Hookworm, Ascaris lumbricoides infection and polyparasitism associated with poor cognitive performance in Brazilian schoolchildren.

OBJECTIVE: To investigate the relationship between hookworm and Ascaris lumbricoides infection and performance on three subsets of the Wechsler Intelligence Scale for Children - third edition (WISC-III) (Digit Span, Arithmetic and Coding) and Raven Colored Progressive Matrices. METHODS: Cross-sectional study of 210 children between the ages of 6 and 11 years in Americaninhas, Minas Gerais, Brazil. Separate proportional odds models were used to measure the association between the intensity of helminth infections and poor performance on each of the four cognitive tests. RESULTS: After adjusting for sex, age, socioeconomic status and other helminth infections, moderate-to-high-intensity hookworm infection was associated with poor performance on the WISC-III Coding subtest [OR = 3.20; 95% confidence interval (CI) = 1.43-7.17], low intensity of hookworm infection was associated with poor performance on the WISC-III Coding subtest [odds ratio (OR) = 3.71; 95% CI = 1.80-7.66] and moderate-to-high-intensity A. lumbricoides infection was associated with poor performance on the Raven test (OR = 2.03; 95% CI = 1.04-3.99), all in comparison with uninfected children. Children co-infected with A. lumbricoides infection and hookworm infection had greater odds of poor performance on some WISC-III subtests than children with only A. lumbricoides infection. CONCLUSIONS: These findings suggest that hookworm infection may be associated with poorer concentration and information processing skills, as measured on the WISC-III Coding subtest, and that A. lumbricoides infection may be associated with poorer general intelligence, as measured through the Raven Colored Progressive Matrices. This study also presents evidence that polyparasitized children experience worse cognitive outcomes than children with only one helminth infection.

Recent progress in integrated neglected tropical disease control.

Three years have passed since the publication of the first of a series of policy papers, which first highlighted the under-appreciated global burden of the neglected tropical diseases (NTDs) and then outlined a rationale for linking vertical control strategies for the seven most prevalent NTDs in a cost-effective pro-poor package of preventive chemotherapy. Since then, global advocacy for these conditions has increased and, with it, new funds for scale-up of integrated NTD control in sub-Saharan Africa. Recent speeches by the Director General of the World Health Organization at regional meetings have referred to NTDs as important global health priorities (www.who.int/dg/speeches/2007). Outlined here is a summary of the recent progress in global efforts to integrate NTD control, with an emphasis on the challenges that lie ahead.