Is tick testing accurate?
Testing a tick for pathogens is something that people stumble across when searching for advice after finding a tick, or they might get a recommendation from a friend or family member. They may not have access to advice from a healthcare provider or similar trusted source, and are left to sort out conflicting information on their own.
Common arguments against tick testing:
The CDC warns, and this caveat is amplified by many health practitioners, that tick testing laboratories “are not required to have the same high standards of quality control used by clinical diagnostic laboratories.” We addressed—and reinforced—most of the CDC’s concerns about tick testing (especially how tick testing results should not be confused with a diagnosis) in an earlier post, but this is a good point to address separately.
Tick testing labs are not regulated in the same way that diagnostic labs are, because the FDA and similar agencies have not established guidelines and oversight mechanisms to do so. That doesn’t mean that the work done in a tick testing lab cannot match or exceed the requirements of CLIA or similar compliance. The burden of quality assurance and transparency falls on individual labs, and this duty is one that we have taken very seriously since TickReport’s founding in 2006.
Tick testing vs. diagnostic testing
Another area of concern stems from confusion between tick testing and diagnostic testing (typically, examining a blood sample for the presence of antibodies). Concerns about the accuracy and sensitivity of 2-tiered Lyme disease antibodies have been raised for many years. MedZu Labs and the TickReport service do not study diagnosis or treatment directly, so this post will not dissect that issue in any depth; interested readers can learn more about this debate from Global Lyme Alliance HERE. Some of the key questions about Lyme diagnostic testing are 1) are Lyme tests comprehensive enough to detect antibodies produced in response to different strains of Lyme bacteria, and 2) are those tests sensitive enough to detect minute antibody traces contained in a small blood sample.
Neither of these concerns applies directly to tick pathogen testing. Here’s why:
Tick testing using qPCR assays detects the DNA or RNA of a disease-causing microbe directly, rather than searching for the type and concentration of antibodies that a “typical” immune system is expected to produce. That direct testing allows extremely specific targeting of DNA/RNA fragments that are unique to a specific organism, and careful labs can design overlapping and complementary assays to ensure that no variants are overlooked.
Tick testing will test the entire tick by grinding it up and homogenizing the extracted nucleic acids (DNA + RNA). Combined with the extreme sensitivity of qPCR testing, this ensures that any traces of pathogen in the tick can be detected with a properly-designed assay.
Can tick testing labs be trusted?
qPCR testing is an incredibly sensitive and specific tool, and is an extremely accurate way to answer a molecular biology question. The reliability of qPCR results then depends on the research and expertise that went into designing that question. Careful work with as many positive and negative controls as possible goes into validating a molecular assay; inexperienced labs and student projects can sometimes take off-the-shelf products at face value. The bad data that result can be harmful to scientific understanding in general if those data are published without appropriate review processes, but the stakes are even higher when an individual sends their tick for testing and may use those results as one part of a clinical diagnosis in conversation with their doctor.
TickReport assays draw on a combination of published and proven sequence targets as well as novel sequencing of known samples. Before a new assay is introduced as part of TickReport’s menu offerings, it has typically been applied to between 10,000 and 50,000 known positive and negative samples to ensure accuracy and specificity of the DNA or RNA targets. Most of those pathogen assays have also been published in peer-reviewed journals, and we know that they have formed the basis or a benchmark comparison for multiple academic and state testing labs. (*Stay tuned for a new page with sources and commentary on some of our most important publications).
What tick testing lab should I choose?
In recent years, a few labs across the country have attempted to replicate the TickReport model, and the decision between labs is more complicated than ever. Tick testing services can vary in the comprehensiveness of testing, turnaround time, location of labs, follow-up resources, and general reputation for accuracy and communication. Every person who encounters a tick has a tough decision to make, but the TickReport lab can offer:
The most comprehensive testing menu for tick-borne pathogens confirmed to be present in North America, Europe, and parts of Asia.
The fastest turnaround time, with most results reported in about one day after arrival, and every result guaranteed within three business days of arrival.
Follow-up communication about your results and advice about testing whether you tested a tick last week, last year, or are just looking to learn more about the risks ticks pose. Education is a key part of our mission, and our experts are passionate about evidence-based methods that remain open to emerging infections or anomalous cases.
The chance to contribute to public health research in your community. Anonymized results from every tick we test are posted in real time to our Passive Surveillance Database (or more simply, our “Stats Page”) webpage and are searchable by location or type of tick.
If you are bitten by a tick during the winter or any other time of year, visit TickReport.com to arrange identification and testing for over 20 different tick-borne pathogens.