Herpes Simplex Virus -1 and -2 Past Infection Blood Test, from our experts to you.Dr Sam Rodgers MBBS, MRCGP
Chief Medical Officer
What can I learn from this test?
What is herpes?
What’s the difference between HSV-1 and HSV-2?
Limitations of this test
How to prepare for your test
Frequently asked questions
How accurate is the Herpes Simplex Virus-1 and -2 Past Infection Blood Test?
Provided the test is taken correctly, our Herpes Simplex Virus-1 and -2 Past Infection Blood Test is very accurate. Based on studies carried out by the assay manufacturer, this test was able to correctly detect all samples where HSV-1 antibodies were present (23 out of 81 samples) and all samples where HSV-2 antibodies were present (21 out of 82 samples).
The ability of this test to accurately detect HSV antibodies (true-positives) is known as its sensitivity, while its ability to detect true-negative results is known as its specificity. So, the results of these studies correspond to a clinical sensitivity and specificity of 100%.
Even with highly accurate tests, it’s still possible to receive a false-positive or false-negative result.
What does genital herpes look like?
Genital herpes typically causes small blisters or sores around the genitals and anus. The blisters are usually red, swollen, and painful, and may burst to leave small, open sores or ulcers. If you notice any sores around your genitals, it’s important to attend a sexual health clinic as soon as you can.
Not everyone with genital herpes will have visible symptoms and the virus can still be transmitted even when sores aren’t present — this is known as asymptomatic shedding.
Can you get genital herpes from a cold sore?
Yes, it’s possible to contract genital herpes from a cold sore if there’s direct contact with a cold sore during oral sex. To reduce the risk of transmission, it’s important to avoid oral sex or close genital contact if you or your partner have an active cold sore.
Using condoms can also lower the risk, although it's not always 100% effective because herpes can be spread from skin-to-skin contact outside the area covered by the condom.
How common is genital herpes?
Genital herpes is a common condition in the UK. However, exact figures are difficult to determine since many people with the virus may not have symptoms or may not seek a medical diagnosis.
In 2022, there were nearly 25,000 new cases of genital herpes diagnosed in the UK, making up over 6% of all new STI diagnoses.
Who is most at risk of genital herpes?
Individuals most at risk of contracting genital herpes include:
-Women — women are almost twice as likely to contract genital herpes as men
-Young adults — peak incidence of HSV is in people aged 15–24
-People with multiple partners
-People who have unprotected sex
-Men who have sex with men (MSM)
-People with HIV or a weakened immune system
-People with a partner who has had previous genital herpes