Persons ‘never treated’ in mass drug administration for lymphatic filariasis: identifying programmatic and research needs from a series of research review meetings 2020–2021

As neglected tropical disease programs rely on participation in rounds of mass drug administration (MDA), there is concern that individuals who have never been treated could contribute to ongoing transmission, posing a barrier to elimination. Previous research has suggested that the size and characteristics of the never-treated population may be important but have not been sufficiently explored. To address this critical knowledge gap, four meetings were held from December 2020 to May 2021 to compile expert knowledge on never treatment in lymphatic filariasis (LF) MDA programs. The meetings explored four questions: the number and proportion of people never treated, their sociodemographic characteristics, their infection status and the reasons why they were not treated. Meeting discussions noted key issues requiring further exploration, including how to standardize measurement of the never treated, adapt and use existing tools to capture never-treated data and ensure representation of never-treated people in data collection. Recognizing that patterns of never treatment are situation specific, participants noted measurement should be quick, inexpensive and focused on local solutions. Furthermore, programs should use existing data to generate mathematical models to understand what levels of never treatment may compromise LF elimination goals or trigger programmatic action

"Our interventions are still here to support communities during the pandemic": Resuming mass drug administration for neglected tropical diseases after COVID-19 implementation delays.

The COVID-19 pandemic disrupted essential health services, including those provided by national neglected tropical disease (NTD) programs. Most mass drug administration (MDA) programs were postponed for 6-12 months following World Health Organization guidance released in April 2020 to temporarily halt NTD programs and launch necessary COVID-19 precautions. While NTD-endemic countries have since resumed MDA activities, it is critical to understand implementers' perspectives on the key challenges and opportunities for program relaunch, as these insights are critical for maximizing gains towards disease control and elimination during public health emergencies. Using data from using online surveys and focus group discussions, this mixed-methods study sought perspectives from Ministry of Health NTD Program Managers and implementing partners from non-governmental organizations working in sub-Saharan Africa. Data analysis revealed that findings converged around several main themes: disruptions for MDA programs included resource shortages due to prioritization of pandemic response, challenges adhering to COVID-19 safety protocols, and community hesitancy due to coronavirus transmission fears. Identified solutions for restarting MDA programs focused on adapting intervention delivery and packaging to minimize disease transmission, embracing technology to optimize intervention planning and delivery, and identifying opportunities to promote program integration between pandemic response strategies and NTD campaign delivery. Findings identifies key challenges due to disruptions to NTD program delivery and provide strategic recommendations for endemic countries to build resilient programs that can continue to perform during and beyond global pandemics

Evaluating dengue burden in Africa in passive fever surveillance and seroprevalence studies: protocol of field studies of the Dengue Vaccine Initiative.

INTRODUCTION: Dengue is an important and well-documented public health problem in the Asia-Pacific and Latin American regions. However, in Africa, information on disease burden is limited to case reports and reports of sporadic outbreaks, thus hindering the implementation of public health actions for disease control. To gather evidence on the undocumented burden of dengue in Africa, epidemiological studies with standardised methods were launched in three locations in Africa. METHODS AND ANALYSIS: In 2014-2017, the Dengue Vaccine Initiative initiated field studies at three sites in Ouagadougou, Burkina Faso; Lambaréné, Gabon and Mombasa, Kenya to obtain comparable incidence data on dengue and assess its burden through standardised hospital-based surveillance and community-based serological methods. Multidisciplinary measurements of the burden of dengue were obtained through field studies that included passive facility-based fever surveillance, cost-of-illness surveys, serological surveys and healthcare utilisation surveys. All three sites conducted case detection using standardised procedures with uniform laboratory assays to diagnose dengue. Healthcare utilisation surveys were conducted to adjust population denominators in incidence calculations for differing healthcare seeking patterns. The fever surveillance data will allow calculation of age-specific incidence rates and comparison of symptomatic presentation between patients with dengue and non-dengue using multivariable logistic regression. Serological surveys assessed changes in immune status of cohorts of approximately 3000 randomly selected residents at each site at 6-month intervals. The age-stratified serosurvey data will allow calculation of seroprevalence and force of infection of dengue. Cost-of-illness evaluations were conducted among patients with acute dengue by Rapid Diagnostic Test. ETHICS AND DISSEMINATION: By standardising methods to evaluate dengue burden across several sites in Africa, these studies will generate evidence for dengue burden in Africa and data will be disseminated as publication in peer-review journals in 2018

Geostatistical modelling of the distribution, risk and burden of podoconiosis in Kenya

Background Understanding and accurately predicting the environmental limits, population at risk and burden of podoconiosis are critical for delivering targeted and equitable prevention and treatment services, planning control and elimination programs, and implementing tailored case finding and surveillance activities. Methods This is secondary analysis of nationwide podoconiosis mapping survey in Kenya. We combined national representative prevalence survey data of podoconiosis with climate and environmental data, overplayed with population figures in a geostatistical modelling framework, to predict the environmental suitability, population living in at-risk areas and number of cases of podoconiosis in Kenya. Results In 2020, the number of people living with podoconiosis in Kenya was estimated to be 9,344 people (95% uncertainty interval, 4,222 to 17,962). The distribution of podoconiosis varies by geography and three regions (Eastern, Nyanza and Western) represent over 90% of the absolute number of cases. High environmental suitability for podoconiosis was predicted in four regions of Kenya (Coastal, Eastern, Nyanza and Western). In total, 2.2 million people live in at-risk areas and 4.2% of the total landmass of Kenya is environmentally predisposed for podoconiosis. Conclusions The burden of podoconiosis is relatively low in Kenya and is mostly restricted to certain small geographical areas. Our results help guide targeted prevention and treatment approaches through local planning, spatial targeting and tailored surveillance activities

Mapping of podoconiosis cases and risk factors in Kenya: a nationwide cross-sectional study

Podoconiosis is a type of tropical lymphedema that is clinically distinguished from lymphatic filariasis (LF) because it is ascending and commonly bilateral but asymmetric. The disease is a result of a genetically determined inflammatory reaction to long-term exposure to mineral particles in irritant red clay soils derived mainly from volcanic soils. We conducted the first nationwide mapping of the prevalence and risk factors of podoconiosis in Kenya. We performed a population-based cross-sectional survey to determine the national prevalence of podoconiosis and included 6,228 individuals from 48 villages in 24 sub-counties across 15 counties. Participants answered a questionnaire about the history of symptoms compatible with podoconiosis, received a point-of-care antigen test, and underwent a physical examination if they had lymphedema. A confirmed case of podoconiosis was defined as a case in a resident of the study village who had lower limb bilateral and asymmetric lymphedema lasting more than 1 year, negative test results for Wuchereria bancrofti antigen, and other causes of lymphedema ruled out. Of all the individuals surveyed, 89 had lymphedema; of those, 16 of 6228 (0.3%; 95% confidence interval [CI], 0.1–0.5) were confirmed to have podoconiosis. A high prevalence of podoconiosis was found in western (Siaya, 3.1%; Busia, 0.9%) and central (Meru, 1.1%) regions, and a low prevalence was observed in northern (Marsabit, 0.2%), eastern (Makueni, 0.2%), and coastal (Tana River, 0.1%) regions. The identified risk factors were age 56 years or older (adjusted odds ratio [aOR], 5.66; 95% CI, 2.32–13.83; P < 0.001) and rarely wearing shoes (aOR, 18.92; 95% CI, 4.55–78.71; P < 0.001). These results indicated that the podoconiosis prevalence is low and localized in Kenya; therefore, elimination is achievable if appropriate disease prevention, management, and behavioral strategies are promoted

Precision mapping of schistosomiasis and soil-transmitted helminthiasis among school age children at the coastal region, Kenya.

BackgroundAccurate mapping of schistosomiasis (SCH) and soil transmitted helminths (STH) is a prerequisite for effective implementation of the control and elimination interventions. A precision mapping protocol was developed and implemented in the coastal region of Kenya by applying the current World Health Organization (WHO) mapping guide at a much lower administrative level (ward).MethodsA two-stage cluster survey design was undertaken, with 5 villages in each ward selected. From within each village 50 households were randomly selected, and a single child between the ages of 8 and 14 sampled following appropriate assent. The prevalence and intensity of infection of Schistosoma mansoni and STH were determined using the Kato-Katz method (single stool, duplicate slides) and urine filtration for S. haematobium.ResultsOf the 27,850 school age children sampled, 6.9% were infected with at least one Schistosoma species, with S. haematobium being the most common 6.1% (95% CI: 3.1-11.9), and Tana River County having highest prevalence 19.6% (95% CI: 11.6-31.3). Prevalence of any STH infection was 5.8% (95% CI: 3.7-8.9), with Lamu County having the highest prevalence at 11.9% (95% CI: 10.0-14.1). The most prevalent STH species in the region was Trichuris trichiura at 3.1% (95% CI: 2.0-4.8). According to the WHO threshold for MDA implementation, 31 wards (in 15 sub-Counties) had a prevalence of ≥10% for SCH and thus qualify for annual MDA of all age groups from 2 years old. On the other hand, using the stricter Kenya BTS MDA threshold of ≥2%, 72 wards (in 17 sub-Counties) qualified for MDA and were targeted for treatment in 2021.ConclusionsThe precision mapping at the ward level demonstrated the variations of schistosomiasis prevalence and endemicity by ward even within the same sub-counties. The data collected will be utilized by the Kenyan Ministry of Health to improve targeting