About Salmonella

From the nation’s leading law firm representing victims of salmonella and other foodborne illness outbreaks.

Chapter 7

How is Salmonella Infection Diagnosed?

Salmonella infection is diagnosed through testing of a stool sample. Salmonella can sometimes also be isolated from blood, urine or tissue samples.

Salmonella bacteria can be detected in stool. [5, 15] In cases of bacteremia or invasive illness, the bacteria can also be detected in the blood, urine, or on rare occasions in tissues. [5] The test consists of growing the bacteria in culture. [5, 6] A fecal, blood or other sample is placed in nutrient broth or on agar and incubated for 2-3 days. After that time, a trained microbiologist can identify the bacteria, if present, and confirm its identity by looking at biochemical reactions.

Treatment with antibiotics before collecting a specimen for testing can affect bacterial growth in culture, and lead to a negative test result even when Salmonella causes the infection. [5]

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Treatment for Salmonella Infection

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