The far-reaching health consequence of vitamin A deficiency is well-substantiated by numerous well-designed scientific studies (1,2). Meta-analysis of a number of trials has clearly demonstrated that as much as 23% reduction in mortality of children could be achieved by improving vitamin A status (3). Several studies have established that vitamin A deficiency is a major public-health problem in Ethiopia (4-10). Except in the southern region where studies have consistently shown low levels of vitamin A deficiency (4,10), the problem has continued to constitute a major public-health concern in other regions. In some regions, close to 8% prevalence rate of Bitot's spot (clinical vitamin A deficiency) was reported, perhaps the highest rate ever recorded in the world (6). The fifth nutrition situation report of the Standing Committee on Nutrition of the United Nations indicates that the prevalence of xerophthalmia in Ethiopia is the highest in the world (11).
Cognizant of the wide-scale prevalence and enormous health impacts, interventions were initiated as early as in 1960 in Ethiopia. During 1969-1973, a pilot intervention study in two towns--one with nutrition education and the other with vitamin A capsule distribution--emphasized the value of these interventions, and following this, disease-targeted vitamin A supplementation, along with nutrition education, was initiated. The nationwide vitamin A supplementation began in 1995 as a component of Expanded Programme on Immunization (EPI), and starting from 1997, vitamin A supplementation was effected through campaigns either integrated with the National Immunization Days or as a stand-alone activity. Initially, the coverage was good but later the coverage dropped substantially as a result of deaths occurring during the supplementation. While squeezing the contents of the capsule during oral dosing, in some rare instances, the entire capsules slipped into the mouth of children and choked them by sticking to esophagus and blocking air passage. At the time of this survey, an enhanced outreach strategy, incorporating deworming and other health interventions, along with vitamin A supplementation, was being implemented in three regions.
The primary cause of vitamin A deficiency is inadequate dietary consumption of vitamin A and/ or suboptimal use of the nutrient in the body. A number of secondary factors contribute to insufficient dietary intake of vitamin A. Inadequate production of vitamin A-rich foods, lack of income to purchase, unavailability of vitamin A-rich foods in markets, a large family size, high maternal parity levels, low level of maternal education, low levels of awareness of the importance of vitamin A, and illness are some secondary factors that are presumed to contribute to inadequate consumption of vitamin A in developing countries.
As the risk factors and determinants of vitamin A are context-specific (socioeconomic, cultural, environmental, etc.), variations in factors contributing to vitamin A deficiency exist among countries, regions, and localities, underlining the need to assess country/region/area-specific risk factors. Knowledge on such specific risk factors enables implementers and policy-makers to design and implement effective interventions. Unfortunately, studies relating to country and region or area-specific causes of vitamin A in Ethiopia are scarce, and hence, substantive information regarding factors contributing to vitamin A deficiency is lacking. The aim of this study was to partially fill the information gap on causes of vitamin A deficiency by providing information on some demographic and health-related risk factors.
MATERIALS AND METHODS
Survey design and sampling
Multi-stage, cluster-sampling approach and cross-sectional design were employed in the study. Nine of the 11 regional administrative states that constitute the Federal Government of Ethiopia were included in the survey (two regions were excluded due to security reasons). In each region, 30 clusters (villages) were randomly selected, and blood samples were collected from five systematically-selected children, bringing the regional sample size to 150 children and the national sample size to 1,350 children (nine regions). The sample size of 150 children per region was determined based on 44% prevalence rate of deficient serum retinol levels reported in the 1980/1981 national study that is p=44%, confidence interval=95%, worst acceptable=54%, and clustering effect of 2. Interviews pertaining to household, maternal and child characteristics presumed to contribute to vitamin A deficiency …