Cause of blindness/ visual impairment

Immediate cause / risk factors

Role of community in prevention/minimisation of impairment

Examples of environmental, policy and socio-cultural influences

Cataract

Associated with ageing but other possible causal factors e.g. smoking and dehydration

Willingness of people to have cataract surgery

• Beliefs concerning benefits of cataract surgery, side effects
• Quantity and quality of cataract surgery available
• Importance attached by decision-makers to provision of cataract surgery
• General attitudes of community to elderly

Glaucoma

Intraocular pressure and  damage to the optic nerve

Seeking eye health care (so that any glaucoma can be identified at an early stage when condition is treatable)

• Awareness of early symptoms of vision loss and importance of seeking prompt treatment from trained health worker.
• Training of front-line health workers in detection and referral of glaucomas at early stage
• Availability of specialist treaatment facilities

Trauma

Injuries resulting in damage to the eye

Actions designed to reduce risk of injuries in home, community and workplace settings - including both accident avoidance behaviours and promotion of safe environments for play and work.  

• Availability of safe environment/working conditions/enforcement of safety regulations
• Community perception of risk/seriousness  of blinding injuries
• Safety legislation e.g. onseat belt wearling, traffic accident prevention, community and occupational hazards

Night blindness and Xerophthalmia

Vitamin A deficiency

Consumption of Vitamin A rich foods e.g. green leafy vegetables or vitamin A supplementation

Consumption of fortified foods where available

• Beliefs concerning consumption of green leafy vegetables/other vitamin A rich food
• Influences on cultivation/kitchen gardening
• Availability of land and irrigation
• Policies on food fortification

Onchocerciasis (river blindness)

Infection with nematodes whose offspring microfilaria can travel through tissue including the eye. It is transmitted by the blackfly (Simulium)

Control of fly breeding

Uptake/compliance with treatment with ivermectin

• Beliefs concerning onchocerciasis and its treatment, the side effects of treatment, the role of worms causing blindness, willingess to pay for treatment
• Economics and settlement patterns
• Availability/affordability of ivermectin

Trachoma

Infection of eye with Chlamydia trachomatis by contact with infective materials from eye of an infected persons

Cleanliness of face

Fly control through disposal of faeces in latrines

Uptake of treatment/surgery

• Beliefs about sanitation, water use, hygiene including facewashing, flye control and eye care/treatment
• Community decision-making on hygiene
• Cultural, economic and social barriers to provision and access to water and sanitation
• Quantity and quality of facilities for treatment of trachoma

Diabetic retinopathy

Caused by diabetes mellitus

Persons with symptoms of diabetes seeking health care/eye screening

Lifestyle modifications for prevention of non-insulin dependent diabetes

• Availability of screening services and treatment facilities
• Community understandings of diabetes and its prevention/associate risk of blindness
• Training of helath workers in management of blinidng complications of diabetes

Refractive errors

May be genetic and also associated with ageing.

Support for community-based screening programmes

Self-referral of persons with vision problems.

• Beliefs of parents, teachers and decision-makers of the importance of early detection of refractive errors
• Knowledge/skills of teachers/parents/health care workers in detection of uncorrected refractive errors
• Availability of spectacles/optical services

Leprosy

Infection by leprosy bacillus. Route of infection/primary prevention uncertain

Early presentation of leprosy cases for treatment

Compliance with treatment regimes

• Awareness of early symptoms of leprosy, the risks attached to delaying treatment and that leprosy is treatable.
• Stigma attached to diagnosis of leprosy

Other infectious diseases

Conjunctival infections

Transmission to baby of sexually tranmitted infections (Ophthalmia neonatorum)

Complications of AIDS/HIV

Appropriate self-care and early self-referral to health facilities

Health care workers treating babies after delivery  e.g with tetracycline.

Women coming early for treatment of STDs

Adoption of safer sexual practices including use of condom

• Awareness/skills of health care workers/TBAs of the risks of blindness from STDs and the importance of treatment of babies after delivery e.g. with tetracycline
• Community beliefs on prevention  and treatment of  AIDS/STDs
• Availability of condoms
• Quality and quantity of national programmes for AIDS, STDs and reproductive health

Congenital blindness

Genetic influences

Uptake of genetic counselling

• Availability of  Genetic counselling services