Short answers, pulled from the story.
Typhoid fever is caused by the bacterium Salmonella enterica serotype Typhi, which spreads through food or water contaminated with the feces of an infected person. Humans are the only known carriers; there are no animal reservoirs. Risk factors include limited access to clean drinking water and poor sanitation.
Without treatment, the risk of death from typhoid fever may be as high as 20%. With prompt antibiotic treatment, that rate falls to between 1% and 4%. In 2015, typhoid fever caused approximately 149,000 deaths worldwide, down from 181,000 in 1990.
Mary Mallon, known as Typhoid Mary, was a personal cook for upper-class families in New York City who was linked to 51 cases and 3 deaths between 1907 and 1915. She became the first confirmed asymptomatic carrier of an infectious disease, proving that typhoid fever could be transmitted by someone who showed no symptoms themselves.
British bacteriologist Almroth Edward Wright developed the first effective typhoid vaccine at the Army Medical School in Netley, Hampshire, introducing it in 1896. It was first used in combat during the Second Boer War in South Africa, and Wright later produced 10 million doses for British troops on the Western Front in World War I.
Notable deaths from typhoid fever include Franz Schubert, who died on the 19th of November 1828 at age 31, and Wilbur Wright, co-inventor of the airplane, who died in 1912 at age 45. Prince Albert of Saxe-Coburg and Gotha, husband of Queen Victoria, died on the 14th of December 1861. William Henry Harrison, the ninth U.S. President, died of typhoid 32 days into his term in 1841, the shortest presidential term in American history.
Multidrug-resistant typhoid, which defeats ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, and streptomycin, is now widespread. Ciprofloxacin resistance is an increasing problem in the Indian subcontinent and Southeast Asia. Since November 2016, Pakistan has faced an outbreak of extensively drug-resistant typhoid, leading many treatment centers to shift to ceftriaxone or azithromycin as first-line options.