Vaccination, more than any other form of medical intervention—more than antibiotics, or heart surgery, or any new drug—changed the face of human health. (A close contender might be safe childbirth.) Today there are vaccines against the deadliest of human pathogens: diphtheria, tetanus, mumps, measles, rubella. Vaccines have been devised to prevent infection by human papillomavirus (HPV), by far the major cause of cervical cancer. And we will soon encounter the triumphal discovery of not just one but several independent vaccines against SARS-COV2, the virus that released the Covid pandemic.
