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.”

Herpes
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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  • Just wanted to post this because of the unnecessary stress caused by the cheap STD test I took at a walk in clinic and maybe I can spare some people the stress… I went to the clinic to get my test done for the whole list of possible STD’s (ironically to be able to show my female friend with benefits a clean chit for her peace of mind). The following week, I got my results online and they showed I negative on all non HSV STD’s but was massively positive for HSV-1 (score of 47.6!) and slightly positive for HSV-2 (score of 1.7). It caused a lot of stress for us and basically put us on hiatus until later when this was resolved. I wasn’t worried about the HSV-1. I knew I had it as I had a cold sore in the past and HSV-1 is arguably not even an STD. I was really worried about the HSV-2 though even though I never had any symptoms. After doing lots of research, I spent a significant amount of money to get the Western Blot HSV-2 test done at the University of Washington. The kit was free but the analysis was around 250$ and the high speed refrigerated shipping was another 90$. After a stressful 2 weeks, I got the results back that I absolutely did not have HSV-2. I personally know a couple friends that are trusting their results from the cheaper HSV-2 test and assume they actually have it even though they also have no symptoms. I know now that if you really want to know for sure, you have to spend the money and get the better test done.

  • I woke up with a bump lip on sunday and i went to the doctor on monday morning. I got tested and the results came negative (IgM HSV-1) negative. Then on Tuesday i went to planned parenthood got a blood work done test again, it came out positive (HSV-1 IgG) i feel like my world is tumbling down to pieces… im so sad my life is over.

    • 80 % people have hsv 1 oral this is not a worry, maybe u will never c that on the lip in your entire life don’t worry about it relax its not big deal

  • I need some guidance, I went into my local urgent care for testing because I cut myself near my vaginia lips while shaving and it started to hurt. The doctor did testing for everything, hiv aids and all the sti’s and hvs 1&2. She did urine, blood test and the culture swab on my cut. Well when she first called me she said everything was negative but HSV 1&2 were positive. I was devestated to say the least. One day later, she calls back and says the hvs 1 was actually negative but I do have 2. Well, I requested my lab results so I can follow up with my doctor, mind you she never gave me meds. Well the lab results say positive abnormal got hsv 2 with 1.62. However the culture swab is completely negative. I’m confused now do I have hsv or no? The lap paper also says to retest in 2-4 weeks. Helppppp

    • Swab test must be done 48 h after outbreak start, to be precise, blod tests are not reliable that much they can have 25 % false positive, she perform Igg test it can separate 1 from 2, it can be false positive some conditions in body can lead to some scores that is in range of positives doesn’t mean that couse by hsv.. So check ur self red areas, blisters that burning sensation while urinate and so on just don’t panic if u don’t have much symthoms wait 4 weeks than go to test again and change ur doc it’s always better to hear one more opinion I hope u are false positive

    • If you want to know for sure, request the Western Blot HSV2 Test from University of Washington. Between getting the blood drawn, paying the lab fee, and the shipping, it will set you back about 400$ but it was worth it for me to find out I was negative for sure.

  • Is anybody know something about those measurements Au per ml can’t find nowhere for hsv recently I get tested so I come up negative for igm but igg positive with some kind of number 29.6 au/ml don’t know is that high or low also the test doesn’t show which type is it only this can someone have explanation on this by the way I didn’t have blisters I had like balanitis on penis urethral inflammation also bladder after few days they found enterococus also faecalis in my urine my balanitis was present over a month :s

  • I have same situation i dont have any outbreaks or symptoms. My bf ask me to take a test if i have any disease like Hepa, Chlamydia, Syphillis, Gonnorrhae, HIV and Herpes. So when I found out the result just only one is reactive that is Herpes (herpes simplex virus) say herpes simplex virus igg detected.I call my doctor again to ask a specific type of HSV but the result is the same Reactive but the problem is i dont know which of Hsv 1 or hsv 2 is positive it didnt say in the report form. I dont have any outbreak.

  • 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.

    • You don’t have herpes people just don’t like you your readings even say below the limit to even have it research the readings again the readings are the numbers you got!!

  • 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.

    • There is so much on false positive yet no one talks about antibodies, if one has antibodies for hsv-2 doesn’t one have herpes 2?? I mean wouldn’t this make it simple for people to know if they have hsv-2? I just want to know because I have 1.07 IGG , can someone anyone clarify ?

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