHO) recommends daily self-care including meticulous washing and drying of affected skin and attention to entry lesions, limb exercises and elevation. Adherence to this regime reduces secondary infections which cause disabling episodes of acute dermato-lymphangitis (ADL). Self-care practices must be integrated into family life, supported by community and monitored by health staff; however, little is known about the influence of personal and socio-demographic factors on adherence. People affected by lymphedema (n=272), adult caregivers (n=272), and health workers (n=68) in Bangladesh and Ethiopia were trained in lymphedema management according to WHO recommendations. Surveys on the causes and management of lymphedema were collected at baseline and 24-weeks, and patients completed a daily journal of self-care activities and symptoms. At baseline knowledge on causes and management of lymphedema was greater among health workers (&amp;gt;70%) than patients and caregivers (&amp;lt;20%) in both countries, and there were significant between-country differences in patient reported use of limb washing (Bangladesh = 7.7%. Ethiopia = 51.1%, p = 0.001). At 24-weeks knowledge on lymphedema causes and management had increased significantly among patients and caregivers, there was &amp;lt;70% adherence to limb washing and exercises, but lesser use of limb elevation in both countries. A range of patient characteristics were associated with significant variation in self-care, except for limb washing. Performance of fewer leg exercises was significantly associated with increased age or severe lymphedema in Bangladesh, and with being female or in paid work in Ethiopia. Patient journals recorded ADL symptoms and working days lost due to lymphedema more frequently than were reported by recall during the 24-week survey. Core elements of lymphedema self-care education, training and monitoring are the same for multiple etiologies. This creates opportunities for cross-cutting implementation of integrated service delivery across several skin NTDs. Sustainability will depend on community level ownership and research on factors affecting adherence to lymphedema self-care are urgently needed.</jats:p

Intra-Rater Reliability and Agreement of the Indurometer When Used to Assess Mid-Calf Tissue Compressibility Among People Affected by Moderate to Severe Lymphedema in Bangladesh and Ethiopia

Background: Lymphedema is a chronic skin disease that induces tissue fibrosis (stiffness). Tissue tonometry has been used to assess skin and tissue compressibility in lymphedema, primarily in research on arm lymphedema after breast cancer. A digital tonometer, the Indurometer (Flinders and SA Biomedical Engineering, Australia), has shown excellent intra-rater reliability in young healthy people in Australia and Myanmar and was able to detect covert changes in young, asymptomatic Myanmar people infected with lymphatic filariasis. It has not been tested in overt lower-limb lymphedema. Methods and Results: The Indurometer was used in a cluster randomized trial in Bangladesh and Ethiopia to measure tissue compressibility among adults affected by moderate to severe lymphatic filariasis- or podoconiosis-related leg lymphedema. The study compared different self-care intervention and after baseline there were follow-ups at 4, 12, and 24 weeks. Three consecutive Indurometer scores were collected by two data collection teams in each country at the mid-calf of each leg. Indurometer scores were available for three timepoints in Bangladesh and four time-points in Ethiopia. An intra-class correlation coefficient (ICC) was calculated for each data collection team, and a coefficient of variation (CV) was used to assess measurement agreement in moderate and severe stages of lymphedema. The intra-rater reliability among local research assistants was good to excellent in both countries at all time-points (ICC range 0.829 [95% confidence interval; CI 0.730–0.896]-0.992 [95% CI 0.989–0.995]). In Bangladesh, agreement between measures was highest among unaffected legs (range 16%–22%) and lowest in severe lymphedema (range 19%–39%). CV scores in Ethiopia showed no distinct pattern for lymphedema stage (range 15%–32%). Conclusion: The Indurometer is an inexpensive and easy-to-use device to assess skin and tissue compressibility and should be considered in clinical research on lower-limb lymphedema

Socio-economic and environmental factors associated with high lymphatic filariasis morbidity prevalence distribution in Bangladesh

Background Lymphatic filariasis (LF) is a vector-borne parasitic disease which affects 70 million people worldwide and causes life-long disabilities. In Bangladesh, there are an estimated 44,000 people suffering from clinical conditions such as lymphoedema and hydrocoele, with the greatest burden in the northern Rangpur division. To better understand the factors associated with this distribution, this study examined socio-economic and environmental factors at division, district, and sub-district levels. Methodology A retrospective ecological study was conducted using key socio-economic (nutrition, poverty, employment, education, house infrastructure) and environmental (temperature, precipitation, elevation, waterway) factors. Characteristics at division level were summarised. Bivariate analysis using Spearman’s rank correlation coefficient was conducted at district and sub-district levels, and negative binomial regression analyses were conducted across high endemic sub-districts (n = 132). Maps were produced of high endemic sub-districts to visually illustrate the socio-economic and environmental factors found to be significant. Results The highest proportion of rural population (86.8%), poverty (42.0%), tube well water (85.4%), and primary employment in agriculture (67.7%) was found in Rangpur division. Spearman’s rank correlation coefficient at district and sub-district level show that LF morbidity prevalence was significantly (p&lt;0.05) positively correlated with households without electricity (district rs = 0.818; sub-district rs = 0.559), households with tube well water (sub-district rs = 0.291), households without toilet (district rs = 0.504; sub-district rs = 0.40), mean annual precipitation (district rs = 0.695; sub-district rs = 0.503), mean precipitation of wettest quarter (district rs = 0.707; sub-district rs = 0.528), and significantly negatively correlated with severely stunted children (district rs = -0.723; sub-district rs = -0.370), mean annual temperature (district rs = -0.633.; sub-district rs = 0.353) and mean temperature (wettest quarter) ((district rs = -0.598; sub-district rs = 0.316) Negative binomial regression analyses at sub-district level found severely stunted children (p = &lt;0.001), rural population (p = 0.002), poverty headcount (p = 0.001), primary employment in agriculture (p = 0.018), households without toilet (p = &lt;0.001), households without electricity (p = 0.002) and mean temperature (wettest quarter) (p = 0.045) to be significant. Conclusions This study highlights the value of using available data to identify key drivers associated with high LF morbidity prevalence, which may help national LF programmes better identify populations at risk and implement timely and targeted public health messages and intervention strategies. </jats:sec

Developing the first national database and map of lymphatic filariasis clinical cases in Bangladesh: Another step closer to the elimination goals

BackgroundThe Bangladesh Lymphatic Filariasis (LF) Elimination Programme has made significant progress in interrupting transmission through mass drug administration (MDA) and has now focussed its efforts on scaling up managing morbidity and preventing disability (MMDP) activities to deliver the minimum package of care to people affected by LF clinical conditions. This paper highlights the Bangladesh LF Programme's success in conducting a large-scale cross-sectional survey to determine the number of people affected by lymphoedema and hydrocoele, which enabled clinical risk maps to be developed for targeted interventions across the 34 endemic districts (19 high endemic; 15 low endemic).Methodology/principal findingsIn the 19 high endemic districts, 8,145 community clinic staff were trained to identify and report patients in their catchment area. In the 15 low endemic districts, a team of 10 trained field assistants conducted active case finding with cases reported via a SMS mHealth tool. Disease burden and prevalence maps were developed, with morbidity hotspots identified at sub-district level based on a combination of the highest prevalence rates per 100,000 and case-density rates per square kilometre (km2). The relationship between morbidity and baseline microfilaria (mf) prevalence was also examined. In total 43,678 cases were identified in the 19 high endemic districts; 30,616 limb lymphoedema (70.1%; female 55.3%), 12,824 hydrocoele (29.4%), and 238 breast/female genital swelling (0.5%). Rangpur Division reported the highest cases numbers and prevalence of lymphoedema (26,781 cases, 195 per 100,000) and hydrocoele (11661 cases, 169.6 per 100,000), with lymphoedema predominately affecting females (n = 21,652). Rangpur and Lalmonirhat Districts reported the highest case numbers (n = 11,199), and prevalence (569 per 100,000) respectively, with five overlapping lymphoedema and hydrocoele sub-district hotspots. In the 15 low endemic districts, 732 cases were identified; 661 lymphoedema (90.2%; female 39.6%), 56 hydrocoele (7.8%), and 15 both conditions (2.0%). Spearman's correlation analysis found morbidity and mf prevalence significantly positively correlated (r = 0.904; pConclusions/significanceThe Bangladesh LF Programme has developed one of the largest, most comprehensive country databases on LF clinical conditions in the world. It provides an essential database for health workers to identify local morbidity hotspots, deliver the minimum package of care, and address the dossier elimination requirements

The significant scale up and success of Transmission Assessment Surveys 'TAS' for endgame surveillance of lymphatic filariasis in Bangladesh: One step closer to the elimination goal of 2020

Background Bangladesh had one of the highest burdens of lymphatic filariasis (LF) at the start of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) with an estimated 70 million people at risk of infection across 34 districts. In total 19 districts required mass drug administration (MDA) to interrupt transmission, and 15 districts were considered low endemic. Since 2001, the National LF Programme has implemented MDA, reduced prevalence, and been able to scale up the WHO standard Transmission Assessment Survey (TAS) across all endemic districts as part of its endgame surveillance strategy. This paper presents TAS results, highlighting the momentous geographical reduction in risk of LF and its contribution to the global elimination target of 2020. Methodology/Principal findings The TAS assessed primary school children for the presence of LF antigenaemia in each district (known as an evaluation unit—EU), using a defined critical cut-off threshold (or ‘pass’) that indicates interruption of transmission. Since 2011, a total of 59 TAS have been conducted in 26 EUs across the 19 endemic MDA districts (99,148 students tested from 1,801 schools), and 22 TAS in the 15 low endemic non-MDA districts (36,932 students tested from 663 schools). All endemic MDA districts passed TAS, except in Rangpur which required two further rounds of MDA. In total 112 students (male n = 59; female n = 53), predominately from the northern region of the country were found to be antigenaemia positive, indicating a recent or current infection. However, the distribution was geographically sparse, with only two small focal areas showing potential evidence of persistent transmission. Conclusions/Significance This is the largest scale up of TAS surveillance activities reported in any of the 73 LF endemic countries in the world. Bangladesh is now considered to have very low or no risk of LF infection after 15 years of programmatic activities, and is on track to meet elimination targets. However, it will be essential that the LF Programme continues to develop and maintain a comprehensive surveillance strategy that is integrated into the health infrastructure and ongoing programmes to ensure cost-effectiveness and sustainability

Summary of LF morbidity prevalence, socio-economic and environmental factors by division.

Summary of LF morbidity prevalence, socio-economic and environmental factors by division.</p

The development and roll-out of a new hydrocoele surgery facility assessment tool for the elimination of lymphatic filariasis

Abstract A hydrocoele surgery facility assessment tool (HSFAT) was developed to assess the readiness of hydrocoele surgery services in health facilities prior to implementation of hydrocoele surgical campaigns for the elimination of lymphatic filariasis (LF). A first version of the tool was piloted in Bangladesh, Malawi and Nepal in 2019, then, following feedback from country programme managers, a second version of the tool was rolled out across countries implementing hydrocoele surgery in the Accelerating the Control of Neglected Tropical Diseases (Ascend) West and Central Africa Programme, including Benin, Burkina Faso, Ghana, Guinea, Niger and Nigeria. The HSFAT assessed facilities across 10 domains: background information, essential amenities, emergency patient transfer, laboratory capacity, surgical procedures and trained staff, infection prevention, non-disposable basic equipment, disposable basic equipment, essential medicines and current hydrocoele practices. The HSFAT results highlight key areas for improvement in different countries and can be used to develop a quality improvement plan, which may include actions with agreed deadlines to improve the readiness and quality of hydrocoele surgery services provided by the health facility, prior to implementation of surgical campaigns and assist country programmes to achieve the dossier requirements set out by the World Health Organization for the elimination of LF.</jats:p