Vaccination is the most effective public health measure to prevent infectious diseases. Vaccines can greatly reduce the risk of infection by working with the bodys natural defences to safely develop immunity to disease. However, the immune system fights infection in many different ways, and in order to be effective, a vaccine must trigger the right type of immune response to recognize and destroy a specific virus, bacteria or parasite.
The majority of vaccines, such as those for polio and measles, stimulate a type of immune response called antibody-mediated immunity. But for some chronic infectious diseases such as tuberculosis and malaria, a different type of immune response, called cell-mediated immunity, is needed. Unfortunately, efforts to create a vaccine that prompt a cell-mediated immune response have had limited success….