Typhus, War, and Vaccines

March 16, 2016 Karie Youngdahl

U.S. Army medical personnel inoculate Egyptian civilians for typhus. Source: vaccines.mil
U.S. Army medical personnel inoculate Egyptian civilians for typhus. Source: vaccines.mil

Today's blog post is by Carley Roche, a recent graduate from Drexel University and an intern here at The College of Physicians of Philadelphia.

War is difficult on everyone, from the soldiers risking their lives to the civilians who get caught up in these violent affairs. While larger armies and more advanced weapons can aid in victory, an often overlooked variable in war chooses no allegiance: disease. One of the most devastating diseases throughout history during wartime has been typhus.

Typhus is a bacterial disease caused by Rickettsia bacteria. There are two types of the disease--endemic typhus and epidemic typhus. Rickettsia typhi causes endemic typhus, also known as murine typhus, and is the least virulent. Spread to humans by fleas on animals such as cats, opossums, raccoons, and rats, most notably from the Norway rat, victims of endemic typhus will experience a bodily rash, high fever, nausea, vomiting, discomfort, and diarrhea. Rickettsia prowazekii causes epidemic typhus, which is spread via lice. Symptoms are similar to endemic typhus; they are, however, much more severe and can include delirium, hypotension, and even death.

The first written recordings of typhus came in 1489 during the Spanish army’s siege of Granada. High fevers, rash-like symptoms covering the body, delirium, and gangrenous sores were reported. While 3,000 soldiers lost their lives to enemy action, nearly 17,000 lost their lives to what would later be known as typhus. In 1759 authorities estimated nearly 25% of English prisoners lost their lives to this disease, thus earning the name gaol or jail fever. A year later the term typhus began to be used for the disease, stemming from the Greek word typhos, meaning “smoky” or “hazy,” evoking the delirious state one can develop while infected. Typhus struck during war once again in 1812 during Napoleon’s retreat from Moscow. It is estimated that fewer than 100,000 French soldiers lost their lives to Russian soldiers, while as many as 300,000 French soldiers perished from typhus.

In the early 20th century, French bacteriologist Charles Nicolle observed typhus patients and noticed after receiving a hot bath and clean clothes they were no longer infectious. By 1909 he correctly hypothesized that the louse is the vector for transmitting the disease from person to person. Although he did not succeed in developing a vaccine against the disease, his discovery helped greatly on the Western Front during the First World War, when delousing stations were established. Unfortunately the Eastern Front did not have these stations, leading to the death of 10 to 40% of those infected. Nurses who treated the sick had an exceptionally high death rate from typhus. By the end of World War I epidemic typhus had reached its peak with more than 3 million people, mostly civilians, dying in Russia alone. Other Eastern European countries, such as Poland and Romania, lost several million citizens as well. With no vaccine, it seemed as if typhus would be one of the most deadly aspects of the gruesome World War.

During the inter-war period Rudolf Weigl, a Polish biologist and zoologist, began experimenting with lice in order to discover a typhus vaccine once and for all. He first used guinea pigs in his experiments, but by 1933 was able to use humans in large-scale testing. First he would grow healthy lice for about twelve days by having uninfected lice “feed” on humans once a day for about 30 to 45 minutes. Keeping the lice in small cages and strapping them to the thighs or calves of the human “feeders” allowed the lice to grow. Then he injected the lice with R. prowazekii in order to infect the lice with typhus. Next he would allow the lice to grow for an additional five days on human “feeders” who had been given the vaccine. Finally he would extract and grind up the lice’s midguts into a paste, which would become the vaccine. His method and vaccine was so successful that the few human testers who developed typhus, including Weigl himself, all quickly recovered from the disease. 

Because typhus had been a scourge for soldiers and civilians alike throughout history, the Nazi Party took a great deal of interest in Weigl’s work. They allowed his experimentations to continue at his own institute, the Weigl Institute in Lwów, Poland (now Lviv, Ukraine), in exchange for his vaccine to be sent to German soldiers on the Eastern Front. While Weigl technically did send a vaccine as asked, it was partially and intentionally weakened. He instead smuggled nearly 30,000 vaccine doses of his full-strength vaccine into the ghettos of Lwów and Warsaw. Weigl even secretly employed some Jewish people, Polish resistance fighters and key intellectuals, thus sparing the lives of countless people. Arthur Allen’s book The Fantastic Laboratory: How Two Brave Scientists Battled Typhus and Sabotaged the Nazis is a fascinating look at Weigl’s work.

Typhus is now considered to be endemic only in certain areas of the world, including Eastern Africa and a few areas in South and Central America. No vaccines are currently available to prevent typhus, but improved hygienic practices, effective insecticides, and antibiotics have made it easier to combat the disease and the lice that spread it. After centuries of war when typhus played a leading role in the casualties, the disease is finally retreating.