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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.

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.”

  • So I got tested originally because a one night stand texted me saying she had a bump resembling genital herpes. Both were negative and at that time my herpes one was at .6

    I recently got tested due to having a small paper cut like scratch below the head of my penis. My herpes two remained negative and low but my herpes one tested at 1.0. Is it possible I have herpes one on my penis or am I testing a false positive or just test high.

    I had mild to low cold like symptoms during my blood test. I haven’t had any other major symptoms. Just below the tip of my penis like under the head looked a bit dry and red multiple times but no bumps or sores. My doctor told me he thinks it’s a skin issue for the dermatologist. Any advice ?

  • What is wrong with you people? You act worried and then don’t respond. Do your own tests indicate genital herpes? These numbers are clearly NOT indicative of herpes. But I don’t want to sound harsh. My son’s nurse swore he had herpes, but I knew the numbers were too low. We used the University of Washington. Sure enough, his (was it 4.ish?) was/were false positive. However, I don’t think he will ever truly believe it again.

  • Good day,

    I would really like some assistance with an anomaly I am experiencing.

    I test for HSV Type 2 in July and my results cam back negative , the first time the IGm came back borderline and the test was redone which came back negative.

    Last week Monday i wasn’t feeling well , i have been getting flu like symptoms which include

    1) Fever only on evenings (very mild not much of a temperature), loss of appetite, feeling tired but not extremely, no motivation to to exercise etc. In the mornings i will feel fine but evenings I get the fever / flu symptoms.

    2) I also had a slight non persistent itch in my groin area , it would itch but subside in a few secs.

    3) My hands would be dry and a bit itchy , under my feet would be dry , itchy and reddish.

    4) My mouth would feel dry and my lips would be dry also , I get a dehydrated feeling.

    On Friday on that week I noticed a small cut on my lower lip resembling a tear. After searching google I started to get anxiety and also panic, this lead me to rush to get a HSV 1 &2 blood test done. That same evening the result were emailed to me and all my results said positive with readings as follows.

    Herpes 1 IGG 1.15
    Herpes 1 IGM 1.25
    Herpes 2 IGG 1.14
    Herpes 2 IGM 1.26

    After getting these results I went into a serious depression, couldn’t sleep , eat and even had dark thoughts. I was confused as to how my results showed negative just weeks ago and now it’s positive.

    The last interaction sexually was in June 15th. It involved no penetration she sat on my lap with my pants on , we kissed not so for long , I fingered her and she jerked me off ( Is it possible after fingering her and then touching my penis I contracted it?)

    I did the test in July 16 , was it too soon that is why I got a negative result? I am very worried and concerned. ever since i have been getting this flu like symptoms and loss of appetite etc I have been searching my entire body for signs of outbreaks , lesions , bumps, fluid filled sores but this is day 9 and I haven’t seen any and trust me I have been checking with a flash light and magnifying glass . My lymph nodes haven’t been inflamed or hurting either.

    Is it possible I am one of those that don’t have Symptoms ?
    Is it possible I have it and just not having any outbreaks?
    Can my results be false positive due to the flu ?

    Any assistance would be greatly appreciated , shed some light on this as I can’t manage.

    Thanks in advance.

  • Only today I got my reports and according to the numbers HSV (1+2) IgG < 0.500 and IgM is 1.15. I was in a monogamous sexual relationship and it ended in feb 2019 and after that I haven't been sexually involved. The first time I found a genital rash was in the month of May. I thought it was a fungal infection as it was gone the very next day. But it kept coming back from time to time and then I visited a urologist who advised me go through HSV screening. I will visit the doctor tomorrow to show him the reports. I have also asked my only (ex) sexual partner (who has no symptoms at all) to get tested. I don't know if it's false positive or not. I am having so much trouble digesting it, I know it is not fatal, but I am not being dramatic when I say that my anxiety has increased ever since I read the reports and I have no one to talk to.

  • I was tested at local VA- the test was done by Quest Diagnostics. The results came back POSITIVE with Ref: Range : NEGATIVE. There were no ref range numbers. I took a second test about a month later HSV 1 and HSV 2 IGG AB same as the first test with the same results—however Quest performed a HSV and HSV2 DNA using same blood used for the IGG. The results were not detected and Ref. Range not detected———does anyone know what this means?

  • I was diagnosed with Hsv2 by swabbing 10 years ago. I have never had ANY symptoms and dont take medicine. My partner has always tested negative so a few months ago I took a blood test and everything came back negative. My doctor said the swab was most likely a false positive.

    • How can we be accurately diagnosed? Are there additional testing that was recommended to you? My blood test have been negative as well. I’m worried about neonatal transmission now that I’m pregnant.

  • The Quest Herpeselect test should really be pulled off the market. I have had the test several times with it coming back with numbers just barely over 1.0 being listed as positive. Following up with other tests, have always come back negative. Even knowing this process now, it is still devastating each and every time and as other comments have indicated, physicians are not very familiar about the false positives. I had to educate a previous physician about this issue and about the options for follow up testing. If you are in this situation, ask for a follow up test using a different method and also lookup the Western Blot test option for confirmation. Quest should be held accountable for continuing to use a test that has been shown to have these kinds of issues

  • How accurate is a swab? I was diagnosed 4-5 years ago by a swab. I was put on acyclovir, and I’ve taken it ever since. However, I’ve not had any more outbreaks since?

    • I just got my results back through a swab done on me and it came back positive, I am also on acyclovir. I am questioning the same, with my anxiety going crazy researching every single day if this is truly what I have. How accurate is a swab and what other tests can be done!!!!

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