The Global Economic and Health Burden of Human Hookworm Infection

Abstract

Background: Even though human hookworm infection is highly endemic in many countries throughout the world, its global economic and health impact is not well known. Without a better understanding of hookworm's economic burden worldwide, it is difficult for decision makers such as funders, policy makers, disease control officials, and intervention manufacturers to determine how much time, energy, and resources to invest in hookworm control.

Methodology/principle findings: We developed a computational simulation model to estimate the economic and health burden of hookworm infection in every country, WHO region, and globally, in 2016 from the societal perspective. Globally, hookworm infection resulted in a total 2,126,280 DALYs using 2004 disability weight estimates and 4,087,803 DALYs using 2010 disability weight estimates (excluding cognitive impairment outcomes). Including cognitive impairment did not significantly increase DALYs worldwide. Total productivity losses varied with the probability of anemia and calculation method used, ranging from $7.5 billion to $138.9 billion annually using gross national income per capita as a proxy for annual wages and ranging from $2.5 billion to $43.9 billion using minimum wage as a proxy for annual wages.

Conclusion: Even though hookworm is classified as a neglected tropical disease, its economic and health burden exceeded published estimates for a number of diseases that have received comparatively more attention than hookworm such as rotavirus. Additionally, certain large countries that are transitioning to higher income countries such as Brazil and China, still face considerable hookworm burden.

Fig 1. Impact of disability weight (DW) estimates on A) global DALYs, and B) global productivity losses across varying levels of anemia calculated using Method 1 (including cognitive impairment).

The lower end of the range is the total burden assuming a low probability of anemia, while the upper end assumed a high probability of anemia. The 2004 DW and 2010 DW represent results with the published DW estimates and +/- 10% indicates adjustment to these values.

Fig 2

Hookworm-associated productivity losses in 2016 by annual wage proxy used for A) Africa, B) the Americas, C) Eastern Mediterranean, D) Europe, E) South-East Asia, and F) Western Pacific regions.