William Henry Harrison was 68 years old when he became the ninth president of the United States and the oldest US president until Ronald Reagan was elected nearly a century and a half later. He was sworn into office on 4 March 1841. Exactly one month later, he was dead. Since his death on this day 175 years ago, it has been taken for granted by even the most eminent presidential historians that an overly long inaugural address delivered in freezing weather without a hat, overcoat, or gloves led to a fatal case of pneumonia. Fatal pneumonia, however, is a diagnosis in several respects at odds with the detailed description of Harrison’s final illness left by his personal physician, Dr. Thomas Miller.

Although Harrison developed symptoms of pneumonia during the course of his final illness (i.e., fever, difficulty breathing, and cough productive of small amounts of blood-tinged sputum), they were intermittent rather than progressive and didn’t begin until 2 days after the onset of gastrointestinal complaints, which proved to be both relentless and progressive. Harrison’s initial complaints were constipation and abdominal distension, which persisted for 5 days in spite of repeated laxatives and enemas administered by Dr. Miller. On the sixth day of illness, Harrison’s bowels finally opened, producing a flood of “foetid,” watery diarrhea, a sinking pulse, cold blue extremities, and, ultimately, death. The character and course of the illness, including the pulmonary complaints, are typical of typhoid fever. Moreover, given the dominance of Harrison’s gastrointestinal complaints during the course of his fatal illness, it is more likely that he died of a gastrointestinal infection–specifically typhoid fever–with secondary involvement of his lungs than of a pulmonary infection (i.e., pneumonia) with secondary involvement of the intestine. ...