2.3 Public health interventions
Surveillance and reporting are clearly essential to ensure coordinated action to protect public health, but the range of responses can be bewilderingly diverse. A useful way of thinking about direct public health interventions to control infectious disease is to distinguish between strategies that:
- use education to support behavioural changes that enable people to protect their own health or that of their children or other community members from infectious disease
- promote resistance to infection in the human host
- isolate a source of infection to prevent it from being passed on
- tackle an environmental source of infection.
For each of the categories 1 to 4, suggest one example of an intervention to control a specific infectious disease.
You may have chosen other examples, but here are some that illustrate the general principles.
- Education about hand washing with soap, particularly after defaecation and before handling food, is particularly effective at preventing diarrhoeal diseases (as you will read in Section 4.2.1).
- Vaccination with an inactivated preparation of influenza virus increases resistance to subsequent flu virus infection, provided the infective strain is the same as, or closely related to, a component of the vaccine (see the OpenLearn free course SK320_1 Influenza: A case study [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] for more information). Vaccination programmes against a range of infectious agents are estimated to save the lives of over 2.5 million people, mainly young children, every year.
- Quarantine of infectious individuals has been practised for centuries, for example, in the isolation hospitals and TB sanitariums of the late nineteenth and early twentieth centuries, and during outbreaks of swine flu, bird flu and SARS.
- The provision of insecticide-treated nets (ITNs) is a highly effective environmental strategy for controlling the insect vectors of pathogens such as malaria parasites (Figure 5). ITNs not only protect the individuals sleeping under the nets, but they also reduce the local mosquito population by contact with the insecticide.
©© WHO/TDR/CrumpFigure 5 Insecticide-treated mosquito nets erected over sleeping mats offer effective protection from the mosquitoes that transmit malarial parasites (Plasmodium species).
Aside from vaccination programmes, what other major public health strategies could have a similarly huge impact on the control of infectious diseases in populations?
Among the most important strategies are the provision of clean drinking water, adequate sanitation and the safe disposal of sewage and refuse – exactly the same goals that the nineteenth-century founders of the public health movement campaigned for as basic human rights. The provision of effective, accessible and affordable health services is also vital.
Less visible, but no less significant, contributions to population health come from:
- the provision of transport and other infrastructures to enable widespread access to health and social services
- controls on the pollution of the environment by traffic, agriculture and industrial processes
- an education system that delivers a high rate of literacy in the population, particularly in women, which is strongly associated with reduced morbidity and mortality rates among their children
- gender equality in access to the means of subsistence, goods and services, including health care
- an economic structure that supports an adequate income, shelter and nutrition for all households
- a stable and equitable political system.