STDs Detected by Blood Tests

Technician holding blood sample
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Among the number of reasons why people worry about getting an STD test is that they fear it will require embarrassing or uncomfortable swabs. But the good news is that thanks to significant improvements in testing technology, many STDs can be detected via an STD blood test or urine test.

Urine tests are primarily used to detect chlamydia and gonorrhea. Commercial STD blood tests are widely available for the following sexually transmitted diseases.

Herpes

There are a number of herpes blood tests on the market. That said, their accuracy is somewhat variable.

The downside of herpes blood tests is both HSV-1 and HSV-2 strains can infect the mouth and genitals. The blood test cannot determine the location of the infection in the absence of visible sores.

In addition, some doctors are reluctant to test for herpes in the absence of symptoms. They worry about the stigma associated with a positive test. They think that what people don't know won't hurt them.

The herpes virus can be transmitted even when no symptoms are present. That can lead to some painful conversations when a newly infected person thinks they've been lied to by the person they love. They may not believe that the person who infected them had no idea they had herpes.

HIV

HIV is usually diagnosed through a blood test. There are also oral tests that use saliva samples to test for the virus that causes AIDS. In general, it requires both a positive initial test and a positive confirmatory test for a person to be considered HIV-positive.

However, the process of confirmatory testing is usually invisible. Both tests are generally done on the same blood sample.

When you get your results, it doesn't necessarily show what tests were done on your blood. It only shows what the test results were in combination.

Syphilis

There are several different blood tests for syphilis. These are used in combination to determine whether you are currently infected. They can also determine whether you have ever been infected in the past.

Hepatitis B

As with syphilis, there are multiple blood tests for Hepatitis. These can be used to determine your history of infection. They can also determine whether you're currently infected with the virus.

Cultures

If neither urine nor a blood test is available for an STD, then it is usually identified by either visual or microscopic examination of sores or by some form of bacterial culture.

These types of tests may also be used instead of, or in addition to, blood tests for the diseases listed above in certain situations.

Taking cultures of herpes sores can be a more effective way to determine the virus location and specific strains than a blood test.

That's not true in all situations as the timing of testing is critical. But it can be a better choice if people visit their doctor early in an outbreak. 

The Use of Self-Swabs in STD Testing

If you’re worried about a swab test and need one, talk to your doctor. It’s possible that you may be able to take the swab yourself. That won’t fix the problem for everyone.

Self-swabs can be a big help for people who have histories of sexual trauma or those who are simply reluctant to have a stranger touch their body in what feels to them like an intimate way.

Not all doctors will allow people to do self-swabs, but they have been shown to be effective for detecting many STDs. If nothing else, it’s better to have a self-swab test than no test at all.

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