Coverage and cost of iodized oil capsule distribution in Tanzania

Distribution of oral iodized oil capsules (IOC) is an important intervention in areas with iodine deficiency disorders (IDD) and low coverage of iodized salt. The mean reported coverage of 57 IOC distribution campaigns from 1986-1994 of people aged 1-45 years in 27 districts of Tanzania was 64% (range 20-96%). This declined over subsequent distribution rounds. However, due to delayed repeat distribution, only 43% of person-time was covered, based on the programme objective of giving two IOC (total 400 mg iodine) at 2-year intervals. Three different capsule distribution strategies used in 20 distribution rounds in 1992-1993 were analyzed in depth. Withdrawal of financial support for district distribution expenses under the 'district team' strategy, and the subsequent change to integrated 'primary health care' distribution, increased delays and capsule wastage. The third, more vertical strategy, 'national and district teams', accomplished rapid distribution of IOC about to expire and subsequently a return to the initial 'district team' allowance strategy was made. Annual cost of 'district team' distribution was 26 cents per person (400 mg iodine/2 years). Cost analysis revealed that the IOC itself accounts for more than 90% of total costs at the levels of coverage achieved. IOC will be important in the elimination of IDD in target areas of severe iodine deficiency and insufficient use of iodized salt, provided that high coverage can be achieved. Campaign distribution of medication with high item cost and long distribution intervals may be more cost-effectively performed if separated from regular PHC services at their present resource level. However, motivating health workers and community leaders to do adequate social mobilization remains crucial even if logistics are vertically organized. Insufficient support of distribution expenses and health education may lead to overall wastage of resources.