Yes, there are several types of herpes tests available, ranging from swabs of active sores to blood tests that detect past infection. The right test depends on whether you currently have symptoms. If you have a visible sore or blister, a swab test is the most accurate option. If you don’t have symptoms but want to know your status, a type-specific blood test can tell you whether you’ve been exposed to HSV-1, HSV-2, or both.
Swab Tests: The Most Accurate Option During an Outbreak
When you have an active sore, blister, or ulcer, a healthcare provider can swab the lesion and send the sample to a lab. Two methods are used to analyze swab samples: viral culture and PCR (a DNA-based detection method). PCR is far more reliable. In a head-to-head comparison published in the Journal of Clinical Microbiology, PCR detected the virus in 100% of positive samples, while culture caught only 50%. Most labs now use PCR as the standard approach.
Swab testing works best when the sore is fresh and hasn’t begun to crust over. The earlier in an outbreak you get swabbed, the higher the chance of an accurate result. A swab test also tells you which type of herpes you have, HSV-1 or HSV-2, which can be useful for understanding your risk of future outbreaks and transmission.
Blood Tests for Herpes Without Symptoms
If you don’t have an active sore, a blood test is the main option. These tests don’t look for the virus itself. Instead, they detect antibodies your immune system produces after infection. A type-specific IgG blood test identifies antibodies to a unique protein on the surface of each virus type, allowing the lab to distinguish between HSV-1 and HSV-2 separately.
There’s an important timing consideration. Your body needs time to build detectable antibodies after exposure. Most experts recommend waiting at least 12 weeks after a potential exposure before getting a blood test. Testing too early can produce a false negative simply because your immune system hasn’t generated enough antibodies yet.
Labcorp offers a combined HSV-1 and HSV-2 antibody test for $149 without insurance through its direct-to-consumer platform. Pricing at other labs and clinics varies, and many insurance plans cover the test when a provider orders it for a clinical reason.
Why the CDC Doesn’t Recommend Routine Screening
This surprises many people: the CDC does not recommend herpes blood testing for people without symptoms in most situations. The reason comes down to accuracy. Blood tests for HSV-2 can produce false positive results, particularly when the test score falls in a low-positive range just above the cutoff. The FDA has specifically warned that false reactive results are more likely in people at low risk of infection and in those with borderline scores.
A false positive herpes diagnosis carries real psychological weight and can affect relationships, so the CDC’s position is that testing people without symptoms creates more harm than benefit in most cases. Testing is generally recommended when you have symptoms, when a sexual partner has herpes, or when you want a comprehensive STI panel for a specific clinical reason.
Avoid IgM Testing
Some labs and clinics still offer an IgM blood test for herpes. This test is not recommended for clinical use. IgM antibodies are supposed to signal a recent infection, but in practice the test is unreliable. It cross-reacts with other herpes-family viruses (like the ones that cause chickenpox and mono), producing misleading results. If a provider offers you an IgM test for herpes, ask for a type-specific IgG test instead.
What to Do With a Low-Positive Result
If your IgG blood test comes back positive but the index value is low (close to the cutoff threshold), there’s a meaningful chance it’s a false positive. In this situation, confirmatory testing is available. The gold standard is the HSV Western Blot, developed at the University of Washington. This test separates viral proteins and checks whether your blood reacts to them in a pattern consistent with true infection. It reports HSV-1 and HSV-2 results independently as positive, negative, or indeterminate.
The Western Blot is not available at standard commercial labs. Your provider needs to send the sample to the University of Washington’s lab specifically. It hasn’t gone through FDA clearance, but it’s widely considered the most accurate herpes blood test available and is the go-to option when standard results are uncertain.
At-Home Test Kits
Several companies sell herpes test kits that you can order online or buy at a pharmacy. These kits typically involve a finger-prick blood sample or an oral/genital swab that you collect yourself and mail to a lab. The lab analysis itself uses the same technology as clinical tests, so the methodology is sound.
The weak link is sample collection. Accuracy depends heavily on collecting a good sample, and without a trained professional guiding the process, errors are more likely. There’s also less oversight of some direct-to-consumer labs compared to hospital or public health department laboratories. If you go this route, look for a service that uses a well-known reference lab and offers access to a clinician to discuss your results.
Which Test Is Right for You
- Active sore or blister: Get a PCR swab test as soon as possible, ideally before the sore starts healing. This is the most accurate test available.
- No symptoms, recent exposure: Wait at least 12 weeks, then get a type-specific IgG blood test. Testing earlier risks a false negative.
- No symptoms, no known exposure: Routine screening isn’t recommended by the CDC for most people. Talk to a provider about whether testing makes sense for your situation.
- Low-positive blood test result: Request confirmatory testing with the University of Washington Western Blot before accepting the diagnosis.