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.

Milling reduces the goitrogenic potential of cassava

Cyanide exposure from consumption of insufficiently processed cassava has been implicated in aggravating iodine deficiency disorders (IDD). The cyanide metabolite, thiocyanate (SCN) may interfere with iodine (I) uptake of the thyroid gland. A study on 217 women in an IDD endemic area in western Tanzania showed that 98% consumed cassava daily. Total and visible goitre rates were 72.8% and 13.3%, respectively. Median urinary iodine was 3.6 micrograms/dl indicating moderate iodine deficiency. Processing methods which remove cyanogens from cassava roots have changed with time. Urinary thiocyanate (mean; 128 mumol/l) was moderately increased, but women who frequently milled cassava had significantly lower urinary thiocyanate levels. This indicates that mechanical milling could reduce the goitrogenic potential of cassava and we conclude that IDD in the studied area is mainly due to iodine deficiency and sustainable iodine supplementation should be given highest priority.

Adherence to iron supplementation during pregnancy in Tanzania: determinants and hematologic consequences

Limited adherence to iron supplementation is thought to be a major reason for the low effectiveness of anemia-prevention programs. In rural Tanzania, women at 21-26 wk of gestation were randomly given either 120 mg of a conventional (Con) iron supplement or 50 mg of a gastric-delivery-system (GDS) iron supplement for 12 wk. Adherence was assessed by using a pill bottle equipped with an electronic counting device. Adherence in the GDS group was 61% compared with 42% for the Con group. In both groups, women experiencing side effects had about one-third lower adherence. Fewer side effects were observed in the GDS group. In a subgroup of women with a low initial hemoglobin concentration (< or = 120 g/L), the response to the iron supplements suggested that both of the applied doses were unnecessarily high for adequate hematologic response in a population with a marginal hemoglobin concentration. The GDS group appeared to require a dose one-fourth as high as that of the Con group for an equal effect on improving hemoglobin to normal concentrations.

Prevalence of xerophthalmia in relation to nutrition and general health in preschool-age children in three regions of Tanzania

Integrated nutrition/health surveys were carried out in Mbeya, Iringa and Kagera Regions in Tanzania in which a total of 12,880 children were examined for the presence of xerophthalmia. Xerophthalmia was found to be a problem of public health significance in two of the three regions surveyed where the prevalence of active corneal xerophthalmic lesions was above the criteria set by WHO. Because of clustering of the children with Bitot's spots, corneal xerosis/ulceration and corneal scarring, only certain villages or groups of villages could be regarded as areas where xerophthalmia is a problem. The results of the ophthalmological examinations are discussed in relation to the nutritional status of the children as measured by anthropometric indices, serum levels of retinol-binding protein and prealbumin, haematological parameters, and vaccination status.