Soil-Transmitted Helminths in Southwestern China: A Cross-Sectional Study of Links to Cognitive Ability, Nutrition, and School Performance among Children

Abstract

BackgroundEmpirical evidence suggests that the prevalence of soil-transmitted helminth (STH) infections in remote and poor rural areas is still high among children, the most vulnerable to infection. There is concern that STH infections may detrimentally affect children’s healthy development, including their cognitive ability, nutritional status, and school performance. Medical studies have not yet identified the exact nature of the impact STH infections have on children. The objective of this study is to examine the relationship between STH infections and developmental outcomes among a primary school-aged population in rural China.Methodology/Principal FindingsWe conducted a large-scale survey in Guizhou province in southwest China in May 2013. A total of 2,179 children aged 9-11 years living in seven nationally-designated poverty counties in rural China served as our study sample. Overall, 42 percent of the sample’s elementary school-aged children were infected with one or more of the three types of STH—Ascaris lumbricoides (ascaris), Trichuris trichuria (whipworm) and the hookworms Ancylostoma duodenale or Necator americanus. After controlling for socioeconomic status, we observed that infection with one or more STHs is associated with worse cognitive ability, worse nutritional status, and worse school performance than no infection. This study also presents evidence that children with Trichuris infection, either infection with Trichuris only or co-infected with Trichuris and Ascaris, experience worse cognitive, nutritional and schooling outcomes than their uninfected peers or children infected with only Ascaris.Conclusions/SignificanceWe find that STH infection still poses a significant health challenge among children living in poor, rural, ethnic areas of southwest China. Given the important linkages we find between STH infection and a number of important child health and educational outcomes, we believe that our results will contribute positively to the debate surrounding the recent Cochrane report.

Human Capital and China’s Future Growth

“…Primary and middle schools are free in China. However, whereas most developed countries, and many developing countries, do not charge tuition for high school, China charges a minimum of $160 (in US dollars) per year, which is 27 percent of rural per capita income (Liu et al 2009). Indeed, academic high school tuition rates in China are among the highest in the world (Liu et al 2009).…”

“…However, whereas most developed countries, and many developing countries, do not charge tuition for high school, China charges a minimum of $160 (in US dollars) per year, which is 27 percent of rural per capita income (Liu et al 2009). Indeed, academic high school tuition rates in China are among the highest in the world (Liu et al 2009). College tuition fees also are burdensome for students from poor rural areas, and students from those areas often do not qualify for need-based financial aid (Li, Meng, Shi, and Wu 2013;Loyalka et al 2013).…”

“…In competitive systems, even outside of China, dropout rates are known to be high (Battin-Pearson et al 2000). In addition, and in no small part connected to the high pressure in China's schools, high levels of anxiety and depression have been shown to plague youth in China (Wang et al 2015). Mental health problems are associated with lower performance and dropping out .…”

Effect of Deworming on Indices of Health, Cognition, and Education Among Schoolchildren in Rural China: A Cluster-Randomized Controlled Trial

“…[1][2][3] Observational studies have found that chronic infection with STHs among school-aged children is associated with malnutrition and impaired growth, 4-6 cognitive impairment, 7,8 and lower school attendance. 9 These associations suggest that, in theory, reducing STH infection in children has the potential to improve nutrition and growth (i.e., hemoglobin levels, weight, height), cognitive abilities (i.e., working memory, processing speed), and school performance (i.e., school attendance, standardized test scores).…”

Досвід Проведення Дегельмінтизації У Дітей

“…Серед них 42 % були інфіковані тим чи іншим видом круглих черв'яків (аскарида, волосоголов, кривоголовка дванадцятипала, некатор). Встановлено, що паразитар-на інфекція у дитини була асоційована із гіршими когні-тивними здатностями, нижчим нутритивним статусом, поганою шкільною успішністю [6]. Підтвердження не-гативного впливу паразитозу на розвиток дитини отри-мали і дослідники з Кенії, які вивчали поширеність та дію гельмінтів на зростаючий організм дитини протягом перших трьох років життя.…”