North Carolina Department of Health and Human Services North Carolina Public Health
Division of Public Health (DPH) Site Navigation
Other Important NC Public Health Links
NC Publich Health Partnerships
Centers for Disease Control and Prevention Links

Get Adobe Reader to Access PDF files -- It's free
 

Microbiology - Parasitology

Diagnostic specimens for examination for the presence of human parasites are accepted from public health care providers only. Diagnostic specimens for parasitologic examination are accepted only from symptomatic patients. Reference specimens for confirmation of parasite identity or further identification are accepted from all laboratories.

Feces and other specimens are examined for eggs, cysts and larvae of the intestinal parasitic worms and protozoa. Specimens are also accepted for examination in less frequently encountered parasitic infections; blood smears for parasitic blood diseases are examined. Reference specimens preserved in polyvinyl alcohol (PVA) fixative or stained slides prepared from preserved material are also accepted. Arthropods are referred to the Entomology Department at N.C. State University through the Insect and Plant Disease Clinic (919-515-9530) for identification for a fee of $30. Submitter should contact the clinic directly to arrange. Water samples thought to be the source of human giardiasis will be accepted only by special arrangement. Please contact the Microbiology Branch for instructions on collection. Consultation and bench training in parasitology are provided upon request. Testing for Cryptosporidium and Cyclospora are offered upon request; testing for Microsporidium is NOT available at this time.

Specimen Collection

Clearly label each specimen with patient´s name, and fill out DHHS form #1245 completely. Unlabeled specimens will NOT be examined; they will be discarded.

Lab records are computerized and the following data are required: patient name, patient Social Security Number (or assigned number), date of birth, patient Medicaid number (if applicable), submitter Federal Tax Number (Employer Identification Number), submitter return address, specimen collection date and specimen source. Without these data, specimen records cannot be entered into the computer, nor can a report of results be printed. Other data are helpful for epidemiological follow-up and for statistical purposes.

Note: CLIA regulations require the following information on all test requistions:

Intestinal Parasites

Fecal Specimens: Collect specimen following instructions in the Parasitology mailer available from the laboratory mailroom by ordering on-line at https://slphreporting.ncpublichealth.com/labportal/ , or in any commercially available parasite collection kit containing 10% formalin as a preservative. Do not contaminate with dirt, urine or paper. Place feces in a vial of 10% formalin. Break up any large pieces and shake or stir well. Place caps on securely to avoid leakage. Leaking specimens constitute a biological hazard; leaking specimens will not be tested. Label tube with patient's name. Three specimens collected on alternate days are recommended, e.g., Monday, Wednesday and Friday. If three (3) specimens are collected, mail all three at the same time.

PVA Preserved Fecal Specimens: Please consult the Microbiology Branch for additional information. Collect feces in clean container. Avoid contamination with urine. Place an amount up to the "fill line" in a small bottle of PVA fixative. Break up large pieces and stir well. Label bottle with patient's name.

Transparent Tape Slides for Pinworms: Tear off a piece of tape about 2 inches long. DO NOT use frosted or "magic" tape. Frosted tape is not transparent and cannot be read with the microscope. Fold tape over the end of the finger or a tongue depressor with the sticky side out. Do not let the tape wrinkle. Spread the patient's buttocks to expose anus. (Preferably take the specimen immediately after waking. Do not clean anal area before taking specimen.)  Press sticky side of tape gently to anus two or three times. Lay tape smoothly on a clean glass slide, sticky side down. Press gently to slide with a piece of tissue or gauze. Cut off the tape which overhangs the slide. Label slide with patient's name. Place slide in plastic or styrofoam container for mailing. Do not use envelopes for mailing glass slides as they are likely to break in transit. WASH HANDS IMMEDIATELY. Commercial collection devices may also be used.

Other Clinical Materials: Collect specimen aseptically following proper procedure for type of specimen. Place in sterile container; label with patient's name.

Whole Worms or Proglottids: Whole worms should be preserved in 70% alcohol, if possible.  Place in plastic or glass container; label with patient’s name.  Proglottids may be preserved in 10% formalin or placed in saline or 70% alcohol.  Parasitology mailer may be used if it is large enough, as it contains 10% formalin.

Blood and Tissue Parasites

Blood Smears for Malaria and Other Blood Parasites: Collect blood from a finger stick or from venipuncture. Prepare two thin smears and two thick smears. A thin smear is made using less than a drop of blood and is "feathered" with the feather near the center of the glass slide. The thick smear is simply a drop of blood placed in the center of the glass slide with slight spreading. Smears should be allowed to air dry. Do not use fixative. Label the slides with the patient's name with a diamond tipped glass marker. If frosted end slides are used, label the frosted end with pencil.

Corneal Scrapings for Acanthamoebae Contact the Microbiology Branch at least 24 hours prior to taking specimen.

Arthropods

Arthropods are referred to the Entomology Department at NC State University through the Insect and Plant Disease Clinic (919-515-9530) for identification for a fee of $30. Submitter should contact the clinic directly to arrange.

Specimen Shipment

Always use double-walled shipping containers or equivalent that meets safety requirements. Mailers for submitting formalin-preserved specimens are available online at http://slph.ncpublichealth.com/. Multiple tubes or specimens should be packaged individually in leak-proof containers so as not to contaminate the requisitions. Mailers or packages not supplied by the State Laboratory should have "Parasitology" plainly marked on the outside of the package. This ensures that packages and mail will be delivered directly to the proper unit, and eliminates needless and possibly hazardous exposure of non-technical staff. To facilitate handling, the following general suggestions are made:

  1. Write patient´s name on specimen tube or slide. Unlabeled specimens will NOT be tested
  2. Place specimens tube inside plastic bag
  3. Place properly completed identification DHHS form #1245 in outer container outside the plastic bag, to avoid contamination in case of breakage or leakage
  4. When using U.S. Mail, use first-class postage, and place return address on the outside of the container
  5. When unusually large numbers of specimens are anticipated (as an outbreak in a day care center), the Microbiology Branch should be alerted by telephone at (919) 733-7367 so that preparations may be made

Reporting Procedure and Interpretation

Specimen results are usually reported within two to three days of receipt. Reference specimens which are submitted to the CDC may require several weeks.

An estimate of few, moderate, or many will be reported only with certain organisms where quantity may have a correlation with worm burden (such as Ascaris, Trichuris, and hookworms) or be an indicator for treatment (such as Blastocystis hominis). Blood parasites reported will include quantitation.

A report of Entamoeba coli is not to be confused with E. histolytica (reported as Entamoebahistolytic/Entamoeba dispar complex). E. coli is a non-pathogenic commensal amoeba often found in the human gastrointestinal tract, and is reported only as an indication of unsanitary conditions relating to the patient, such as poor personal hygiene.

Reports of "no parasites found" in water samples for G. lamblia are not significant due to the low recovery rate of the cysts from water and the unavailability of a satisfactory test for use on water samples.

Reports are returned to the submitting agency only; therefore, the submitter is responsible for sending copies and/or making reports to any other agency. DHHS form #1245 submitted with the specimen is also the report form on which results are recorded before it is returned to the submitter. The submitting agency is responsible for maintaining reports in the patient´s file. Results can be accessed via the secure web page for results at https://slphreporting.ncpublichealth.com/lims.

See also:

Last Modified: May 3, 2012 1:10 PM