A scoping review of burden of disease studies estimating disability-adjusted life years due to Taenia solium

Abstract

Background Taenia solium is the most significant global foodborne parasite and the leading cause of preventable human epilepsy in low and middle-income countries in the form of neurocysticercosis. Objectives This scoping review aimed to examine the methodology of peer-reviewed studies that estimate the burden of T. solium using disability-adjusted life years. Eligibility criteria Studies must have calculated disability-adjusted life years relating to T. solium. Charting methods The review process was managed by a single reviewer using Rayyan. Published data relating to disease models, data sources, disability-adjusted life years, sensitivity, uncertainty, missing data, and key limitations were collected. Results 15 studies were included for review, with seven global and eight national or sub-national estimates. Studies primarily employed attributional disease models that relied on measuring the occurrence of epilepsy before applying an attributable fraction to estimate the occurrence of neurocysticercosis-associated epilepsy. This method relies heavily on the extrapolation of observational studies across populations and time periods; however, it is currently required due to the difficulties in diagnosing neurocysticercosis. Studies discussed that a lack of data was a key limitation and their results likely underestimate the true burden of T. solium. Methods to calculate disability-adjusted life years varied across studies with differences in approaches to time discounting, age weighting, years of life lost, and years of life lived with disability. Such differences limit the ability to compare estimates between studies. Conclusions This review illustrates the complexities associated with T. solium burden of disease studies and highlights the potential need for a burden of disease reporting framework. The burden of T. solium is likely underestimated due to the challenges in diagnosing neurocysticercosis and a lack of available data. Advancement in diagnostics, further observational studies, and new approaches to parameterising disease models are required if estimates are to improve.

The challenges of detecting Taenia solium and neurocysticercosis in low and middle‐income countries: A scoping review of Lao People's Democratic Republic

“…In particular, the association between T. solium , neurocysticercosis and epilepsy has not been sufficiently described in Southeast Asia. This association is the cornerstone of almost all neurocysticercosis burden of disease estimates that inform decision‐making, yet there are scant data from the region [57]. Due to the difficulty in accessing neurologists and the advanced imaging required for diagnosis [11], it is expected that this important feature will remain unclear for some time to come.…”

Risk mapping for Taenia solium: Applying multicriteria decision analysis in Lao PDR

“…The WHO NTD Roadmap 2021–2030 calls for intensified control of T. solium in hyperendemic areas [28]. However, the epidemiological picture is currently cloudy in many endemic countries and the global burden of disease is dominated by research from Africa and South America [29]. The hyperendemic areas referenced by WHO have often not yet been identified and endemic countries frequently lack the resources to conduct national prevalence surveys or maintain expansive surveillance programmes.…”

“…The WHO NTD Roadmap 2021-2030 calls for intensified control of T. solium in hyperendemic areas [28]. However, the epidemiological picture is currently cloudy in many endemic countries and the global burden of disease is dominated by research from Africa and South America [29].…”

Global research on cysticercosis and neurocysticercosis: A bibliometric analysis

“…Neurocysticercosis is endemic to much of Asia, sub-Saharan Africa, and Latin America, where it constitutes a prominent public health problem associated with poverty and poor sanitary and hygienic conditions ( 6 ). Its prevalence is probably underestimated due both to the difficulty in diagnosing it (since it often produces mild and non-specific symptoms) and the lack of observational studies in different populations and countries ( 7 ). The estimated burden of human cysticercosis, according to systematic reviews or similar studies published from 2010 to 2015, is 2.78 million disability-adjusted life years (DALYs) (95% uncertainty intervals 2.14-3.61 million) ( 8 ).…”