Indirect Immunofluorescence Assay (IFA) – IgG

Detection of IgG antibodies to Borrelia hermsii by IFA.

• Relapsing fever

Fresh human serum.  Minimum volume of serum required is 0.25 mL. Hyperlipemic, hemolysed or contaminated sera may yield erroneous results.

Collect blood in serum separator tubes.

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 or  with freezer packs.

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.

For additional guidance on the transport of infectious substances in other languages, please click on the link below.

http://www.who.int/ihr/capacity-strengthening/infectious-substances/en/

Appropriate clinical symptoms with potential exposure to Ornithodoros spp.ticks. Tick-borne relapsing fever (TBRF) is characterized by recurring febrile episodes that last ~3 days and are separated by afebrile periods of ~7 days duration. During the febrile episode, patients develop very high fever (up to  41.5°C) and may become delirious, agitated, tachycardic and tachypneic. Duration is 10 to 30 minutes. This is followed by drenching sweats and a rapid decrease in body temperature during which patients may become transiently hypotensive. Along with fever, patients may experience a wide range of nonspecific symptoms including headache, myalgia, chills, nausea, arthralgia and vomiting

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 and travel history to western Canada and western-central United States. Acute serum should be taken within 7 days of symptom onset and convalescent serum should be taken at least 21 days after symptoms start. 

THIS TEST IS PERFORMED FOR INVESTIGATIONAL OR RESEARCH PURPOSES ONLY
 

In-house IFA.  This is a semi-quantitative test for the detection of IgG antibodies to B. hermsii.  A four-fold or greater increase in IgG titre between two serum samples drawn 1 to 2 weeks apart and tested in parallel is considered presumptive evidence of a recent or current infection with B. hermsii.  An IgG endpoint titre of greater than 1:64 alone should not be relied on for a diagnosis of infection with B. hermsii. Patiens with TBRF may have false-positive tests for Lyme disease because of the similarity of proteins between the two organisms.

Initiation of antibiotic treatment prior to testing may result in decreased antibody production which will affect the outcome of serological testing. However, if infection with B. hermsii is suspected based on clinical symptoms, treatment should be initiated.

30 calendar days.

1. Schaefer Badger, M. 2008. Tick talk: Unusually severe case of tick-borne relapsing fever with acute respiratory distress syndrome - Case report and review of the literature. Wild and Env Med. 19, 280-286.
2. Centers for Disease Control and Prevention. https://www.cdc.gov/relapsing-fever/clinicians/index.html