Preventing corneal blindness in the community involves action by the community itself, as well as actions by government and non-governmental organisations in the form of HEALTH and development services. In order to be effective, eye health workers need to understand how all of the above can work together.

• Primary prevention: Actions or interventions taken to prevent the onset of disease

• Secondary prevention: Actions taken to prevent complications and/or the development of visual disability due to an existing disease
• Tertiary prevention: After the immediate problem has been ADDRESSED by SURGERY or other treatment, actions to restore function or reduce existing disability from disease complications, i.e. corneal transplantation
• Right up to the point when someone is seen by an eye care WORKER or admitted to hospital, the community will influence what happens.

Consider ophthalmia neonatorum as an example. As an eye care worker, you may have little control over the following:

the risk factors and immediate medical CAUSES, e.g. parents' sexual behaviour and the presence of Neisseria gonorrhoea

the contributory and social factors, e.g. the lack of antibiotic drops in the labour ward, poverty associated with dangerous work, poor access to water and sanitation, or a community's preference for traditional medicines.

However, the community has the potential to influence most of these factors, either through change in the behaviour of individuals, or by lobbying for improvements at the community level.