Vaccination against virus diseases.

One of the most important and most lasting benefits of medicine to human health and health expenditure is the controlled immunological interruption of the vicious cycle of infectious disease such as smallpox, poliomyelitis, yellow fever, measles. Smallpox, with globally more than 2.5 million cases ten years ago, is gone. The incidence of infectious diseases with available immunoprophylaxis has been reduced by 90 % over the past two decades, while the incidence of diseases without vaccine has nearly tripled. By contrast, influenza, a disease against which there have been vaccines in existence for many years, demands more deaths than any other infectious disease. Reasons for this failure of influenza immunoprophylaxis are discussed and suggested to include: indiscriminate use of available vaccines of which some types are much less antigenic than others, the disappointment that influenza virus vaccines will not protect against influenza-like illnesses caused by noninfluenza virus pathogens and the concomitant indiscriminate rejection of all influenza vaccines as being of doubtful value; superficial vaccination policies which aim at narrow populations, leaving those most likely to spread the virus the full potential to do so; the unjustified fear of side reactions following vaccination which are considerably less severe than the disease this vaccination is attempting to prevent.