The authors' stated purpose was to assess the efficacy of a common treatment for a widespread public health problem—parasitic infections. With over 4 billion people at risk, 1.5 billion active infections, and 400 million in morbidity, Ascaris lumbricoides, Trichuris trichiura, and Necator americanus present a significant world health burden. Periodic treatment with a one-time dose of 400 mg albendazole is often used to reduce a community's disease burden, but reinfection is common and resistance is a concern. This prospective experimental study analyzed the efficacy of this treatment in 7 countries: Brazil, Cambodia, Cameroon, India, Ethiopia, Tanzania, and Vietnam.
Enrollment totaled 2319 across all of the sites and included children 4 to 18 years old, requiring initial stool samples to contain over 150 eggs per gram, and also a minimum of 250 participants per country. After the initial stool sample, participants were treated with 400 mg of albendazole and a repeat stool sample was taken 14 to 30 days later. Of the 2319 participants, 485 were lost to follow-up. The McMaster technique was used to quantify egg burden in stool samples, which involved inspection with microscopy.
At follow-up, cure rates were found to be 98% for A lumbricoides, 87% for N americanus, and 47% for T trichiura. Fecal egg count reduction showed similar declines in each species. The authors highlight the need for continued monitoring of treatment effectiveness in order to avoid resistance and maintain effective treatment. The poor efficacy against T trichiura was thought to result from growing resistance, and the authors cited genetic markers in this species associated with resistance.
(PLoS Negl Trop Dis. 2011:5;e948) J Vercruysse, JM Behnke, M Albonico, et al.
Prepared by Anil Menon, MD, UTMB/NASA Aerospace Medicine Fellow, Galveston, TX, USA