Salmonellosis: Symptoms, Sources, Treatment, and Prevention

Salmonellosis is a common foodborne illness caused by non-typhoidal Salmonella serovars (e.g., S. Enteritidis, S. Typhimurium). The CDC estimates 1.35 million US cases annually.

Transmission

• Contaminated food: raw/undercooked eggs, poultry, meat, unpasteurized milk/juice, raw produce (sprouts, melons).
• Cross-contamination in the kitchen.
• Animal contact: reptiles, amphibians, poultry, livestock; petting zoos.
• Person-to-person: fecal-oral route (poor hand hygiene).
• Waterborne: contaminated recreational or drinking water.

Clinical Presentation

• Incubation: 6–72 hours (typically 12–36h).
• Symptoms: Diarrhea (often bloody), fever, abdominal cramps, nausea, vomiting, headache, myalgia.
• Duration: 4–7 days; self-limited in healthy adults.

Complications

• Dehydration/electrolyte imbalance (high risk: infants, elderly, immunocompromised).
• Bacteremia → metastatic infections (osteomyelitis, meningitis, endocarditis, abscesses).
• Reactive arthritis (post-infectious, HLA-B27 associated).
• Irritable bowel syndrome (post-infectious).

Diagnosis and Treatment

• Stool culture or PCR (GI pathogen panel).
• Supportive: Oral rehydration (ORS); IV fluids if severe dehydration.
• Antibiotics NOT routinely recommended for uncomplicated gastroenteritis (may prolong shedding, increase relapse).
• Indications for antibiotics: Severe disease, bacteremia, immunocompromise, extremes of age, extraintestinal spread. First-line: azithromycin (children), fluoroquinolone or TMP-SMX (adults); ceftriaxone for severe/sepsis.
• Antimotility agents (loperamide) contraindicated in bloody diarrhea/fever.

Prevention (CDC "Four Steps")

1. Clean: Wash hands, surfaces, produce.
2. Separate: Raw meat/poultry/seafood from ready-to-eat foods.
3. Cook: Poultry 165°F, ground meat 160°F, eggs until yolk firm.
4. Chill: Refrigerate ≤40°F within 2 hours (1 hour if >90°F).

Additional: Avoid raw milk, raw dough, unpasteurized juice; wash hands after animal contact.