Evaluation of two years of mass chemotherapy against ascariasis in Hamadan, Islamic Republic of Iran.

OBJECTIVE: To evaluate the mass treatment of ascariasis in rural areas of Hamadan Province, Islamic Republic of Iran.

METHODS: A control programme in rural areas of Hamadan Province, which began in November 1997, involved giving all persons a single dose of 400 mg albendazole at intervals of three months. The efficacy of the treatment was evaluated by the formalin-ether concentration technique for stool examination and by the Stoll quantitative method.

FINDINGS: The average rate of infection with Ascaris before treatment was 53.3%, ranging from 40% in Hamadan district to 75% in Toysercan. Two areas, Malayer and Nahavand, were excluded from the programme because the infection rates were only 13% and 4%, respectively. After two years of mass treatment the infection rate had decreased to 6%. The proportion of positive cases excreting only unfertilized eggs increased to 32%. No side-effects of mass treatment were observed.

CONCLUSION: Systematic mass treatment giving high coverage proved to be very effective in the control of ascariasis, notwithstanding a lack of other preventive measures.