Listeriosis

Reportable by Providers and Laboratories

About this Reportable Disease

Infectious agent: Listeria monocytogenes, a gram-positive rod-shaped bacterium

Description of illness: The bacterium Listeria monocytogenes causes listeriosis, a rare but serious foodborne disease. It primarily affects older adults, pregnant women, infants and those with weakened immune systems.  Older and immunocompromised adults often experience septicemia and meningitis, while pregnant women experience fever, fatigue and muscle aches.  Infection of pregnant women can lead to fetal loss or life-threatening infections in newborns.

Interactive Disease Data


Laboratory Reporting for this Disease

Listeria species

TEST NAME Listeria species
DISEASE/DISORDER Listeriosis, bacteremia
ALTERNATE NAME(S) Listeria Culture
METHODOLOGY Culture
SPECIAL INSTRUCTIONS
  • Isolate submission is REQUIRED for laboratories.
  • Contact CEDEP if a foodborne outbreak is suspected.
ORDERING INFORMATION Lab Web Portal

Specimen Requirements

Patient Preparation
  • None
Specimen Collection
  • Pure culture from normally sterile sites on non-selective media slants such as Trypticase Soy, Blood, or Chocolate agar.
Specimen Labeling
  • Specimen should be labeled with at least two unique patient identifiers along with specimen source and match accompanying test order.
Specimen Processing
  • None
Specimen Storage and Preservation
  • Store isolate in ambient conditions
Specimen Transport
  • Transport isolate in ambient conditions.
  • Do not send refrigerated or frozen.
  • All infectious substance shipments must conform to U.S. Department of Transportation (DOT) Hazardous Materials Regulations (HMR 49 C.F.R. Parts 171-180). 
Specimen Acceptability and Rejection
  • Specimens that do not meet all specimen requirements will be rejected.
Testing Location
  • Nashville

Laboratory Reporting

Reporting requirements apply to all laboratories located within Tennessee, as well as laboratories outside of Tennessee that test residents of Tennessee, including laboratories located within healthcare facilities. Healthcare providers and laboratories in the same healthcare facility both have a duty to report. The type of organisms and analytes laboratories must report to TDH for 2026 are indicated, and there are several ways laboratories can report results to TDH.

Information about this Reportable Disease for Healthcare Providers

Clinical Summary

  • Listeriosis is caused by Listeria monocytogenes and can present as intestinal illness or invasive/focal infection; clinical manifestations vary by host risk factors and site of infection. Pregnancy-associated listeriosis is often mild/flu-like in the pregnant patient but can result in fetal loss, preterm labor, and neonatal sepsis/meningitis.
  • High-risk groups include pregnant patients, older adults, and immunocompromised patients; maintain suspicion in compatible syndromes and exposure history (including recalls or known contaminated foods).
  • Diagnosis is typically by culture from a normally sterile site (e.g., blood, CSF) in invasive disease; coordinate laboratory/public health steps per local guidance when listeriosis is suspected/confirmed.
  • Treatment is antibiotic-based and time-sensitive for invasive disease; CDC provides a management framework for exposed high-risk patients and for those with suspected/confirmed disease in Caring for Patients with Listeriosis.
  • In Tennessee, listeriosis is a reportable condition; use TDH disease guidance and reporting requirements as applicable for case investigation and outbreak detection.

Healthcare Provider Reporting

Healthcare reporting requirements apply to all providers located within Tennessee, as well as providers whose patients reside in Tennessee.

Providers must report cases of all diseases and conditions listed through one of these methods:

• Mail or fax a completed PH-1600 form to your local health department or fax to the state health office at (615) 741-3857

• Send automatically via electronic case reporting (eCR). See this TDH webpage for more information on eCR, register at the Trader Partner Registration website, or contact MU.Health@tn.gov for assistance.

• Submit online via NBS. NBS is TDH's reportable disease system. To request an NBS account for reporting Complete this user survey to request an NBS account for reporting. 

• Blood lead levels can be sent via fax ( (615) 741-3857), entered online, or reported using the instructions at this link. 

Information about this Reportable Disease for the Public

What It Is

Listeriosis is an infection caused by the bacterium Listeria monocytogenes, typically from eating contaminated food. It can affect the gut or spread to other body parts (invasive). Occurs more often in pregnant women, newborns, older adults, and immunocompromised persons. Though rare, it is among the more serious foodborne infections due to high fatality in some groups. 

Types

Non-invasive (intestinal) illness—limited to gut symptoms like diarrhea/vomiting. Invasive illness—bacteria spread beyond the intestines (blood, brain, placenta). Pregnancy-associated type is mild in the mother but can severely affect the fetus/newborn. Neonatal onset—early or late in newborns from maternal transmission. 

Signs and Symptoms

Gastrointestinal: diarrhea, vomiting, fever, and muscle aches in less-severe cases. Flu-like symptoms: fever, chills, fatigue, headache in many patients. Neurological/invasive: stiff neck, confusion, loss of balance, seizures. In pregnant women, symptoms may be mild or absent, but fetal risk is high (miscarriage, stillbirth).

Treatment

Most mild intestinal cases recover without antibiotics; supportive care (fluids, rest) may suffice. Invasive listeriosis requires prompt antibiotic therapy, typically intravenous. Common regimen: Ampicillin (often with Gentamicin) for severe disease. Pregnant women with suspected invasive infection should get specialist care and antibiotic treatment to protect the mother and baby. 

This Page Last Updated: March 25, 2026 at 8:53 PM