Impact of massive doses of vitamin A on nutritional blindness in Bangladesh

Abstract

Impact of 6-monthly massive dosings of preschool-age children with oral vitamin A (VAC: 200,000 IU of oil soluble retinyl palmitate with 40 IU vitamin E) was evaluated in Bangladesh. In 100 sites, 11,889 households were visited and eyes of 22,335 children aged 3-71 mo were examined. About half the rural target population and less than 20% urban slum population were being reached. Risk of night blindness was halved for children reportedly given VAC, although 2.5% of the reportedly protected population were still night blind. There was no significant reduction in prevalence of Bitot's spot. Risk of corneal ulcers or keratomalacia (X3A/B) was 2.7 times higher in children not given VAC. Based on reported coverage, efficacy of protection against potentially blinding corneal lesions was 63%. For maximum impact on eye lesions, massive dosing with vitamin A at ideally less than 6-monthly intervals needs to be combined with other nutrition and health interventions.

The use and interpretation of serum retinol distributions in evaluating the public health impact of vitamin A programmes

“…Scale up of VA supplementation in Yemen was linked with a significant reduction in case fatality among children hospitalized with severe dehydrating diarrhoea (55) . Data from survey and surveillance based evaluations in Bangladesh have attested to an effectiveness of VA supplementation programmes in preventing xerophthalmia (56,57) . In summary, twice-yearly supplementation programmes can expect to reduce mortality and xerophthalmia in VAdeficient populations which suffer from major childhood infectious diseases including diarrhoea, measles, likely malaria and other severe febrile illnesses.…”

Diagnosis of night blindness and serum vitamin A level: a population-based study

“…Application of these specialized methodologies in population-based surveys has, however, been limited because they require expensive instrumentation and there is a lack of trained personnel. Therefore, most field assessments of childhood night blindness have relied on parents' reports of the condition (8)(9)(10)(11)(12)(13). However, the validity of this method for assessing the true level of night blindness has recently been the subject of discussion (14,15).…”

Vitamin A Deficiency

“…Where national surveys or surveillance data exist [199][200][201], it is clear that regions with a high prevalence of xerophthalmia share common dietary and other ecologic exposures (e.g., poverty, high levels of infectious diseases, poor development and health infrastructures, and strong seasonal fluctuation in food availability). Clustering of risk appears to intensify within smaller, disadvantaged groupings.…”

“…Low household SES is typically associated with xerophthalmia in young children, reflected by less parental education [195,199,207,223,227,[236][237][238][239][240][241] and landholding [195,199,207,236,242], poorer housing quality [195,207,223] and hygiene [195,207,240], fewer small assets [207,236,237,239] and draft animals [204,236,239] owned, and a more frequent history of child mortality in the family [195,207,223]. Not surprisingly, women with night blindness also come from socioeconomically disadvantaged families, exhibiting a poor diet, less asset ownership, and increased risks of anemia and [213], Nepal [215], Yemen [212], and Indonesia [216].…”

“…Supplement distribution may be combined with other national or regional community programs (such as a NID) or stand alone as a "vertical" activity, sweeping through communities in high-risk regions to dose children of the target age (6 months to 4 or 5 years) on a planned timetable, usually every 4 to 6 months [349,352,369]. Historically poor coverage rates, typically under 50% [199,221,349,350], have been vastly improved to 80% or more in recent years through campaign approaches that focus all distribution activities on two set days, 6 months apart, each year [370].…”