The thought of birth defects caused by rubella, rows of iron lungs housing children crippled by polio, or the horrific sound of a baby struggling with whooping cough can still evoke dread among people who have seen firsthand the damage inflicted by these and other vaccine-preventable diseases. Fortunately, those scourges are virtually unknown to modern generations that have had access to vaccines all their lives.
For more than 200 years vaccines have proved to be one of the most successful, lifesaving and economical methods of preventing infectious disease, second only to the sanitization of water. Vaccines have spared millions of people from early death or crippling illnesses and made the global eradication of smallpox in 1979 possible. Health experts now pledge to eliminate polio, measles and perhaps one day even malaria—although, as we shall see, a malaria vaccine will require novel approaches to immunization to be successful.