What are STDs?
Sexually transmitted diseases (STDs) are infections that can be transmitted through sexual activity and skin-to-skin contact. STDs are caused by bacteria, viruses, or parasites.
Approximately 20 millions new STD infections occur each year in the U.S. Half of all STD diagnoses occur in adolescents and young adults between the ages of 15 and 24 years.
The Role of STD Tests
STD tests are used to diagnose specific STDs. Tests may be part of a routine health screening or ordered when a patient experiences signs and symptoms of an STD.
Who should get testing?
Many people with STDs are asymptomatic or experience only mild symptoms of infection. Without testing, people infected with STDs may unknowingly spread the infection to others. STDs can lead to serious health complications, so appropriate STD screening and diagnosis is a major public health concern.
The goal of screening for STDs is to identify and treat people with infections before they develop complications and before they spread disease to others. Additionally, screening attempts to identify, test, and treat the sexual partners of people diagnosed with STDs to prevent continued spread of the infection.
While all sexually active people are at risk for STDs, not every person needs to be screened for each STD. STD screening focuses on people who are at a high risk of becoming infected due to factors such as age, gender, health history, amount of sexual partners, and sexual orientation. Doctors can assess an individual’s personal risk factors and determine the most appropriate testing strategy. Below is a brief overview of common STD screening recommendations:
- Adults and adolescents: Everyone from ages 13 to 64 should be tested for HIV at least once or more as needed based on risk level.
- Sexually active women: All sexually active women under 25 years old should be tested for gonorrhea and chlamydia at least every year. This recommendation also applies to women 25 years and older at an increased risk of STDs due to new or multiple sexual partners, or a partner who has been diagnosed with an STD.
- Pregnant women: During a pregnancy, women should be tested for syphilis, HIV, and hepatitis B. Pregnant women with additional risk factors should also be tested for chlamydia and gonorrhea.
- Sexually active gay and bisexual men: Men in this group should be tested at least once a year for syphilis, chlamydia, and gonorrhea. Men with multiple or anonymous partners should be tested more frequently, such as every 3 or 6 months. This group may also benefit from more frequent HIV testing.
- Unsafe sex and injectable drug users: Anyone who shares injection drug equipment or has sex without protection such as a condom should be tested for HIV at least once a year.
Getting test results
Patients may receive results of STD tests during a follow-up appointment with their doctor, over the phone, or though online medical charts. It’s important to discuss STD test results with a healthcare professional who can help you manage your risk for STDs and answer your questions about test results.
If STD test results are positive, it’s important to begin treatment as early as possible in order to reduce the chance of health complications.Your doctor can help you make a plan for sharing your results with sexual partners who may be infected and can discuss retesting that may be necessary after treatment is completed.
Types of STD Tests
There are over 20 types of STDs. STD testing may involve physical exams, oral swabs, urine tests, pap tests, and microscopic examination of fluid swabbed from a sore, the genitals, or the anus. Other STDs are diagnosed through blood tests. Here are some of the most common STD tests:
|Test Name||Test Sample||What It Measures|
|Chlamydia Testing||Vaginal swab, rectal swab, or urine sample||Detects the genetic material (DNA) of the bacteria|
|Gonorrhea Testing||Urine sample or swab from site of potential infection||Detects bacterial DNA|
|Hepatitis B Testing||Blood sample||Detects viral proteins (antigens), antibodies produced by the body in response to infection, or the DNA of the virus|
|Hepatitis C Testing||Blood sample||Detects antigens, antibodies produced by the body in response to infection, or viral DNA|
|Herpes Testing||Blood sample or swab from site of potential infection||Detects presence of virus or antibodies produced by the body in response to infection|
|HIV Tests||Blood sample or oral fluid sample||Detects antigens and/or antibodies produced by the body in response to infection|
|Human Papillomavirus (HPV) Test||Cervical swab||Detects the genetic material (DNA or mRNA) of the virus|
|Syphilis Tests||Blood sample or swab from site of potential infection||Detects antibodies produced by the body in response to infection, the bacterium itself, or its DNA|
|Trichomonas Testing||Urine sample or vaginal, cervical, or urethral swab||Detects the parasite or its DNA|
Getting Tested for STDs
STD tests are usually ordered by a doctor. Before prescribing a test, the doctor asks about your risk factors for STDs, including your sexual and health history. The doctor also asks about any signs or symptoms of STD infections in order to determine the most appropriate testing strategy.
While STD testing is often performed in a hospital or doctor’s office, many people get tested for STDs at clinics and other community health programs. Community health programs may offer free and confidential STD testing.
When interpreting STD test results, it’s important to remember that STDs have window periods. A window period is the time between when a person is infected with an STD and when the STD shows up on a test. If an STD test is taken too soon after infection, the results will not be accurate and the test will need to be repeated after the window period ends.
At-home testing is available for several STDs. These at-home tests usually involve collecting a urine sample, using an oral swab, or drawing a drop of blood from a fingerstick. Test samples are then mailed to a laboratory that analyzes your blood, oral fluid, and/or urine for STDs.
Results from at-home STD testing aren’t always definitive. Rather, an STD test result needs to be interpreted by a doctor who can also consider your symptoms and health history.
At-home STD testing can show a negative result in someone who does have an infection, also called a false negative result. It can also indicate a positive result when someone doesn’t actually have an infection, or a false positive result. Because of this, your doctor will likely want to do follow-up testing if your at-home test indicates that you may have an STD.
Sources and Resources
These resources offer additional information about STDs and their symptoms, causes, and treatment:
- CDC: Sexually Transmitted Diseases (STDs)
- American Sexual Health Association: STDs A to Z
- ACOG: How to Prevent Sexually Transmitted Infections (STIs)
- MedlinePlus: Sexually Transmitted Diseases
- NICHHD: Sexually Transmitted Diseases (STDs)
- NIAID: Sexually Transmitted Diseases
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