The cost effectiveness of strategies for the treatment of intestinal parasites in immigrants

Background Currently, more than 600,000 immigrants enter the United States each year from countries where intestinal parasites are endemic. At entry persons with parasitic infections may be asymptomatic, and stool examinations are not a sensitive method of screening for parasitosis. Albendazole is a new, broad-spectrum antiparasitic drug, which was approved recently by the Food and Drug Administration. International trials have shown albendazole to be safe and effective in eradicating many parasites. In the United States there is now disagreement about whether to screen all immigrants for parasites, treat all immigrants presumptively, or do nothing unless they have symptoms. Methods We compared the costs and benefits of no preventive intervention (watchful waiting) with those of universal screening or presumptive treatment with 400 mg of albendazole per day for five days. Those at risk were defined as immigrants to the United States from Asia, the Middle East, sub-Saharan Africa, Eastern Europe, and Latin America and the Caribbean. Cost effectiveness was expressed both in terms of the cost of treatment per disability-adjusted life-year (DALY) averted (one DALY is defined as the loss of one year of healthy life to disease) and in terms of the cost per hospitalization averted. Results As compared with watchful waiting, presumptive treatment of all immigrants at risk for parasitosis would avert at least 870 DALYs, prevent at least 33 deaths and 374 hospitalizations, and save at least $4.2 million per year. As compared with watchful waiting, screening would cost $159,236 per DALY averted. Conclusions Presumptive administration of albendazole to all immigrants at risk for parasitosis would save lives and money. Universal screening, with treatment of persons with positive stool examinations, would save lives but is less cost effective than presumptive treatment. (N Engl J Med 1999;340:773-9.) (C)1999, Massachusetts Medical Society.