Typhimurium

Salmonella enterica subsp. enterica serovar Typhimurium, commonly referred to as Salmonella Typhimurium, is one of the most frequent serovars causing salmonellosis in humans. It has a broad host range, including humans, poultry, cattle, and swine, and is frequently associated with contaminated food products such as poultry, eggs, and dairy, as well as produce contaminated by animal feces.

In humans, Typhimurium typically causes acute gastroenteritis characterized by diarrhea, abdominal cramps, fever, nausea, and vomiting. The illness is usually self-limiting, lasting several days, but can be more severe in young children, older adults, or immunocompromised individuals, and rare invasive infections may occur (bacteremia, meningitis).

Pathogenesis involves virulence factors encoded on Salmonella Pathogenicity Islands, including type III secretion systems SPI-1 and SPI-2, enabling invasion of intestinal cells and survival within macrophages. The organism persists in the intestinal tract and environment; strains can acquire antimicrobial resistance, including multi-drug resistance patterns such as ACSSuT seen in DT104 and related lineages.

Diagnosis is by culture followed by serotyping to determine O and H antigens, with PCR or genomic sequencing as adjuncts.

Treatment is primarily supportive; antibiotics are reserved for severe disease or invasive infections, and resistance monitoring is important in empirical therapy.

Prevention focuses on food safety, proper cooking and pasteurization, and farm-level controls; vaccines exist for poultry to reduce carriage and contamination.

In research, Salmonella Typhimurium strains such as LT2 and SL1344 are widely used as model systems to study enteropathogenesis and host-pathogen interactions.