The written history of pneumonia begins with the Greek Hippocrates, who lived in the fourth century B.C. However, he described it as an ancient disease. Maimonides, a philosopher and physician who was born in the 12th century in Cordoba, knew about pneumonia, too. He described it in terms that might have used by a modern doctor: "acute fever, sticking pain in the side, short rapid breaths, serrated pulse and cough."
Before and after Maimonides, pneumonia was a scourge. People who lived close together, such as prisoners, cloistered monks or nuns, boarding school pupils or even residents of close-knit communities or dense slums, often suffered epidemics of the disease. Victims died gasping for breath, helpless against the disease.
No one understood what caused pneumonia. It was Edwin Klebs, in 1875, who first observed bacteria from the airways of people who had died of one form of pneumonia. A species of pneumonia-causing bacteria was named after him, and various species of bacteria became known to cause pneumonia. Still, pneumonia was the most common cause of death in 1900.
Now, doctors treat bacterial pneumonia, the most common type of pneumonia, with antibiotics. The first antibiotic used to treat pneumonia was penicillin. Sir Alexander Fleming discovered it by accident in 1929, when he brilliantly observed that a colony of bacteria was unable to grow where penicillium mold had contaminated its environment.
Viruses cause pneumonia, as well. Viral pneumonias are not treated with antibiotics because they would be ineffective. However, these pneumonias can sometimes be treated with antivirals. The first antiviral drugs were discovered in the 1960s using laborious trial-and-error methods. Scientists would grow a culture of virus and then attack it with a variety of substances until one worked.
By the 1980s, though, viral genes were being sequenced. Researchers had a clearer idea of how viruses worked and could target the vulnerable points in a particular target virus. Now, patients with viral pneumonia can sometimes be treated with medicines including ribavirin, amantadine, rimantadine or acyclovir, depending on their specific circumstances. Most viral pneumonias are relatively mild, but in serious cases antivirals can save lives.
Public health has also progressed in the centuries since Rabbi Maimonides. Modern sanitation keeps pneumonia-causing germs out of food and water. Vaccinations prevent pneumonias caused by certain microbes. Many people with pneumonia recover quickly, often with no after-effects.
Still, problems remain. Some bacteria are now resistant to antibiotics. Some diseases, such as HIV, make their victims vulnerable to dangerous pneumonias that were once rare. Drug addicts and alcoholics still die of aspirant pneumonia, a disease that strikes people who already have enough problems. Although society has made great progress, the battle against pneumonia is not yet over.