Burkholderia mallei and Burkholderia pseudomallei- Confirmation

Consistent with O. Reg. 671/92 of the French Language Services Act, laboratory testing information on this page is only available in English because it is scientific or technical in nature and is for use only by qualified health care providers and not by members of the public.

Background
This page provides details on the identification of Burkholderia mallei and Burkholderia pseudomallei at Public Health Ontario (PHO). Burkholderia mallei is the causative agent of glanders, a highly contagious disease primarily affecting horses, but can also be transmitted to humans. Burkholderia pseudomallei causes melioidosis, a potentially fatal disease that affects both humans and animals. These organisms can produce a remarkably wide range of clinical outcomes, ranging from subacute, localized infections to severe organ system damage and overwhelming septicemia.

For information regarding other testing options, refer to the following PHO webpages:

Aerobic bacteria identification : Bacterial cultures – Aerobic – Reference ID/Confirmation
Anaerobic bacteria identification: Bacterial cultures – Anaerobic – Reference Identification/Confirmation
Aerobic bacteria susceptibility testing: Antimicrobial Susceptibility Testing – Aerobic Bacteria
Anaerobic bacteria susceptibility testing: Antimicrobial Susceptibility Testing – Anaerobes

Updates

The turnaround time for further confirmatory testing of Burkholderia mallei or Burkholderia pseudomallei at National Microbiology Laboratory (NML) has been updated to reflect their published turnaround time.
A table of possible results and corresponding interpretation has been added.

*Uncontrolled print copy. Valid only on day of print: 13 Oct 2025.

Testing Indications

Submitting laboratories must contact Public Health Ontario laboratory Customer Service Centre at 416-235-6556 or 1-877-604-4567 prior to submission of the isolate.

Submit the isolate for identification confirmation if it is a non-fermenting gram-negative coccobacilli or small rods or rods with bipolar “safety pin” staining characteristics with colony morphology, biochemical reactions, growth characteristics, identification from an automated bacterial identification system and susceptibility patterns raising high suspicion of Burkholderia mallei or Burkholderia pseudomallei.¹

Acceptance/Rejection Criteria

Acceptable specimens include:

Pure cultures only: Mixed cultures or primary specimens (e.g. direct swabs, tissue or fluids) are not accepted
Properly labeled cultures: The patient and specimen identification on the requisition form must match the label on the culture container
Source of isolation indicated: The requisition must clearly state the source of the isolate (e.g. skin lesion swabs, blood cultures, respiratory secretions, stool)

Rejected specimens include:

Swabs: Specimens received on dry or gel-based swabs will be rejected
Primary specimens: Direct human patient samples (e.g. skin lesion swabs, blood cultures, respiratory secretions, stool and others) and direct animal samples
Missing source information: Cultures without a clearly indicated source of the isolate on the requisition will be rejected.
Mixed or non-viable cultures: These will not be tested.
Mislabeled or unlabeled cultures.

Specimen Collection and Handling

Specimen Requirements

Test Requested

Required Requisition(s)

Specimen Type

Minimum Volume

Collection Kit

Burkholderia mallei -Confirmation

Burkholderia pseudomallei –Confirmation

Reference Bacteriology Requisition

Pure viable subculture of organism on appropriate media that supports the growth

N/A

agar plate or agar slant tube

Submission and Collection Notes

Complete all fields of the requisition form, including:

Test(s) Requested: Select confirmation and identification.
Culture Information: Indicate the presumptive identification (if available) and Gram morphology; provide oxygen requirement for growth; oxidase test result; catalase test result; indicate of presence or absence of growth on MacConkey; motility
Clinical/epidemiology information.
Contact information.
Date of Collection of primary specimen from which the isolate was recovered:
Source of isolate (Mandatory):
- The number of consecutive blood cultures positive for the submitted isolate when isolates are from blood cultures
- Type of urine specimen(s) (e.g. midstream, indwelling catheter, cystoscopy etc.)
- The site and type of wound swab; be as specific as possible (e.g. animal bite, surgical wound, decubitus ulcer, etc.
- If the source was collected for surveillance or screening, write the source or body part
- The type of specimen if other than blood culture, urine or wound swab, please provide as much detail as possible

Label the culture container(s) with the patient’s first and last name, date of collection, and one other unique identifier such as the patient’s date of birth or Health Card Number. For additional information see: Criteria for Acceptance of Patient Specimens. Failure to provide this information may result in rejection or testing delay.

If the bacterial culture submitted for identification confirmation is received in a broth media (instead of on a plate) the turnaround time will be delayed by at least 24 hours.

If susceptibility testing is required, the submitter must call within 5 days of receiving final results and provide necessary information and justification for susceptibility testing request.

Do not submit multiple isolates from the same specimen or site of infection.

Primary specimens are unacceptable as they must be processed at the originating laboratory.

If full bacterial identification and susceptibility testing is clinically indicated-such as in cases involving immunocompromised patients, it must be clearly indicated on the requisition.

Limitations

Culture must be viable. Use a fresh subculture and ship in conditions to ensure viability on receipt.

Storage and Transport

Place the sealed culture in a biohazard bag and properly seal. Store at 2-8°C while awaiting shipping. The requisition form must be placed in the outer pouch of the biohazard bag, separate from the culture container. Transport a fresh subculture to ensure viability on receipt. It should be shipped to PHO’s laboratory within 48 hours of isolation. All cultures must be shipped in accordance to the Transportation of Dangerous Good Act.

Special Instructions

The sender must contact the PHO’s laboratory by calling the Customer Service Centre at 416-235-6556 or 1-877-604-4567 before submitting the isolate.

B. mallei and B. pseudomallei must be handled in accordance with the Canadian Biosafety Standards and shipped in accordance with the Transportation of Dangerous Goods Regulations.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Testing is performed daily (Monday to Friday) as received at PHO’s Toronto laboratory-. Turnaround time for test results is up to 3 days from receiving by PHO’s Toronto laboratory.

Isolates that are positive for Burkholderia mallei or Burkholderia pseudomallei are forwarded to the National Microbiology Laboratory (NML) for confirmatory testing where the turnaround time for test results is up to 4 calendar days for a preliminary result and 14 calendar days for a final result.

STAT and Critical Samples Testing

Urgent testing is available upon request by calling the Customer Service Centre 416-235-6556 or 1-877-604-4567.

Test Methods

At PHO, the identification of Burkholderia mallei or Burkholderia pseudomallei is performed using the Canadian Laboratory Response Network (CLRN) real-time polymerase chain reaction (PCR) assay. Positive results are considered presumptive, and isolates are forwarded to NML for confirmatory testing.

Interpretation

All results should be interpreted within the context of the specific clinical scenario. Due to the potential overlap in disease presentation and geographic distribution, consideration should be given to testing for other possible co-pathogens.

Burkholderia mallei:

Result	Interpretation
Not Detected	Burkholderia mallei DNA NOT detected by real-time PCR
Presumptive Detected	Presumptive Burkholderia mallei DNA DETECTED by Real-time PCR.
Inconclusive	Burkholderia mallei real-time PCR result is inconclusive due to specimen quality. Please collect additional specimens for retesting.
Invalid	Burkholderia mallei real-time PCR result is invalid. Sample is unsuitable for PCR testing.

Burkholderia pseudomallei:

Result	Interpretation
Not Detected	Burkholderia pseudomallei DNA NOT detected by real-time PCR
Presumptive Detected	Presumptive Burkholderia pseudomallei DNA DETECTED by Real-time PCR.
Inconclusive	Burkholderia pseudomallei real-time PCR result is inconclusive due to specimen quality. Please collect additional specimens for retesting.
Invalid	Burkholderia pseudomallei real-time PCR result is invalid. Sample is unsuitable for PCR testing.

Reporting

Results are reported to the physician, authorized health care provider (General O. Reg 45/22, s.18) or submitter as indicated on the requisition.

References

American Society of Microbiology. Laboratory Response Network(LRN) Sentinel Level Clinical Laboratory Protocols-Burkholderia. March 2016 . Available from: https://asm.org/articles/cphmc/laboratory-response-network-lrn-sentinel-level-c [Accessed 16 September 2025]