A Planet of Viruses - Carl Zimmer [13]
As scientists got to know phages better, it became clear that the debate between Herelle and Bordet was just a case of apples and oranges. Phages do not belong to a single species, and different phage species behave differently toward their hosts. Herelle had found a vicious form, called a lytic phage, which kills its host as it multiplies. Bordet had found a more benevolent kind of virus, which came to be known as a temperate phage. Temperate phages treat bacteria much like human papillomaviruses treat our skin cells. When a temperate phage infects its host microbe, its host does not burst open with new phages. Instead, the temperate phage’s genes are joined into the host’s own DNA, and the host continues to grow and divide. It is as if the virus and its host become one.
Once in a while, however, the DNA of the temperate phage awakens. It commandeers the cell to make new phages, which burst out of the cell and invade new ones. And once a temperate phage is incorporated into a microbe, the host becomes immune from any further invasion. That’s why Bordet couldn’t kill his first batch of E. coli with the phage—it was already infected, and thus protected.
Herelle did not wait for the debate over phages to end before he began to use them to cure his patients. During World War I, he observed that as soldiers recovered from dysentery and other diseases, the levels of phages in their stool climbed. Herelle concluded that the phages were actually killing the bacteria. Perhaps, if he gave his patients extra phages, he could eliminate diseases even faster.
Before he could test this hypothesis, Herelle first needed to be sure phages were safe. So he swallowed some to see if they made him sick. He found that he could ingest phages, as he later wrote, “without detecting the slightest malaise.” Herelle injected phages into his skin, again with no ill effects. Confident that phages were safe, Herelle began to give them to sick patients. He reported that they helped people recover from dysentery and cholera. When four passengers on a French ship in the Suez Canal came down with bubonic plague, Herelle gave them phages. All four victims recovered.
Herelle’s cures made him even more famous than before. The American writer Sinclair Lewis made Herelle’s radical research the basis of his 1925 best-selling novel Arrowsmith, which Hollywood turned into a movie in 1931. Meanwhile, Herelle developed phage-based drugs sold by the company that’s now known as L’Oreal. People used his phages to treat skin wounds and to cure intestinal infections.
But by 1940, the phage craze had come to end. The idea of using live viruses as medicine had made many doctors uneasy. When antibiotics were discovered in the 1930s, those doctors responded far more enthusiastically, because antibiotics were not alive; they were just artificial chemicals and proteins produced by fungi and bacteria. Antibiotics were also staggeringly effective, often clearing infections in a few days. Pharmaceutical companies abandoned Herelle’s phages and began to churn out antibiotics. With the success of antibiotics, investigating phage therapy seemed hardly worth the effort.
Yet Herelle’s dream did not vanish entirely when he died in 1949. On a trip to the Soviet Union in the 1920s, he had met scientists who wanted to set up an entire institute for research on phage therapy. In 1923 he helped Soviet researchers establish the Eliava Institute of Bacteriophage, Microbiology, and Virology in Tbilisi, which is now the capital of the Republic of Georgia. At its peak, the institute employed 1,200 people to produce tons of phages a year. During World War II, the Soviet Union shipped phage powders and pills to the front lines, where they were dispensed to infected soldiers.
In 1963, the Eliava Institute ran the largest trial ever conducted to see how well phages actually