Ctfvigmmsmtser
This blood test detects IgM antibodies against Colorado tick fever virus to diagnose recent infection transmitted by ticks.
{"Detects IgM antibodies indicating recent Colorado tick fever infection","Performed on a blood serum sample","Positive result suggests current or recent viral infection","Symptoms include fever, headache, and muscle aches","Transmitted through tick bites, primarily in western United States"}
Key facts at a glance
- LOINC
- 109134-7
- Short code
- CTFV-IgM
- Synonyms
- CTFV IgM Msmt Ser
- Category
- cardiac
- Sample
- serum
- Container
- Serum separator tube (SST) or red top tube
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Enzyme-Linked Immunosorbent Assay (ELISA)
- CPT
- 86635
- SNOMED
- 371949004
- Specimen volume
- 1.0-2.0 mL of serum
- Stability
- Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days
- Hemolysis max
- 50
- Lipemia max
- 100
- Icterus max
- 20
- TAT
- 72–168 hours
- Order
- routine
What is this test?
The Colorado tick fever virus IgM antibody test is a blood test that looks for IgM antibodies against the Colorado tick fever virus in your serum. IgM antibodies are the first type of antibodies your immune system produces in response to a new infection, making this test useful for detecting recent or current infections.
How is the test performed?
A healthcare provider will draw a blood sample from a vein in your arm. The blood is then sent to a laboratory where it is processed to separate the serum (the liquid part of blood) from blood cells. The serum is tested for the presence of IgM antibodies specific to the Colorado tick fever virus.
What does a positive result mean?
A positive IgM result typically indicates that you have a recent or current infection with the Colorado tick fever virus. IgM antibodies usually appear within the first week of infection and may persist for several weeks to months. Your healthcare provider will interpret the result along with your symptoms and any other test findings.
What are the symptoms of Colorado tick fever?
Colorado tick fever is transmitted by the Rocky Mountain wood tick. Symptoms usually appear 3-6 days after a tick bite and may include: high fever, severe headache, chills, muscle aches, fatigue, and sometimes a rash. Most people recover within a few weeks, but complications can occur in some cases.
Reference range
Negative: < 1:10 titer; Equivocal: 1:10 to 1:20; Positive: > 1:20N/A
No special preparation required. Inform laboratory of recent tick exposure or travel to endemic areas (Rocky Mountain regions of the United States and Canada)
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
Do I need to fast before this test?
How long does it take to get results?
What should I do if my test is positive?
Can I get Colorado tick fever more than once?
How can I prevent Colorado tick fever?
Sources
- 1
- 2
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 14, 2026. · Read our editorial policy