Herpes is a lifelong infection, but Lauren had it only for six tumultuous months. Or rather, she believed she did, after a request for sexually transmitted disease testing returned a positive result. But after weeks of Googling, chatting with members of online herpes forums, and reading scientific papers, she asked for a different test, which eventually confirmed her suspicion — her herpes diagnosis was wrong.

In the six months that passed between the tests, the mistake led her to keep a romance at bay and left her anxiously patrolling her health.“Every tingle I would get in my leg or any kind of itch down there would just set me off,” sending her into a new flurry of research, she said. “And that was just to try to calm my own anxiety, but it would only really make it worse.”

Genital herpes, predominantly caused by herpes simplex virus type 2, is a sexually transmitted disease that’s very common — 1 in 6 people aged 14 to 49 in the United States have HSV-2, and this number goes up with age. Most of these people, however, don’t have obvious symptoms and wouldn’t know they were carriers without blood tests.

But blood tests can be highly unreliable. The kind of test used to diagnose Lauren, an IgM test, has long been rejected by the Centers for Disease Control and Prevention but is still used by some clinicians. Meanwhile, the CDC and the US Preventive Services Task Force concur that the most widely available herpes test, called HerpeSelect, should not be used to screen asymptomatic people because of its high risk of false positives: Up to 1 in 2 positive tests could be false, according to the USPSTF’s most recent guidelines.

That high failure rate isn’t, however, always communicated to patients. Online forums abound with stories like Lauren’s, of people who request herpes tests alongside those of other STDs and are shellshocked by the results. Some doctors discourage the testing or simply don’t include it in a standard STD panel without having the conversation. But no data exists on herpes screening rates, according to Kimberly Workowski, lead author of the CDC’s STD treatment guidelines — so it’s difficult to say how many people could be living with the misdiagnosis.

Herpes simplex
A micrograph of herpes simplex virus in a Tzanck test specimen. CDC

Testing pitfalls

Next to the meandering waterways connecting Puget Sound to Seattle’s Lake Washington is the only laboratory in the world that offers to the public the Western blot, the gold standard test for herpes. The University of Washington Clinical Virology Laboratory provides the test to patients across the country, a practice it began over a decade ago when it realized the more common tests were prone to false positives.

The problem, said Christine Johnston, a physician and researcher at the lab, is “low-positive” results of antibodies to HSV-2. The cutoff for a positive result on the HerpeSelect test, manufactured by Quest Diagnostics, is 1.1. A 2005 study published in the journal BioMed Central Infectious Disease found that index values above 3.5 yielded over 90 percent accuracy — but scores between 1.1 and 3.5 had around a 50 percent chance of being wrong.

What’s more, scores falling just above the 1.1 cutoff had an almost 90 percent chance of being wrong.

When tests fall between 1.1 and 3.5, more testing is necessary, said Johnston. This recommendation is also noted in the 2015 CDC Sexually Transmitted Diseases Treatment Guidelines. But some patients will never be referred for a second test.

“I think most clinicians are unaware and perhaps labs don’t have this available and/or it is not straightforward to order,” Johnston said of second-step tests.

But while her facility’s Western blot is considered highly accurate, it is expensive and cumbersome to perform. Each test costs over $200 and the University of Washington is the only lab that provides it.

Other confirmatory tests also exist, for instance Biokit’s HSV-2 Rapid Test and Quest’s own HSV-2 IgG Inhibition assay. The latter, which adds only $4 to the price of the HerpeSelect test, performed well in a study conducted over a decade ago. Rick Pesano, the medical director for infectious disease at Quest, believes that with more awareness, the test could stand in for the Western blot. But the test was not mentioned in the USPSTF guidelines because it still has not been evaluated in asymptomatic individuals, according to Cindy Feltner, associate director of the RTI-UNC Evidence-based Practice Center, who helped prepare the science review for USPSTF.

“We need better diagnostic testing. That is where we are stuck at this point,” said Johnston. “We don’t have a good test that’s inexpensive, high throughput, and reliable.”

Finding out the hard way

No good data exist on how often patients with questionable positive results are actually re-tested. Until the 2015 update, CDC herpes testing guidelines had no mention of confirmatory testing for low-positive results, said Johnston. So patients often discovered the option not through their doctors, but through searching the web and reading online herpes forums.

That was the experience of Bryan, a 40-year-old man who lives in Indiana, who wrongly believed he had herpes for about two months in 2011. The misunderstanding actually put him at higher risk, he said: During those months he considered joining the hundreds of thousands of Americans on dating sites for herpes-positive people. Exclusively dating people with herpes would have increased his likelihood of contracting the virus.


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The experience of YT, a 33-year-old mom who has suffered from frequent herpes symptoms over the last year, shows another side of the testing breakdown. She believes she was given HSV by a partner who didn’t realize herpes wasn’t included in his previous STD tests, she told STAT. Having herpes has caused her significant emotional trauma, and has driven her to permanently swear off dating. Had her partner known his true status, she wonders if her story would have been different.

These kinds of stories come out in anguished postings on internet forums and in dozens of confused calls to the UW lab each week, where research coordinator Matt Seymour says some desperate patients call over and over again, unable to get the answers they need from their doctors.

“People call and say, ‘I just don’t know what’s going on,’” he said. “We’ve almost become de facto counselors.”

Transmission electron microscope scan of cytomegalovirus particles. CDC

In the absence of answers

Herpes tests aren’t the only ones with a risk of false positive results. False positives can occur for any test that diagnoses viral infection based on antibodies, i.e., your body’s immune reaction, rather than direct detection of the virus. For similar diagnostics like HIV and hepatitis C testing, protocols automatically call for a second test that directly detects the virus whenever an antibody test comes back positive, said Paul Swenson, laboratory director in the department of public health of King County, Washington. Herpes, however, is a particularly challenging infection to directly test for, because the virus spends most of its time hiding in nerves. Swab tests can sometimes detect the virus during outbreaks, but this isn’t an option for people without symptoms. Thus even the Western blot relies on antibodies, and may give indeterminate results to a small number of people.

But two steps of antibody testing are still more reliable than one step; today’s diagnostics for Lyme disease and syphilis are a two-step antibody testing approach, said Dr. Edward Hook, a medical epidemiologist specializing in STI screening and prevention at the University of Alabama, Birmingham, who questioned why such a standardized two-step approach hasn’t taken firm hold for herpes.

“Some research has shown that two-step testing … might improve the specificity — that is avoid false positive results for the blood test — which would be a great thing because these diagnoses create great anxiety and concern for people,” he said. In a commentary accompanying the USPSTF guidelines, Hook expressed disappointment that herpes testing had barely improved over the past decade.

“There is no perfect test but there are ways to reduce the inaccuracies and reduce the number of equivocal results and those are actively used in other diseases,” he said in an interview with STAT. “But they haven’t been used very aggressively for the purpose of herpes.”

In the absence of sure-fire test advances, education and a lessening stigma surrounding herpes might help, not only by reducing test-related confusion, but potentially by bringing discussion of the virus out into the mainstream, said Hook.

“There’s no major herpes advocacy group,” he said. “People call attention to diseases that they suffer from, but people with herpes don’t feel they can call attention to it. And that creates a lot of suffering.”

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  • So basically my last BF had noticed a rash at first on his shaft and I had wondered about it but wasn’t really thinking wisely about it i suppose…anyways….we had stopped having sex for a little while and he would stay clean (taking a shower everyday, using sanitizer and washing his hands extra thoroughly) so as not to spread what was unknown that was going on with him at the moment. Anyways, I would stay checking up on him and how he felt like he was doing etc…he described it as a little bump to me and I did check it myself a few times and it literally looked like a rash really…he said he was never itchy and never experienced any pain or anything and that that was the only bump he had experienced and he said he had popped it and a little bit of pus had came out…anyways…it came a point and time where he was really ready to have sex again and I fell for it even though I should have went with my gut and told him “no”!!! 😭😭😭😭…I literally got so scared after we had sex that day and watched my bodies symptoms and everything!! And I read up online that HSV symptoms can start in as little as 2 days after contacting the virus…well…gues what?!…a whopping 2exact days later I felt something that start to hurt in my labia, and after all of my research I knew what it had to be!! I was scared for my life and still feel like my life is over right now and I’m not even with this boy anymore…he was suppose to get tested but we had broke up before that could even happen so I don’t even know if that’s really what he had…but how could I contract something a whole exact 2 days later and I was in so much pain…could barely walk and/or sit and even sleep…Anyways, needles to say, I went to the doctors and they said it looked like herpes…I was pissed, but they also told me I had a complicated yeast infection too…so who knows how long I had that and I know when you get a compkicated one it can create sores so I don’t know…anyways they told me I had that and that I had HSV but she couldn’t prescribe me any medication until my results came back, but they did prescribe me medication for my yeast infection I did take my yeast infection medicine and bam! A day later my other symptoms weee gone!! And then though a week later I got my HSV results back and they said I tested positive!! But only at a 1.9 and I know that number can be prone to be a false positive…went to a different location a few weeks later to take another blood test and they just sent it to a different lab and and it also came back positive, but I forgot to ask at what rate this one came back positive as because I was still so disgusted with myself…anyways I still don’t know what my EX had or anything or even if my results are really true and I am just scared and I can’t have herpes like my symptoms aren’t really making sense anyways…

  • Please let me share our story. My nineteen year old son became very upset when a classmate of his said he gave him impetigo. She spoke of it as a STD. To settle the matter, his doctor ran the entire series of STD’s and included HSV 1 and HSV 2, more because I knew HSV was not normally tested for. We were devastated when both returned positive. He gave my “son” the talk. I was suspicious about the low numbers. We went back to his chief nurse who assured us it was a correct diagnosis. I researched, called health departments, the CDC, etc. The Western Blot kept coming up. I read and read. Terri Warren, with the Westover Heights Clinic said his 1.42 and 1.48, HSV 1 & 2, respectively, fell well within the possible false positive range ,about 1.0 – 3.0 range I believe. But the University of Washington’s designated blood drawer, AnyLabTestNow, would not return my calls (Daphne, AL) or had not heard of a Western Blot (Pensacola, FL). I no longer trusted LabCorp , nor the lab workers at the doctor’s office. I called and visited the lab at our local hospital. They did not want to do it but did. My doctor had never heard of a Western Blot. When I insisted he give me the referral to UW’s Virology Lab, he did know what a N P C code was. ( That’s his national code number, so to speak). My Point — If you are in a possible false positive range, go to a better lab. Don’t hesitate to do your homework. Go to a specialist if the GO seems out-of-date. Fight.

  • I was recently told I was positive for hsv2 I am so distraught at this time and paranoid I don’t know where to turn what should I do

    • Get a second test from a different lab before you do anything. I was tested with a false positive from one lab and tested negative at 3 other labs

  • I had a very similar experience. I tested positive through a blood test despite never having had any signs or symptoms. The doctor was basically like, ‘welp…sucks for you!’. However, after doing research I was incredulous to find how often these tests are inaccurate. The University of Washington does a Western Blot test, the only lab in the country that does it I believe. It is the gold standard for this kind of testing. I got a second test done this way and it came back completely negative. I even went to the contagious virus specialist at the medical group and they were surprisingly ignorant about the Western Blot. My doctors would have let me go my entire life believing that I had this virus. http://depts.washington.edu/rspvirus/ Call them, they are 10 times friendlier and more helpful than my doctors office ever was.

    • How you were able to have the western bolt test done? Did you go to the lab directly in Washington?

    • If you call the University of Washington, they will send you a kit with the proper packaging and labels to ship a blood sample to them. My doctors office did not make it easy and was pretty dick about it, but I eventually got them to take my blood, give it back to me and then I had to shipped it to the University of Washington.

  • Hello, I’ve been diagnosed with hsv 1&2 after getting a full STD check through blood screening. I have no symptoms nor have I ever had any,along with my doctor never encouraging me to come in and discuss treatment and/or have a second test done to verify my results!! I have only one partner who got tested a day after my results who has never had any signs or symptoms as well and we are both terrified! A little advice on how to deal with my situation and get a test with the most accurate results? It’s only been 4 days since I was diagnosed and emotionality I’m so exhausted I’m unable to eat and interact with anyone because of how worried iam. Any advice would help?

  • Hello!
    I have only had one sexual partner in my life. 2 months into our relationship my boyfriend had a very bad sore in his genital area. He said his dog jumped on him when he had no pants on and then it got infected. I told Him to go see a doctor, which he did. His doctor was testing him for herpes. He texted me accusing me of cheating on him. I was so mad and confused I went to a testing center and my tests came back positive for hsv 2. When he and I talked after his tests came back he was negative. They did his blood, urine, and Swab. They all came back negative. Could my test be wrong? I’ve been depressed and beating myself up for weeks. Plus he dumped me so that’s great. Please help!

  • I received a positive test on the HerpeSelect testing with a 2.14 having no symptoms during a routine check up. I immediately began taking medication. Thanks to this article and other research online I discovered the Western Blot test through U of Washington and requested this test with my doctor. I received the results back from the Western Blot test and I am negative for either hsv1 and hsv2. I highly recommend others follow up on testing to avoid the negative emotional effects and unnecessary medication because of a false positive. Thank you soo much Lindzi for publishing this article and helping me!

  • Good Morning all,

    I had a case of chicken pox when I was a child. I recently tested positive for HSV 1 & 2 but have never had an outbreak. I don’t know what to do none of previous partners have it. I am however scared confused and lonely. I need HELP understanding it all. Both of my reference range shows negative but results are positive.

    Comments: Negative – No detectable antibody, susceptible to infection. Equivocal- Indeterminate, submit another specimen. Positive – IgG Antibody present; suggests previous or current infection. Effective March 26, 2004, to more accurately differentiate HSV-1 from HSV-2 antibodies, these tests are performed using recombinant glycoprotein G type specific test kits for the detection of IgG antibodies to HSV-1 and HSV-2. Glycoprotein G is the only major HSV protein to elicit responses that are primarily type specific: gG1 elicits HSV-1 antibodies, and gG2 elicits HSV-2 antibodies. Both HSV-1 and HSV-2 can cause genital herpes infection.

    I was tested in Aug of 2004 upon entering into the military and it was determine that I was immune to Varicella Zoster Virus Ab.

    Just trying to make sense of it.

  • I was tested positive for HSV-2 I want to get tested again but I don’t know want to do I’m lost scared confused and assumed i don’t know who to talk too

  • I was diagnosed with virus after broken back in 1990… Then diagnosed with cold on my spine in 2001 and Molleretts Menengitus 3 times caused by hsv in summer 2005.
    Both issues reoccurring regularly since….very sick. Debilitating
    Now 2018 I have been told I do not have virus at all!!!
    Rash present Dr felt no reason to test because I have no virus?
    Multiple test. Lumbar punctures. From different drs at different facilities. Over 20 plus year span.
    Dr says all false positive or my body just got rid of virus.
    How is this possible and what am I supposed to think or do?
    Completely confused tramatized and angry!!!

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