Advantages and Accuracy of Rapid STI Tests

Rapid sexually transmitted infection (STI) tests have been designed to save people time, effort, and stress when being evaluated for gonorrhea, chlamydia, human immunodeficiency virus (HIV), and other infections passed through sexual contact. Some rapid STI tests are performed in a doctor's office or clinic, while others can be done in the comfort and privacy of your home.

These tests aim to avoid one of the most common problems seen at STI clinics: people who fail to return for their results. Oftentimes, a person will brave being tested only to back out when it's time to receive the news. As a result, an infection can be left untreated, increasing the risk of complications for the patient and the chance of the infection spreading to others.

Overcoming Barriers to Testing

A rapid STI test allows you to get your results in minutes rather than days. If the test is positive (meaning that you've been infected), you can get immediate treatment rather than having to come back to fill a prescription.

With diseases like HIV, this is important since early treatment translates to a lower risk of illness and a longer lifespan.

The newer tests also aim to overcome another factor that keeps many people away: needles and blood. Depending on the disease, a rapid test may only require a swab of body fluid or a urine sample (in addition to the traditional blood or finger-prick tests).

Accuracy of Rapid STI Tests

Not all rapid tests are created equal. Some have higher sensitivity and specificity than others.

Sensitivity is the ability of a test to correctly identify those with the disease (a true positive rate).

Specificity is a test's ability to correctly identify those who do not have the disease (a true negative rate).

When testing during acute infection, rapid STI tests offer the average sensitivity and specificity:

• Gonorrhea: 86% sensitivity and 97% specificity
• Syphilis: 85% sensitivity and 91% specificity
• Chlamydia: 86% sensitivity and 97% specificity
• Hepatitis B: 97% sensitivity and 99% specificity
• Human papillomavirus (HPV): 87% sensitivity and 94% specificity
• Herpes simplex: 93% sensitivity and 99.9% specificity
• HIV (at-home, oral swab): 92% sensitivity and 99% specificity

Unfortunately, a lower sensitivity rate translates to an increased risk of a false-negative result, meaning a person is told they do not have the infection when they actually are infected. For perspective, the 92% sensitivity rate of the currently available at-home HIV test translates to one false negative out of every 15 tests.

This is why certain bacterial diseases (like syphilis, gonorrhea, and chlamydia) are more accurately diagnosed with a culture rather than a rapid test.

A Word From Verywell

The failure rate of at-home tests is as much associated with product misuse (including improper swabbing and testing outside of the window period, when the infection exists, but it is too soon to be detected on a test) as the technical limitations of the tests themselves.

Neither the Centers for Disease Control and Prevention (CDC) nor the Infectious Diseases Society of America (IDSA) recommends rapid STI testing. It is for this reason that any positive, inconclusive, or suspicious negative result from an at-home test should be followed up with an in-office test at your local clinic or healthcare provider's office.