What is the incubation period for human salmonellosis?

• A. 12 to 24 hours
• B. 24 to 48 hours
• C. 12 to 72 hours
• D. 3 to 5 days

Answer: (C)

Salmonellosis has an incubation period that is the time from ingesting Salmonella to the onset of illness. This interval is variable because the amount of bacteria you swallowed and individual factors influence how quickly symptoms appear. In practice, illness typically starts within 12 to 72 hours after exposure. Many cases show symptoms around 12 to 36 hours, but it can take up to about three days in some people. Narrower windows like 12–24 or 24–48 hours don’t capture the full range, and 3–5 days is longer than usual for Salmonella. Therefore, the broad 12 to 72 hours best reflects the typical variability.