The Burden of Parasitic Zoonoses in Nepal: A Systematic Review

Abstract

BackgroundParasitic zoonoses (PZs) pose a significant but often neglected threat to public health, especially in developing countries. In order to obtain a better understanding of their health impact, summary measures of population health may be calculated, such as the Disability-Adjusted Life Year (DALY). However, the data required to calculate such measures are often not readily available for these diseases, which may lead to a vicious circle of under-recognition and under-funding.MethodologyWe examined the burden of PZs in Nepal through a systematic review of online and offline data sources. PZs were classified qualitatively according to endemicity, and where possible a quantitative burden assessment was conducted in terms of the annual number of incident cases, deaths and DALYs.Principal FindingsBetween 2000 and 2012, the highest annual burden was imposed by neurocysticercosis and congenital toxoplasmosis (14,268 DALYs [95% Credibility Interval (CrI): 5450–27,694] and 9255 DALYs [95% CrI: 6135–13,292], respectively), followed by cystic echinococcosis (251 DALYs [95% CrI: 105–458]). Nepal is probably endemic for trichinellosis, toxocarosis, diphyllobothriosis, foodborne trematodosis, taeniosis, and zoonotic intestinal helminthic and protozoal infections, but insufficient data were available to quantify their health impact. Sporadic cases of alveolar echinococcosis, angiostrongylosis, capillariosis, dirofilariosis, gnathostomosis, sparganosis and cutaneous leishmaniosis may occur.Conclusions/SignificanceIn settings with limited surveillance capacity, it is possible to quantify the health impact of PZs and other neglected diseases, thereby interrupting the vicious circle of neglect. In Nepal, we found that several PZs are endemic and are imposing a significant burden to public health, higher than that of malaria, and comparable to that of HIV/AIDS. However, several critical data gaps remain. Enhanced surveillance for the endemic PZs identified in this study would enable additional burden estimates, and a more complete picture of the impact of these diseases.

Data-driven methods for imputing national-level incidence in global burden of disease studies

“…Imputation will never be a perfect substitute for actual data 28 , 29 . We evaluated the predictive accuracy of various methods to impute missing national-level disease parameters.…”

The global burden of listeriosis: a systematic review and meta-analysis

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Modelling the risk of Taenia solium exposure from pork produced in western Kenya

“…In Nepal it is estimated that 0.543 (95% C.I. 0.207–1.0543) DALYs are lost per 1000 person years [18]. In the majority of cases, the only NCC-associated sequela considered in DALY calculations to date has been epilepsy, while severe headache was also included in Mexico [4, 5, 17, 18].…”

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