are there different varieties of this fever?
Yes, like Paratyphoid B.
Paratyphoid fever
Paratyphoid B is more frequent in Europe. It can present as a typhoid-like illness, as a severe gastroenteritis or with features of both. 
who was the president that served the shortest term William Henry Harrison which country did he belong to? United States where was he born? Charles City County, Virginia. who were his parents? Benjamin Harrison V and Elizabeth (Bassett) Harrison. did he have any other career apart from that of a politician? Yes, military career. how did he step into politics? He campaigned among his friends and family for a post in the Northwest Territorial government. and did he hold any position in the government before becoming the president? As acting territorial governor. of which place? Indiana Territory. why was his presidential tenure so short? He died of either typhoid, pneumonia, or paratyphoid fever 31 days into his term, becoming the first president to die in office and the shortest-serving president in U.S. history. what are the symptoms of the third disease? Fever, headache, abdominal pain and malaise. what are its causes? Any of three strains of "Salmonella" paratyphoid: "S." Paratyphi A, "S. schottmuelleri" or "S. hirschfeldii". how does it spread? Humans and, occasionally, domestic animals are the carriers of paratyphoid fever.
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Paratyphoid fever [SEP] Paratyphoid B
Paratyphoid B is more frequent in Europe. It can present as a typhoid-like illness, as a severe gastroenteritis or with features of both. Herpes labialis, rare in true typhoid fever, is frequently seen in paratyphoid B. Rarely a subdural empyema can occur. Diagnosis is with isolation of the agent in blood or stool and demonstration of antibodies antiBH in the Widal test. The disease responds well to chloramphenicol or co-trimoxazole.