Arthropods (e.g. Mites, Lice, Fleas, Maggots, and Ticks) – Microscopy

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.

This page provides routine microscopic testing information for arthropods at Public Health Ontario (PHO). Arthropods (also known as ectoparasites) may include mites (e.g. Acariformes), lice (e.g. Anoplura), fleas (e.g. Siphonaptera), maggots (e.g. Diptera), hard ticks (e.g. Ixodidae), and soft ticks (e.g. Argasidae).

This page is specific for microscopic examination of suspected arthropods identified from human specimens. Additional testing options may exist for the diseases potentially carried by these arthropods. Refer to the PHO Test Information Index for a list of disease-specific tests available.

Note: For tick identification, the eTick.ca image-based platform is available for free to the public and healthcare providers as an alternative option instead of tick submission to PHO.

Updates:
As of November 3, 2023, the arthropod, scabies, Demodex, lice, myiasis, and tick test information webpages were combined into the current webpage. The Labstract LAB-SD-146 Changes to Passive Tick Surveillance Program in Ontario has also been also integrated into the current webpage.

Testing Indications

Mites, lice, fleas, and maggots: Microscopic identification is indicated for suspected arthropods extracted from individuals with clinical evidence of infestation such as scabies, pediculosis, tungiasis, or myiasis.

Ticks: Microscopic identification is not indicated for clinical management. However, voluntary submission of ticks extracted from individuals following a tick bite is offered at PHO to monitor new and emerging tick populations in Ontario. This voluntary provincial surveillance program helps collect information on which areas in Ontario have a higher number of certain ticks. In turn, this information can be used to develop local messaging on preventing tick bites in the region. Refer to the Tick Submission and Testing FAQ for additional details.

Acceptance/Rejection Criteria

Specimens are only accepted if extracted from humans and submitted by healthcare providers or health units to a licensed specimen collection centre. The following specimens will be rejected:

  • Specimens extracted from animals (e.g., pets) or the environment
  • Specimens submitted by non-authorized healthcare professionals
  • Requisition form missing mandatory information

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit

Arthropod or ectoparasite identification

Suspected ectoparasite(s)

N/A

Sterile container

Scabies or mite identification

Skin scraping(s)

N/A

Sterile container

Pediculosis or lice identification

Suspected louse/lice

N/A

Sterile container

Tungiasis or flea identification

Suspected flea(s)

N/A

Sterile container

Myiasis or maggot identification

Suspected maggot(s)

N/A

Sterile container

Tick Identification

Suspected tick(s)

N/A

Sterile container

Submission and Collection Notes

1

See Special Instructions below for suggestions on specimen collection.

2

If multiple arthropods are collected from the same patient, collect all arthropods into the same container and submit only one requisition form. If multiples arthropods are collected from multiple patients, use one container and one requisition form per patient.

3

Use sterile, solid, leak-proof, prolyprophylene containers (e.g. empty Starplex containers). Do NOT use bags or envelopes.

4

To assist in specimen processing, please indicate if a specific organism (e.g. scabies or tungiasis) is suspected.

5

Complete all fields of the requisition form, including:

  1. Test(s) requested and indications for testing
  2. Patient setting/population
  3. Clinical information including symptom onset date or if asymptomatic
  4. Travel history – the country/region of exposure should be stayed otherwise testing may be delayed or cancelled
  5. For ticks: attachment/feeding duration
6

Label the specimen 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. Failure to provide this information may result in rejection or testing delay.

Limitations

PHO’s laboratory does not return back to submitters any specimen submitted for identification.

Storage and Transport

A minimal amount of sterile normal saline or 70-100% ethanol may be added inside the sterile container to barely cover the suspected arthropod and prevent dehydration. Place specimen container in a biohazard bag and seal. Store at room temperature or frozen and ship to PHO’s laboratory. All clinical specimens must be shipped in accordance to the Transportation of Dangerous Goods Act.

 

Special Instructions

Scabies mites: Use the flat edge of a scalpel or tongue depressor to scrape the skin at the track margins (the skin is usually desquamating easily).

Pediculosis lice: Use fine-toothed combs or fine-tipped tweezers to extract the louse and any eggs (nits) if found.

Tungiasis fleas: After skin antisepsis, use sterile forceps or curets to aseptically extract the burrowed flea followed by appropriate wound management.

Furuncular myiasis maggots: After skin antisepsis, use an occlusive dressing (e.g. petroleum jelly, beeswax, liquid paraffin) to partially extrude the burrowed maggot, then use lateral pressure, vacuum extraction, and/or surgical excision to aseptically extract the maggot followed by appropriate wound management.

Ticks: Use fine-tipped tweezers to grasp the tick as close to skin’s surface as possible and pull upward with steady, even pressure to carefully extract the intact tick, then thoroughly clean the bite area (e.g., with hand sanitizer, rubbing alcohol, iodine scrub, or soap and water). Note: if the tick breaks off, remove the remaining imbedded mouth parts with the tweezers; if unable to remove the mouth parts easily, leave them in the skin and let heal.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Mites, Lice, Fleas, and Maggots: Identification is performed Monday to Friday at PHO’s Toronto laboratory site. Turnaround times are up to 2 (mites and maggots), 3 (lice), or 7 (fleas) business days from receipt at PHO’s laboratory.

Ticks: Identification is performed Monday to Friday at PHO’s Sault Ste. Marie laboratory site. Turnaround time is up to 21 business days from receipt at PHO’s laboratory, but delays may occur during peak seasons (May/July to October/November).

Test Methods

Arthropod identification is performed visually and assisted by stereomicroscopy and traditional microscopy to identify morphological features.

PHO does not perform disease-specific pathogen testing (e.g. PCR) on the arthropods received.

Interpretation

Pathogenic arthropods and their stages will be identified as much as feasible to the species level depending on diagnostic features present. If the structure is not an arthropod (e.g. vegetable, mucus, or synthetic material), it will be reported as such. If the structure is not a human parasite (e.g. animal or environmental arthropods), it will be reported as not originating from a human source and of no clinical significance.

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. If a patient would like to know their tick identification results, they should consult with their healthcare provider. Due to privacy concerns, laboratories do not provide results directly to the general public.

Accepted Arthropods

The following arthropods (removed from a human or vicinity) will continue to be identified at PHO laboratory:

  • suspected lice fleas
  • bedbugs
  • maggots
  • mites
Updated 3 Nov 2023