Brief Description

The Bacteriology Unit examines feces  for the presence of enteric pathogens, namely Salmonella serotypes. Referred isolates will be characterized by various methods, such as biochemical reactions, serogrouping and serotyping, Polymerase Chain Reaction (PCR), and Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF). Next Generation Sequencing will be performed to identify and characterize isolates. All isolates of Salmonella, recovered from specimens by other clinical laboratories in Georgia should be referred to the Bacteriology Unit, either directly or through the Emerging Infections Program (EIP) site.

Laboratory Unit



  • Biochemicals
  • Serotyping
  • Whole Genome Sequencing

Specimen Collection

  • Feces Specimens:
    • Collect in the ParaPak C&S outfit, orange-colored top (do not use the Parasitology O&P kit, blue and white-colored top, because it contains formalin that kills bacteria).  Collect freshly passed feces as soon as possible after onset of illness and before antimicrobial therapy has been initiated. The patient should be cautioned against the use of antacid, barium, bismuth, anti-diarrheal medication, or oily laxatives prior to specimen collection. An appropriate (i.e., bloody, slimy, watery) area of stool should be selected and sampled with the collection spoon provided on the cap of the container.  Add specimen only to the red line on the vial, tighten the cap securely, and invert several times.  The solution in the vial should be salmon colored before the specimen is added.  Three consecutive specimens collected on different days during the acute stage of diarrheal disease are recommended (first three days).
  • Rectal swabs:
    • Those containing detectable feces may be collected and placed in a Culturette with Stuarts, Cary-Blair, or other commercially available transport medium, if a feces specimen cannot be obtained.
  • Culture isolate:
    • Submit an overnight, pure culture of the isolated bacteria on carbohydrate-free media available commercially (TSA, TSI and LIA are acceptable).


Specimens and cultures can be maintained at room temperature (15-30°C) during transit. When large numbers of specimens are expected (such as in an outbreak), please alert the Bacteriology Unit by telephone 404-327-7991 before mailing.

Acceptable Specimen Type(s)

  • Feces
  • Rectal Swabs

Test Request

Possible Results

Identification to the genus, species, and serotype level.

Reference Range


Unacceptable Conditions

  • Specimens submitted in wrong preservative, e.g., PVA or 10% formalin.
  • Multiple specimens collected on the same day (only one specimen will be tested).
  • Missing testing requisition
  • Missing minimum of 2 patient identifiers
  • Improper labeling
  • Improper storage/transport of specimen
  • No specimen received (empty collection tube).
  • Wrong specimen type
  • Specimens damaged, broken, or leaking upon arrival
  • Name or patient identifier mismatch
  • Specimens received more than 4 days after collection ( per Para Pak C & S package insert).
  • Swab submitted in Para-Pak C&S outfit

Interfering Substances


Result Reported

3-5 business days


Fee schedule

LOINC/Order Codes

17563-8 (Culture Order code 1110) (Clinical Specimen Order code: 114002)