Prevalence Of Night Blindness Research Articles

Determinants of night blindness in Bangladesh.

A cross-sectional study was conducted to evaluate the effect of a community-based health education intervention programme and to study the determinants of night blindness in Bangladesh. The intervention programme was implemented to reduce the morbidity of nutritional blindness (night blindness) in the northern part of Bangladesh (Ranjpure district) during 1986-1989. A baseline study in 1986 covered 2010 households with a total population of 11,600, and the evaluation study in 1989 covered 2011 households with a total population of 10,456. Prevalence of night blindness was studied among children aged < 9 years in these households. The prevalence of night blindness per 1000 children was reduced significantly during the intervention period from 50.7 in 1986 to 26.7 in 1989. However, the post-intervention prevalence varied significantly between areas. Multivariate analyses showed that consumption of fish, meat, milk or eggs, dark green leaf vegetables, yellow fruits and vitamin A capsules were significant predictors of night blindness. In addition, family income, mother's literacy, family size and area of residence exhibited strong and statistically significant associations with night blindness in the 1989 cross-sectional study. The prevalence of night blindness was highest among 4-6 year old girls and 7-8 year old boys. The sex difference was, however, not statistically significant.

A prevalence study of vitamin A deficiency and xerophthalmia in northeastern Thailand.

An epidemiologic survey of the prevalence of xerophthalmia and vitamin A deficiency was conducted in May and June 1985 in a multistage random sample of 1,772 children 1-8 years of age from 16 rural villages and the capital city of the Sakon Nakhon province in northeastern Thailand. Data of clinical eye examinations were available for 92% (n = 903) of the eligible children aged 1-5 years (n = 982); history of night blindness was obtained from a reliable source from 93% (n = 1,644) of the whole sample; and biochemical data were available for 60% (1,060) of the children examined. The distribution of clinical signs of xerophthalmia and serum retinol levels differed between the rural and urban areas. In the urban area, no signs of xerophthalmia or deficient serum retinol levels were found in the preschool children examined. The prevalence of night blindness in the rural area was 1.3% in children aged 1-5 years (95% confidence interval (Cl) 0.7-1.9); Bitot's spots were seen in 0.4% (95% Cl 0.1-1.0); 12.7% (95% Cl 9.9-15.5) showed deficient serum retinol levels (less than 0.35 mumol/liter). Of the children aged 1-8 years, 9.6% (95% Cl 7.8-11.4) showed deficient serum retinol levels. In the rural area, the prevalence of night blindness, Bitot's spots, and deficient serum retinol levels indicates a problem of public health importance according to World Health Organization criteria.

The prevalence and distribution of xerophthalmia in pre-school age children of the Luapula Valley, Zambia.

Four thousand two hundred and seventy-five children aged less than 6 years were examined for signs of xerophthalmia in a population based cross-sectional study in the Luapula Valley of Zambia. The overall prevalence of xerophthalmia was 1.89 per cent. The prevalence of nightblindness (XN), Bitot's spots (X1B), severe corneal lesions (X3A, X3B), and corneal scars (XS) were 1.26, 0.44, 0.02, and 0.68 per cent, respectively. One child was totally blind and four children had unilateral blindness. Comparison is made with data from other parts of Africa. It is concluded that xerophthalmia is a public health problem in this valley and a major cause of blindness in childhood.

Distribution of xerophthalmia among children in the traditional quranic schools in Al-Gezira State of Sudan

Background: Vitamin A deficiency is considered a serious public health issue in poor nations, which leads to corneal opacity and results in childhood blindness in most of the low-income countries. Aim: To determine the prevalence of xerophthalmia among children at traditional Quranic schools in Al-Gezira state of Sudan. Materials and Methods: This was a quantitative cross-sectional study conducted on 822 children aged from 5 to 15 years, living in traditional Quranic schools. The clinical examinations for all children in this study include the demographics of patients (name, gender, age, and duration of students in schools), symptoms (vision during the day and night), and then outer eye checked for all children by lope and magnifier and visual acuity using Snellen's chart. Results: The prevalence of night blindness, conjunctival xerosis, corneal xerosis, and Bitot's spots was 17.3%, 20.3%, 0.2%, and 0.7%, respectively. There was a significant association between the duration of staying the children at the schools and the development of night blindness (P ≤ 0.02). Conclusion: Children of this community are susceptible to xerophthalmia because food is inadequate of Vitamin A. The governmental and nongovernmental organization should supply this community by the diet rich of Vitamin A and Vitamin A supplementation orally for affected children as well as annually comprehensive eye examinations.