The bacteria Salmonella enterica typhi is one of three species of the Salmonella genus; together these diseases are known as salmonelloses. Typhos in Greek means 'to smoke' or 'cloud' or 'vapor.' Typhoid fever was thought to have been transmitted through a cloud of sickness known as miasma. The Salmonella typhi bacteria are an obligate parasite with no other known reservoir outside of humans. After recovering from an infection, 3-5% of humans become carriers of the disease. The bacteria infect the intestinal tract and occasionally the bloodstream. There are over 100 strains of Salmonella typhi but only a few strains causes typhoid fever. 100,000 organisms of Salmonella typhi make up an infectious dose, and the disease is typically spread through feces and urine of infected people in contaminated food and water.
History of Typhoid Fever
Typhoid fever has harassed mankind since the beginning of civilization. In 1998, an article in the New England Journal of Medicine suggested that the death of Alexander the Great at the age of 32 on 13 June 323 CE was caused by typhoid rather than poison or malaria. Researchers at the University of Maryland's School of Medicine argued that Alexander's symptoms- sharp abdominal pain, chills, and steadily rising fever- matched the symptoms of typhoid fever. Historical accounts suggested that Alexander's body did not deteriorate for several days following his death. Although the tale was possibly exaggerated, the event could be explained by ascending paralysis, a complication of typhoid, which causes slow paralysis from the feet up. A body may seem dead as the paralysis develops before he actually died. Other scholars have suggested that West Nile Virus was the disease that killed Alexander.
Prince Albert, the Consort of Queen Victoria, contracted typhoid fever and died four weeks later in December 1861. During his illness, he experienced intermittent but increasingly more severe fevers that led to delirium, a worsening cough, and salmon-colored skin lesions on his torso. The son of Albert and Victoria, Edward, also died of typhoid.
Typhoid fever had always threatened densely population areas with inadequate sanitation. In the settlement of Jamestown, Virginia, the first permanent English settlement in North America, outbreaks pf typhoid fever was a constant threat to survival. Between 1607 when the colony was founded and 1624, at least 6,000 settlers died from typhoid fever. By 1623, only 4,500 inhabited the settlement. During the Spanish American War in 1898, typhoid fever raged through the armies. 82% of all sick soldiers suffered from typhoid, which also accounted for 87% of total deaths from disease. During the South African War (1899-1902), the British lost more to typhoid (13,000 soldiers) than those that died due to battle (8,000 soldier).
The Salmonella typhi bacteria were first described by Karl Joseph Eberth, a German bacteriologist, in 1880. Eberth found the bacteria in the spleen and mesenteric lymph nodes of a patient who died of typhoid fever. Robert Koch had also observed and recorded the bacilli. In 1884, Georg Theodor August Gaffky, another German bacteriologist who worked under Robert Koch, confirmed the Salmonella typhi bacteria as the causal agent of typhoid. At first the bacterium was called Eberth Bacillus. In 1896, the British pathologist Sir Almroth Wright and his team developed the first vaccine of heat-denatured whole-cell typhoid bacilli. During World War I, British troops were immunized and largely escaped the disease.
In the Journal of American Medical Association published on 15 June 1907, George Soper, a sanitary engineer, revealed the results of his investigation into a typhoid outbreak at the home of Charles Henry Warren, a wealthy New York City banker. 6 of the 11 people in the house contracted the illness. At first, Soper suspected clams or other contaminants, but then discovered that the family's cook, Mary Mallon, an Irish immigrant, was a healthy carrier of the typhoid bacteria. 'Typhoid Mary' was the first healthy carrier of typhoid discovered in the United States. In March 1907, Soper found Mallon, who was serving as a cook in a Manhattan house. He told her she was spreading disease through her cooking, and demanded samples of her feces, urine and blood for tests. She chased him away with a carving fork.
When Soper carefully charted Mary Mallon's work history, out of the 8 households she cooked for, 7 had typhoid outbreaks. On this evidence, the New York City health inspector removed Mallon to be tested in March 1907. Salmonella typhi bacteria were discovered in Mallon's feces samples. Mallon was moved to Riverside Hospital on North Brother Island near the Bronx. She remained in the hospital for three years and protested every moment of her captivity. When she was released in 1910, the New York City health commissioner Ernst J. Lederle helped Mallon locate a job washing clothes.
Mallon's new occupation did not afford the same social and economic opportunities as her previous job as a cook, and Mallon felt authorities treated her unjustly. Unconvinced that her cooking caused the deadly disease, Mallon disappeared and returned her former occupation. In 1915, she was working in Sloane Maternity Hospital in Manhattan as a Mrs. Brown when a typhoid outbreak in the hospital led authorities to Mallon. She was returned to North Brother Island where she was kept in isolation for 23 years until her death. Children of former employees reported that in addition to a working in the laboratories, Mallon apparently baked and sold cakes on the hospital grounds. At the time of her death, Typhoid Mary was one of hundreds of healthy carriers to the Salmonella typhi bacteria in New York City. Many later believed her harsh treatment revealed underlying social prejudices against her Irish background.
History of Typhoid as a Biological Weapon
The Salmonella typhi bacteria were weaponized by the Japanese biological weapons program Unit 731. Like cholera, typhoid was used to contaminate drinking water. Chinese, Russian, Korean and American prisoners of war were injected with typhoid bacteria to study the disease. Reports suggested that the Japanese infected rivers between Manchuria and the Soviet Union with typhoid bacteria, but with the successful invasion of the Soviet Union in 1939, the effectiveness of the typhoid was never determined.
Reports by the International Committee of the Red Cross (ICRC) released 50 years after the incident revealed that the Israeli forces, at the siege of Acre in 1948, released typhoid bacteria into the city's water supply. According to Dr. Uri Milstein, an Israeli historian, a typhoid outbreak seized the city a few days before the city fell. Israeli soldiers disguised as Arabs were caught on 23 May 1948 in Gaza near wells. Egyptian authorities maintained these soldiers carried liquid with dysentery and typhoid bacteria. The Israeli soldiers were charged, convicted, and executed. The Israelis have denied all charges of the use of biological weapons.
In 1972, the Order of the Rising Sun, a US extremist group dedicated to the rise of a new master race, was found with 30-40 kilograms of typhoid bacteria cultures. The group had intended to use the bacterial agents against water supplies in Midwestern US cities including Chicago and St. Louis. In September 1984, in an attempt to influence local elections in Antelope, Oregon, it was suspected that the Rajneesh cult contaminated local salad bars with Salmonella enterica, a variant of Salmonella typhi. Hundreds were affected, 45 were hospitalized but no fatalities resulted.
Typhoid fever in aerosolized form can be a potential biological weapon, and sources reported that both Iran and Iraq experimented with typhoid fever as a possible biological weapons agent.