Diagnosis of Powassan virus infection.
This test should not be used as a screening procedure for the general population.
This test should not be used as a "test of cure."
This test should be used for patients with at least 7 days of symptoms consistent with Powassan virus (POWV) infection and exposure history.
Specimens positive for POWV may require confirmatory testing by a POWV neutralization assay.
For information see the following:
Enzyme-Linked Immunosorbent Assay (ELISA)
POWV
Powassan
Powassan virus
For information see the following:
Serum
For patients with less than 7 days of symptoms, the recommended testing is molecular analysis for detection of Powassan virus (POWV) RNA. Contact either a local Public Health Laboratory or the Centers for Disease Control and Prevention.
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.6 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
If not ordering electronically, complete, print, and send Infectious Disease Serology Test Request (T916) with the specimen.
0.5 mL
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Heat inactivated specimen | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 30 days |
Diagnosis of Powassan virus infection.
This test should not be used as a screening procedure for the general population.
This test should not be used as a "test of cure."
For information see the following:
Powassan virus (POWV) is an emerging tick-borne virus, harbored by Ixodes species ticks, which are the same ticks that transmit Lyme disease (Borrelia spp.), Babesia spp., and Anaplasma phagocytophilum, among other pathogens. POWV is a member of the Flavivirus genus, which includes other arthropod-borne viruses (arboviruses) such as West Nile virus and St. Louis encephalitis virus. Two lineages of POWV have been identified, sharing approximately 94% amino acid sequence identity, including Lineage 1, which is the prototypical POWV lineage transmitted by Ixodes marxi and Ixodes cookei, and Lineage 2, which includes deer tick virus and is transmitted by Ixodes scapularis. POWV is maintained in the environment in groundhogs, skunks, squirrels, and white footed mice. Unlike other tick-borne pathogens, following tick attachment to a host, POWV can be transmitted in as little as 15 minutes.
Following infection, the incubation period can last anywhere from 4 to 14 days, after which approximately 66% of patients will remain asymptomatic. Symptomatic patients may present with a nonspecific influenza-like illness, including high fever, fatigue, malaise, and myalgia. Approximately 30% of symptomatic patients will progress to develop neurologic manifestations, most commonly encephalitis. While some patients may recover, over 50% of individuals will have persistent neurologic sequelae. POWV has been associated with an overall mortality rate of 10%. Although there is no targeted antiviral therapy and treatment is entirely supportive care, diagnosis is important for a number of reasons, including the ability to discontinue empiric antibiotics and to provide prognostic information for patients and families.
Negative
Reference values apply to all ages.
Negative:
No antibodies to Powassan virus detected. Negative results may occur in samples collected too soon following infection, prior to the development of a robust immune response, or in immunocompromised patients.
Positive:
Antibodies to Powassan virus detected. Confirmatory testing through a local public health laboratory and/or the Centers for Disease Control and Prevention is recommended. False positive results may occur in patients with current or prior infection with other flaviviruses (West Nile virus, Zika virus, dengue virus, etc).
False-negative results may occur in severely immunosuppressed individuals who are unable to mount a detectable humoral immune response. False-negative results may also occur in samples collected too soon following infection (<7 days post-symptom onset).
False-positive results may occur in patients with prior or current infection with other flaviviruses. Contact your local public health laboratory to determine whether confirmatory testing via a neutralization assay is required or recommended.
This test should not be used as a "test of cure" as antibodies to Powassan virus (POWV) may persist for months to years after resolution of the infection.
This test should be ordered in patients with suspected, symptomatic disease who have had recent exposure to ticks in geographic regions endemic for POWV, including Minnesota, Wisconsin, and the northeast United States. POWV is also prevalent in ticks in Russia and certain regions of Asia.
False-positive results may occur in patients screened for POWV who are not at sufficient risk or do not have an exposure history to suggest infection.
1. Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Division of Vector-Borne Diseases (DVBD): Powassan virus disease. CDC; Updated January 10, 2019. Available at www.cdc.gov/ticks/tickbornediseases/powassan.html
2. Kemenesi G, Banyai K: Tick-borne Flaviviruses, with a focus on Powassan virus. Clinical Microbiology Reviews. 2019;32(1):e00106-00117
The test uses microtiter strips, each with 8 break-off reagent wells coated with recombinant Powassan virus antigens. In the first reaction step, diluted patient samples are incubated in the wells. In the case of positive samples, specific IgM (also IgA and IgG) antibodies will bind to the antigens. To detect the bound antibodies, a second incubation is carried out using an enzyme-labelled anti-human IgM (enzyme conjugate) catalyzing a color reaction.(Unpublished Mayo method)
Tuesday, Thursday
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
86790
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
POWV | Powassan Virus, IgM, ELISA, S | 29855-4 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
POWV | Powassan Virus, IgM, ELISA, S | 29855-4 |