Interventions to Reduce Worm Infections and Their Impacts
In China, school-based educational activities led to reduced prevalence of worm infection; in India, 6-monthly deworming had little effect on mortality or weight in young children.
Intestinal worms — soil-transmitted helminths — are common in rural areas with inadequate sanitation. Mass drug treatment has been used for control but does not prevent reinfection. Two recent studies conducted in Asia address worm infections in children.
To determine whether health-education programs can change behavior and reduce reinfection, Bieri and colleagues conducted a cluster-randomized intervention trial involving 38 rural schools in southern Hunan province, China, during the 2010–2011 academic year. The schools were assigned to an intervention package (an educational video complemented by classroom discussions, written materials with cartoons, and drawing and essay-writing competitions) or a control package (a standard health-education poster displayed in schools). At baseline, all participants — children in grades 4 and 5 — completed a questionnaire about knowledge, attitudes, and practices (KAP), provided a fecal sample, and received 400 mg of albendazole.
Of 1924 students enrolled, 89% were included in the final analysis. At baseline, prevalence of infection was 10.4% in the control schools and 10.0% in the intervention schools. After the 9-month intervention, incidence was 8.4% in control and 4.1% in intervention schools (50% efficacy). Knowledge about helminths, based on follow-up KAP questionnaire scores, was 90% higher in the intervention group than in the control group. Intervention-group children were more likely than control-group children to wash their hands after toilet use (98.9% vs. 54.2%; P=0.005).
In India, Awasthi and colleagues conducted a 5-year, cluster-randomized study to examine the feasibility of delivering mass treatment, such as vitamin A, every 6 months using Integrated Child Development Service (ICDS) infrastructure. They also assessed the effects of 6-monthly albendazole on mortality and weight. The study, which began in January 1999, involved approximately 2 million children aged 1 to 6 years who were attending ICDS-staffed daycare centers in rural Uttar Pradesh.
Among 5165 children with complete information on all assays and questionnaire replies, fecal assays during the second half of the study revealed nematode (Ascaris or hookworm) eggs in 16% of albendazole-group children, compared with 36% of control-group children. Infection, when present, was generally light. Risk for death between ages 1 and 6 was similar between groups (2.5% in the albendazole group and 2.6% in the control group), as were weight, height, and hemoglobin level.
CITATION(S):
Bieri FA et al. Health-education package to prevent worm infections in Chinese schoolchildren. N Engl J Med 2013 Apr 25; 368:1603.
Awasthi S et al. Population deworming every 6 months with albendazole in 1 million pre-school children in north India: DEVTA, a cluster-randomised trial. Lancet 2013 Mar 14; [e-pub ahead of print].
Garner P et al. DEVTA: Results from the biggest clinical trial ever. Lancet 2013 Mar 14; [e-pub ahead of print].
