Childhood Blindness - A Global Tragedy
Blindness is defined by the WHO as a corrected visual acuity of less than 3/60 is the better eye which is approximately equal to an ability to count fingers of 3 meters or a central visual field of 100 from the point of fixation.
A CHILD is defined by UNICEF as an individual aged 0-15 years of age. This age group constitute 40% of the population.
Globally there are estimated to be 45 million blind people of which 1.4 million are children and 5,00000 children become blind every year. Half of the Worlds blind children live in South East Asia region. In every one minute, a child becomes blind in this world. It has also been suggested that 50 to 60% of blind children die within short period of becoming blind. 80% of childhood blindness occurs before the 5th birth day. 0-5 years are the most valuable age group.
Causes of Blindness
Common causes of childhood blindness are:
- Corneal disease such as corneal scar due to vitamin A deficiency, measles, use of harmful traditional eye remedies, ophthalmic neonatarum, corneal ulcer, staphyloma, pthisis bulbi, corneal dystrophy etc.
- Ocular injury.
- Congenital or developmental cataract.
- Retinal diseases such as pathological myopia, retinitis pigmentosa, retinal dystrophy, retinopathy of prematurity, retinoblastoma etc.
- Congenital anomalies such as microphthalms anophthalmos, coloboma, albinism.
- Congenital glaucoma.
- Refractive error.
- Optic nerve disease.
- Cortical blindness
- Uncorrected Aphakia
The major causes of childhood blindness vary widely from country to country, being largely determined by socioeconomic development and the availability of primary health care and eye care services. In poorer regions of the world corneal scarring due to vitamin A deficiency, measles, ophthalmic neonatarum and the use of harmful traditional eye remedies predominate. In affluent countries lesions of the optic nerve and higher visual pathways, due to a variety of causes (e.g. prematurely, metabolic diseases) predominate. In middle income countries the picture is mixed, with retinopathy of prematurely becoming an important cause. In all regions retinal conditions (mainly dystrophies) are important, as well as cataract and congenital abnormalities.
Avoidable Causes of Childhood Blindness:
It is estimated that in almost half of the children who are blind today, the underlying cause could have been prevented or the eye condition could be treated to preserve vision or restore sight. Preventable causes of blindness in children include all causes of corneal scarring, infectious causes and retinopathy of prematurely. In theory some forms of genetic diseases are potentially preventable through genetic risk counseling, but in proactive this is often difficult to achieve. Treatable causes of childhood blindness include cataract, glaucoma, and stage 3 threshold retinopathy of prematurely. Overall almost half of the world's blind children are blind from avoidable causes. In developing countries the proportion of blindness that is avoidable is significantly higher than in industrialized countries.
Corneal scarring is the single most important cause of avoidable blindness, followed by childhood cataract. Control of these conditions is given priority in WHO's vision 2020. The right to sight program, together with correction of significant refractive errors and provision of services for low vision.
VISION 2020 Targets for Control of Blindness in Children:
The VISION 2020 program has identified three broad components for strengthening eye care delivery:
Strategies, with targets, for the control of specific diseases where cost effective interventions already exist.
Human Resource Development
Infrastructure and appropriate technology.
Specific Disease Control Measures :
- Reduce the global prevalence of childhood blindness from 0.78/1,000 children to 0.4/1,000 children,
- Elimination of corneal scarring caused by vitamin A deficiency, measles, or ophthalmia neonatarum.
- Elimination of new cases of congenital rubella syndrome.
- All children with congenital cataract to receive appropriate surgery, with immediate and effective optical correction, in suitably equipped specialist centers.
- All babies at risk of retinopathy of prematurity to have fundus examination by trained observer 6-7 weeks after birth. Cryo or laser treatment to be provided for all those with treatable disease.
- All school children to receive a simple vision screening examination, and glasses should be provided for all those with significant refractive error. This should be integrated into the school health program.
Human Resources Development :
- Ensure that prevention of childhood blindness is an explicit aim of all primary health care programmes.
- Ensure that all secondary level eye clinics have facilities to provide appropriate spectacles for children with refractive errors.
- Train one refractionist per 100,000 population by 2010.
- Train at least one low vision worker for every 20 million children, by 2010 and for every 5 million by 2020.
- Train one pediatric-oriented ophthalmologist for every fifty million population by 2010, and one per 10 million population by 2020.
Appropriate Technology & Infrastructure Development :
- Development of low cost, high quality low vision devices, which should be widely available, even in low income countries.
- Establish a network of specialist "Childhood blindness" tertiary centers.
Childhood Blindness - A Tragic Consequence:
Majority of the childhood blind are the children of deprived community where poverty, illiteracy, malnutrition, poor hygiene, poor sanitation and the absence of modern ophthalmic services and resources are scarce to non existent. The cataract interventions are as cost effective as immunization and can have a very significant and rapid impact in reducing the burden of avoidable blindness.
The mass distribution of vit a capsule at 6 months intervals is one of the highest ranked priorities of all health interventions available. So, there is every reason to consider blindness prevention as one of the most worthwhile public health and developmental intervention that can be undertaken.
Another important aspect to consider is that many of the causes of blindness in children are also causes of child mortality such as vitamin A deficiency, measles, meningitis, rubella. The control of blindness in children is therefore related to child survival.
Blindness in children is a tragedy for the child and their family, and incurs considerable cost. It posses a major social and economic burden on community as well as individuals.
However, if the causal factors are identified and addressed timely, the incidence of blindness can be lowered to a significant extent.
Preventive activities need to be integrated not only into primary eye care but also into existing eye care services. It is important to remember that a blind child has many years of blindness ahead of them, and that restoring the sight to one blind child is equivalent in terms of "blind years" of restoring the sight to 8 people who are blind from age related cataract. Children, therefore, deserve our attention expertise and time.
Similar of Childhood Blindness - A Global Tragedy