Immunologists study the processes and substances associated with the resistance of human beings and animals to infections and diseases. They study immune reactions and try to work out ways to boost the immune system to enable it to resist harmful micro-organisms more efficiently.

The task of the human immune system is to protect the body against viruses, bacteria and other disease-causing agents such as influenza, meningitis and AIDS. However, due to a number of factors, people are not always resistant to specific strains of micro-organisms which cause disease and infection.

Immunology is the study of our protection from foreign molecules or invading organisms and our responses to them. These invaders include viruses, bacteria, protozoa or even larger parasites. In addition, we develop immune responses against our own proteins in auto-immunity.

Human beings have two lines of defence against foreign organisms: outer barrier tissues and the inner adaptive immune system. The barrier tissues, such as the skin, stop the entry of organisms into our bodies. If these barrier layers are penetrated, through a bite, for example, the body contains cells that respond rapidly to the presence of the invader. However, the adaptive immune system may take days to respond to a primary invasion. The body produces antibodies (proteins that bind to foreign antigens) in which specific cells recognise foreign pathogens and destroy them. If neither of these immune defence mechanisms function properly in the person or animal, then alternative remedial approaches must be taken. Usually this is in the form of antibiotics or another form of sophisticated, strong medical treatment.

Immunologists help scientists and physicians in the diagnosis, prevention and treatment of infections in animals and people by investigating how organisms cause disease and their role in attacking the immune system. Work in immunology is often interdisciplinary, so they may work closely with chemists, biochemists, geneticists, genetic engineers, pathologists and other physicians, environmentalists, civil engineers, veterinarians and geologists.

Immunologists use a variety of specialised equipment such as gas chromatographs and high pressure liquid chromatographs, electrophoresis units, thermocyclers, fluorescence activated cell sorters and phosphoimagers. They may also use computers in conducting experiments. It is common to find an immunologist using a microscope or performing experiments in a laboratory. However, the nature of the work may vary considerably with each assignment.


  • universities and colleges

  • research organisations

  • hospitals, clinics and other health care facilities

  • private practice or in group practice

Getting Started

  • speak to an immunologist about this career

  • read up on diseases of the immune system

  • try and do voluntary work for organisations involved with people with immunological diseases


Masinde Muliro University of Science and Technology, Multimedia University of Kenya, University of Johannesburg, University of Pretoria, University of Stellenbosch

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