2.2.1  Measures targeting the reservoir of infection

Diagnosis and treatment

First, you should be able to diagnose and treat cases of the disease, or refer the patient for treatment at a higher health facility. There are two ways to identify an infected individual: when a patient comes to you (Box 2.3, on the next page, describes how you should approach a patient in order to identify a case), and by screening (discussed below). Identifying and treating cases as early as possible, reduces the severity of the disease for the patient, avoiding progression to complications, disability and death; and it also reduces the risk of transmission to others.

Screening

Screening refers to the detection of an infection in an individual who does not show any signs or symptoms of the disease. It is carried out using specific tests called screening tests. Screening will help you to detect an infection early and organise appropriate treatment so as to reduce complications and prevent transmission to others. An example of screening that may be familiar to you is screening the blood of pregnant women for HIV infection.

Isolation

You will learn further details about tuberculosis in Study Sessions 13–17 of this Module.

Following detection of an infectious disease, you may need to separate patients from others to prevent transmission to healthy people. This is called isolation. It is not indicated for every infection, but it is important to isolate people with highly severe and easily transmitted diseases. For example, an adult case of active pulmonary tuberculosis (‘pulmonary’ means in the lungs) should be kept in isolation in the first two weeks of the intensive phase of treatment. The isolation period lasts until the risk of transmission from the infected person has reduced or stopped. The period and degree of isolation differs between different diseases, as you will learn in later study sessions.

Reporting

Cases of communicable diseases should be reported to a nearby health centre or woreda Health Office periodically, using the national surveillance guidelines.

Animal reservoirs

When infected animals are the reservoir involved in the transmission of communicable diseases, different measures can be undertaken against them. The type of action depends on the animal reservoir, and ranges from treatment to destroying the infected animal, depending on the usefulness of the animal and the availability of treatment. For example to prevent and control a rabies outbreak, the measures to be taken are usually to destroy all stray dogs in the area, and vaccinate pet dogs if the owner can afford this protection and the vaccine is available.