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Indirect Immunofluorescent Assay (IFA) – IgG

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Accredited by the Standards Council of Canada to Laboratory no. 594 (ISO/IEC 17025)

Requisition Forms

Reference Details


Detection of IgG antibodies to Anaplasma phagocytophilum by IFA.

Test Category:
Anaplasma phagocytophilum
Illnesses and Diseases:
  • Human granulocytic anaplasmosis (HGA)

Fresh human serum. 

Minimum volume required is 0.25 mL.

Hyperlipemic, hemolysed or contaminated sera may yield erroneous results.

Collection Method:

Collect blood in serum separator tubes.

Specimen Processing, Storage and Shipping:

Transfer an aliquot of serum to a 1.5 ml screw-top vial with O-ring (Sarstedt vial). Store specimens refrigerated up to 5 days or store frozen until shipped for testing.  Ship frozen on dry ice or with freezer packs.  

Transportation of Dangerous Goods:

Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.


Patient Criteria:

Appropriate clinical symptoms with potential exposure to Ixodes spp. ticks within the previous 5-21 days prior to symptom onset . Clinical evidence of Anaplasmosis is characterized by an acute onset of fever with one or more of the following non-specific symptoms: chills, malaise, headache, myalgia, arthralgia, leukopenia, thrombocytopenia or elevated hepatic transaminases.

Accompanying Documentation:

Completed Requisition for Serological Testing for Selected Zoonotic Agents. If possible, include the clinical history and lab results performed at local or provincial laboratories.


Specimens may be subject to rejection if they are not the appropriate sample type, have insufficient volume, or are not accompanied by relevant patient information.

Methods and Interpretation of Results:

Commercial IFA kit. This is a semi-quantitative test for the detection of IgG antibodies to A. phagocytophilum.  A four-fold or greater increase in IgG titre between two serum samples drawn 1 to 2 weeks apart is considered presumptive evidence of a recent or current infection with A. phagocytophilum.  An IgG endpoint greater than 1:64 alone should not be relied on for a diagnosis of Anaplasmosis.

Initiation of antibiotic treatment prior to testing may result in decreased antibody production which will affect the outcome of serological testing.

Turnaround Time:

21 calendar days.

Phone #: (204) 789-6068
Fax: (204) 789-2082
  1. Bakker, J.S., Dumler, J.S. 2008. Human Granulocytic Anaplasmosis. Infect. Dis. Clin. N. Am. 22:433-448.
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