Prevention of Childhood Blindness (WHO, 1992, 48 pages): 3. Strategies for prevention

Prevention of Childhood Blindness (WHO, 1992, 48 pages)

		(introductory text...)
		Acknowledgments
		Preface
		Introduction
		1. Prevalence and epidemiology of childhood blindness
		2. Causes of childhood blindness and current control measures
		3. Strategies for prevention
		4. Major areas of action
		5. Intersectoral collaboration and the role of nongovernmental organizations
		6. Priority areas for future action
		References
		Glossary
		Annex 1
		Annex 2

3. Strategies for prevention

A variety of strategies have been developed against the major causes of childhood blindness and the resulting visual loss. It is significant that many of the strategies are directed towards public health measures, rather than eye care itself, because of the many complex factors determining the occurrence and severity of most blinding disorders.

Strategies to prevent childhood blindness should address the possibility of intervention at all three prevention levels:

- Primary prevention—prevention of the occurrence of a disease in a population.
- Secondary prevention—prevention of sight-threatening complications and visual loss once the disease has appeared.
- Tertiary prevention—minimization of the visual disability resulting from previous disease or injury.

The main strategies for preventing blinding diseases in children are described below.

Prophylaxis is the systematic use of a procedure or medication for primary prevention of a disorder. One of the most well-known examples in relation to childhood blindness is the use of the Crede method (application of 1% silver nitrate solution) to protect newborn infants against conjunctivitis due to N. gonorrhoeae.

Immunization is another primary preventive strategy, which can be used against infectious diseases with blinding sequelae, i.e., measles and rubella.

Appropriate antenatal care is a useful strategy for the primary prevention of conjunctivitis in the newborn, since pregnant women can be screened for N. gonorrhoeae. It is also of general value in detecting risk factors such as pre-eclampsia and multiple pregnancy, which may lead to low birth weight, prematurity and perinatal asphyxia. Fetal monitoring and appropriate timing and method of delivery may reduce this last complication.

Neonatal care is the provision of proper care for the newborn baby, such as maintenance of normal body temperature, administration of vitamin K, clearing of the airway and application of the Crede prophylaxis.

Improvement of nutrition is a valuable strategy for the prevention of a variety of disorders. In relation to blinding diseases in children, it refers to a regular intake of vitamin A, which may be achieved through better use of local sources and possibly through the fortification of certain food items or dietary supplementation with vitamin A capsules.

Education as a preventive strategy may include public education through the mass media, to increase general awareness about blinding diseases and their prevention in children, or more specific health education about locally endemic diseases or aimed at particular risk groups or target audiences. Examples include public education about measles to improve immunization coverage, or specific education for mothers about weaning foods or the possible dangers of traditional practices. Another recent example is the introduction of social marketing methods to promote better nutrition.

Genetic counselling is a primary preventive strategy against genetic disorders. It is being increasingly considered in many countries, but has so far not been implemented on a large scale in view of the resources needed and the complex social and cultural issues involved.

Legislation is a primary strategy for the prevention of some causes of childhood blindness. The best-known example is legislation on the application of the Crede prophylaxis in many countries, but other examples include restrictions on the sale of fireworks, standards for the safety of spectacle lenses, domestic products and toys, and laws governing the use of seat-belts in cars.

Early recognition and treatment of potentially blinding disease are important for secondary prevention of childhood blindness. This may be important in a number of conditions, such as conjunctivitis in the newborn, xerophthalmia, congenital cataract, congenital glaucoma and ocular injuries. This strategy may also include the tertiary prevention of blindness in children through surgery for conditions such as congenital cataract. In the case of children, early surgical treatment is generally indicated because of the risk of amblyopia.

Improved hygiene and care, particularly during illnesses may reduce both the incidence and the severity of some blinding disorders. Examples include good hydration and topical treatment of secondary eye infections for children with measles, cleanliness during epidemics of conjunctivitis, and oral rehydration of children with diarrhoea.

Finally, improving the socioeconomic development of a community can be seen as a preventive strategy for a variety of conditions and diseases.

The above list does not reflect any order of priority, which will obviously vary according to the local situation. Tables 3-5 set out in summary form the management of the various causes of blindness in children from the perspective of primary, secondary and tertiary prevention, together with an outline of the needed human resources, training and infrastructure. The referenced texts should be consulted for more detailed information.

Table 3. Prevention of prenatal causes of childhood blindness

Primary	Secondary	Tertiary	Human resources/training	Facilities/ supplies
Congenital cataract and congenital glaucoma of genetic origin
Genetic counseling Avoidance of consanguineous marriage for autosomal recessive disorders	Early diagnosis Early surgical treatment Visual rehabilitation	Low-vision care for those with poor visual outcome	Recognition by health worker Specialist care (ophthalmic genetics) desirable	Tertiary surgical/anaesthetic facilities
Congenital cataract of infective origin (rubella)
Rubella immunization as indicated	Early diagnosis Early surgical treatment	Low-vision care, rehabilitation for those with resulting multiple handicaps	Training in pediatric ophthalmology	Rubella vaccine Tertiary surgical/ anaesthetic facilities
Retinoblastoma
Genetic counselling Targeting of high-risk groups	Early detection Early treatment (radiotherapy or surgery)	Rehabilitation in cases of bilateral enucleation	Specialist care (ophthalmic genetics, oncology) desirable	Access to specialized centres including radiotherapy
Other prenatally determined conditions
Education regarding use of drugs, smoking, alcohol in pregnancy	Early detection of abnormalities especially in high-risk babies. Proper management of visual impairment	Low-vision care for optimal use of residual vision	Training in pediatric ophthalmology	Tertiary facilities for diagnosis and management

Table 4. Prevention of neonatal causes of childhood blindness

Primary	Secondary	Tertiary	Human resources/training	Facilities/ supplies
Ophthalmia neonatorum
Antenatal care: Recognition and treatment of maternal infection Immediate neonatal care: Cleansing of lid margins and application of prophylactic medication: - tetracycline 1% eye ointment or - silver nitrate 1% eye drops	Early diagnosis and treatment or referral Ceftriaxone, 50 mg/kg of body weight (maximum dose125 mg)' intramuscularly, as a single dose If this is not available: kanamycin 25 mg/kg body weight (maximum dose 75 mg) intramuscularly as a single dose, plus tetracycline 1% eye ointment every hour for 1 day, then every 3 hours for 3 days, then 4 times a day for at least 10 days	Surgical treatment for corneal opacification (keratoplasty or optical iridectomy)	Training of midwives and traditional birth at fondants in: - prophylaxis - treatment	Supplies of: - tetracycline 1% eye ointment or - silver nitrate 1% eye drops - appropriate antibiotic for systemic treatment, considering possibility of penicillin resistant strains of N. gonorrhoeae
Retinopathy of prematurity (ROP)
Antenatal care: Measures to prevent low birth weight/ premature birth Neonatal care: Monitoring of oxygen therapy Monitoring of arterial oxygen tension	Identification of stage 3 ROP² If oxygen treatment given without monitoring: - screen all babies<2000 g, <36 weeks If oxygen treatment monitored: - screen all babies<1500 g, <32 weeks If stage 3 ROP found: - treat with cryotherapy	Surveillance and treatment of glaucoma, retinal detachment, myopia Low-vision services	Ophthalmologists with specialized training in pediatric ophthalmology	Oxygen monitoring Funduscopy Cryotherapy
Birth asphyxia
Improved obstetric care	Early identification of visual disturbance in anoxic infants	Low-vision services	Training in obstetric care for personnel concerned	As needed for adequate obstetric care

Table 5. Prevention of childhood causes of blindness

Primary	Secondary	Tertiary	Human resources/training	Facilities/supplies
Vitamin A deficiency
Increase maternal vitamin A supply, encourage breast-feeding and proper weaning Prevent and control childhood diseases and conditions-meas- les, diarrhoeal diseases, acute respiratory infection, protein energy malnutrition Nutrition education Vitamin A supplements	Identity and treat signs and symptoms of vitamin A deficiency¹ - for children over one year: immediately on diagnosis 200000 IU of vitamin A orally; repeat same dose the next day and 4 weeks later - for children under one year and all children weighing less than 8 kg: treat with half the above dose	Optical iridectomy, keratoplasty in a few cases Low-vision services	Trained primary health care workers Trained personnel in health-related sectors	Vitamin A supplies(for supplements) Educational material
Measles
Promote and provide measles immunization with high coverage	Vitamin A (200000 IU) and topical antibiotic for all children with measles If cornea affected, treat with vitamin A as above, and topical antibiotics	Optical iridectomy, keratoplasty in a few cases Low-vision services	Training of primary health care workers in recognition and management of affected children	Cold chain/vaccines Vitamin A supplies Ocular tetracycline (1%) Educational material
Harmful eye practices
Health education, community awareness Easily accessible primary eye care facilities and drugs	Appropriate treatment of ocular complications in eye care facilities	Optical iridectomy, keratoplasty in a few cases Low-vision services	Training of primary health care workers Training of traditional practitioners in primary eye care	Primary eye care services Supply of essential eye drugs, especially topical antibiotics
Herpesviral keratitis
Control risk factors, e.g., vitamin A deficiency, measles, malaria	Early diagnosis and referral for antiviral therapy	Optical iridectomy, keratoplasty in a few cases Low-vision services	Training of primary health care workers in primary eye care	Antiviral drugs, e.g., idoxuridine
Trachoma
Improved community and individual by- giene, including regular face-washing Health education	Mass treatment with topical tetracycline in trachoma-endemic areas Systemic antibiotic treatment of selected severe cases of trachoma, e.g., those not responding to topical treatment Surgical correction of trichiasis/entropion(uncommon in child hood)	Optical iridectomy, keratoplasty in a few cases Low-vision services	Training of primary health care workers in primary eye care Training in trichiasis surgery	Supply of tetracycline 1% eye ointment Supplies and equipment for trichiasis surgery Clean water
Ocular trauma
Accidental injury Legislative measures, e.g., regarding seat- belts, fireworks, etc. Public education Non-accidental injury(battered child syndrome) Identify high-risk groups Counselling	Early recognition and primary treatment Speedy referral for definitive treatment Adequate care and repair of injuries Avoidance of harmful eye practices Ophthalmic examination as part of multidisciplinary assessment	Specialized surgical intervention, e.g., repair of retinal detachment, keratoplasty Surveillance for late complications Low-vision care	Training of primary health care workers in primary eye care Ophthalmic surgery Social workers for counselling	Preferably tertiary surgical facilities Facilities for complete eye examination, including general an aesthesia