Forecasted Trends in the Burden of Trichuris trichiura in Afghanistan, Iran, and Pakistan: A Regional Epidemiological Modeling Study
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Abstract
Background: Trichuriasis, caused by Trichuris trichiura, remains a significant public health concern in many low- and middle-income countries. Understanding its future burden is essential for informed resource allocation and intervention planning. We aimed to model and compare the projected age-standardized prevalence rates (ASPR) of trichuriasis in Afghanistan, Iran, and Pakistan from 2023 to 2040.
Methods: We extracted sex‑specific ASPR data for T. trichiura from 1990 to 2023 from the Global Burden of Disease Study 2023 (GBD 2023). A cubic spline regression model was then fitted to the historical data using a least‑squares approach. The calibrated model was subsequently used to project ASPR and its 95% confidence intervals (CIs) through 2040 for each country and sex.
Results: In 2023, Pakistan had a substantially higher ASPR of 8,186.1 per 100,000, approximately 19 and 29 times higher than Afghanistan (424.7) and Iran (284.6), respectively. By 2040, all countries are projected to experience declines. Afghanistan shows the steepest relative decline, with a reduction of 61.9%, reaching an ASPR of 161.7 per 100,000 by 2040, and Pakistan the largest absolute reduction (45.2% to 4,488.9 per 100,000). Minor but consistent male-biased prevalence disparities were observed throughout the projection period.
Conclusion: While the burden of trichuriasis is projected to decline substantially in all three countries by 2040, stark disparities in baseline prevalence and rates of decline persist. Pakistan is projected to retain a disproportionately high absolute burden. These findings underscore the need for intensified, context-specific public health strategies, including sustained mass drug administration (MDA) and improvements in water, sanitation, and hygiene (WASH) infrastructure, to accelerate progress towards elimination.
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References
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