Sage-Tips

Can a blood test tell the difference between HSV-1 and HSV-2?

Blood tests that detect antibodies to HSV can distinguish between HSV-1 and HSV-2 but not the site of infection. This means that blood tests cannot tell whether a patient has a genital or oral herpes infection.

What test can give me an answer if I have HSV-1 or HSV-2?

Polymerase chain reaction (PCR) test. This test can tell the difference between HSV-1 and HSV-2. Using the PCR test on skin sores isn’t common. PCR is used mainly for testing spinal fluid in rare cases when herpes may have caused an infection in or around the brain.

Can you be diagnosed with HSV-1 and 2?

HSV-1 is mainly transmitted by oral-to-oral contact to cause oral herpes (which can include symptoms known as “cold sores”), but can also cause genital herpes. HSV-2 is a sexually transmitted infection that causes genital herpes. Both HSV-1 and HSV-2 infections are lifelong.

Does HSV-1 and 2 have the same antibodies?

There are two possible antibodies that your body can make to HSV-1 and HSV-2. These are IgM and IgG. IgM is the antibody that is made first and typically represents a current or acute infection, although this may not always be the case.

Can you test negative for HSV-1 and still have it?

A negative (normal) test most often means you have not been infected with HSV-1 or HSV-2. If the infection occurred very recently (within a few weeks to 3 months), the test may be negative, but you may still be infected. This is called a false negative.

How accurate is the HSV culture test?

The herpes culture test (swab test) has a 0\% chance of a false-positive test result. This means that a person who tests positive can be 100\% sure that they have the herpes infection. The commercially available herpes IgG test (HerpeSelect) has up to a 19\% probability of revealing false-positive test results.

How common is HSV-1 antibodies?

About 70\% of adults have been infected by HSV-1 and have antibodies against the virus. About 20 to 50\% of adults will have antibodies against the HSV-2 virus, which causes genital herpes.

How accurate is hsv1 blood test?

Herpes blood tests have a sensitivity level of about 80-98\%. This type of test detects antibodies to the herpes virus, so it may not be as accurate when performed soon after infection.

Can you get a false negative HSV-2 test?

However, there’s a small chance of getting an HSV-1 genital infection and the test cannot distinguish where the infection is located. False negatives are not common with this type of test, but there’s still a chance that a negative result for HSV-1 or HSV-2 may not be accurate depending on the timing of your exposure.

Can a HSV culture be wrong?

Herpes tests can be wrong, but it is much more common for them to give a false negative (because we are swabbing a herpes sore that is already healing up), than for the test to give a false positive. It sounds like in your case you did have an active sore when you got tested, and the swab found HSV-1 in the sore.