Prevalence and causes of blindness in children in Vietnam.
OBJECTIVE
To estimate the prevalence of blindness in children in Vietnam and to assess the major causes.


METHODS
A population-based study sampled children from 16 provinces across Vietnam. The second study examined children attending all blind schools in Vietnam.


METHODS
In 16 provinces, 28 800 children aged 0-15 were sampled. In 28 blind schools, 569 children aged 0-15 were examined.


METHODS
In children not seeing well according to the parents, presenting visual acuity (PVA) was assessed. If PVA was <3/60 in one or both eyes, the child was examined by an ophthalmologist. All children in blind schools were examined by a pediatric ophthalmologist.


METHODS
Blindness was defined as PVA <3/60 in the better eye. Causes of visual loss were classified using the World Health Organization classification.


RESULTS
In the population-based study, 22 children had a PVA <3/60 in the better eye, a prevalence of 7.6/10 000 children (95% confidence interval [CI], 4.9-11.8/10 000). Fourteen children had a pinhole visual acuity <3/60 in the better eye, a prevalence of 4.9/10 000 (95% CI, 2.8-8.4/10 000). An estimated 16 400 (95% CI, 10 500-25 300), children were blind from all causes, with 36.4% from uncorrected refractive errors. In the blind schools, 411 children had a PVA <3/60 in the better eye and 55.5% were male. Conditions of the retina (24.6%) and cornea (24.0%) predominated. Retinopathy of prematurity (ROP) caused blindness in 32.6% of children younger than 10 years, but in only 6% of older children. The converse was true for corneal scarring and phthisis (14.0% and 27.3%, respectively). All other causes were similar between age groups (53.5% and 66.7%, respectively). More than half of all causes were avoidable.


CONCLUSIONS
Vietnam is developing very rapidly, and this is impacting health indices. The mortality rate of those younger than 5 years declined from 65/100 live births in 1980 to 14/100 in 2008. The findings of this study show these changes, because the childhood blindness prevalence was relatively low, and the causes show improved control of measles and vitamin A deficiency, as well as increased services for premature babies. Eye care services for children should now focus on refractive errors, cataract, and control of ROP.
International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, United Kingdom. hlimburg@quicknet.nl
Hans
H
Limburg
Clare
C
Gilbert
Do Nhu
DN
Hon
Nguyen Chi
NC
Dung
Tran Huy
TH
Hoang
D000293:Adolescent; D017677:Age Distribution; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D017678:Sex Distribution; D014744:Vietnam / Q000453:epidemiology; D015354:Vision, Low / Q000453:epidemiology* / Q000209:etiology; D014792:Visual Acuity / Q000502:physiology; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data