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The Facts About STDs/STIs

Stigma surrounds sexually transmitted diseases. Know the facts to protect yourself and others.

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Sexually transmitted diseases (STDs) have been an ongoing public health concern for centuries. Despite their long history and readily available information about prevention and treatment, they continue to spread, especially among teenagers and young adults. Nearly half of all new cases in 2018 occurred in people ages 15 to 24, and the Centers for Disease Control and Prevention (CDC) reported more than 2.5 million new cases of gonorrhea, chlamydia and syphilis alone in 2019. 

STDs are easily transmittable, can sometimes go undetected for years and can in the case of HIV increase your risk of contracting another STD. While most are curable with proper diagnosis and treatment, some are not and can have devastating effects, such as infertility and death, if left untreated. STDs can also cause complications in pregnant women that affect both the mother and the unborn child.

The relationship between STDs and STIs

The terms STDs and sexually transmitted infections (STIs) are often used interchangeably, but they are not exactly the same. An STI refers to an infection that can lead to further complications and diseases. These infections may be caused by bacteria, viruses or parasites. Untreated STIs can develop into an STD, which may cause permanent damage to the body. For example, chlamydia and gonorrhea are each easily treatable but otherwise can lead to diseases such as pelvic inflammatory disease (PID), which may cause reproductive harm. The same is true of untreated syphilis, which can lead to dementia, neurosyphilis or ocular syphilis.

Common STIs and STDs

The most common STDs include chlamydia, gonorrhea, hepatitis, herpes, human immunodeficiency virus (HIV), human papillomavirus (HPV), trichomoniasis and syphilis. Less common STDs include chancroid, lymphogranuloma venereum (LGV), mycoplasma genitalium (MG) and pubic lice.

Causes and transmission

STDs are typically spread through genital fluids during sexual activity (vaginal, anal and oral sex) with a partner who already has an STD. Symptoms of an STD are not always visible, meaning some people don't even know they have one. Others may not be willing to share this information with a partner. Therefore, it is important to use responsible prevention methods and seek testing after sex with each new partner to best protect yourself and others.

Pregnant women can spread some STDs to their children during childbirth, and nursing mothers can spread some infections to their babies through breastfeeding.

Most common STD symptoms

Symptoms can vary widely depending on the STD and sometimes do not appear for years, if at all. This makes the spread of STDs a serious concern for public health officials and physicians because it puts people at risk for serious and lasting complications. Symptoms may be mild and/or mimic other conditions, such as a urinary tract infection (UTI) or yeast infection. This can lead to a missed diagnosis or cause people to not seek out treatment. When symptoms present, they have similar manifestations in both men and women but vary.

Symptoms in women can include:

  • itching
  • painful or burning urination
  • abnormal discharge
  • rectal pain, discharge and bleeding (for infections in the rectum that only occur in women who engage in receptive anal intercourse.)
  • sores or blisters on or around the genitals, mouth, throat or rectum
  • bleeding between periods.

Symptoms in men may include:

  • rectal pain, bleeding and discharge, only occur in men who engage in receptive anal intercourse.
  • painful or swollen testicles
  • penile discharge
  • itching
  • painful or burning urination

Syphilis infections have their own unique set of symptoms depending on the stage of the illness, which can progress with severe complications if left untreated. Initial symptoms include painless sores, followed by body rashes; the third stage of syphilis can damage organs and result in death if left untreated.

Diagnosis and testing

An STD diagnosis can be difficult to accept. Common reactions are anger, guilt and shame. The most difficult part can often be informing your sexual partner(s) of your diagnosis, but this is an important step in preventing further infection. In some states, it is mandatory to inform partners when you have been diagnosed with certain STDs, such as chlamydia, gonorrhea and syphilis. Avoiding sex of any kind once you have been diagnosed with an STD is an important measure in preventing transmission to partners. Your doctor can help you determine when it is safe to resume sexual activity after treatment or management.

If you suspect you have an STD or have been exposed to one, your doctor can help you determine what type of testing you should receive. In some cases, a physician can diagnose an STD with a physical exam, but for others, laboratory testing is necessary. These tests, including urine tests, blood tests and taking tissue samples, are generally easy to undergo.

If a partner informs you that they have been diagnosed with an STD, it is important to speak to your doctor and seek testing right away, as you may have acquired the infection without showing symptoms.


There is no singular treatment for all STDs, and testing and treatment should be done under the care of a physician. For example, gonorrhea is easily treatable with antibiotics. However, the disease has been steadily developing a resistance to antibiotics. Treatments of curable STDs are generally effective, but if they persist or recur, further treatment may be needed. Your partner(s) should also seek testing and treatment.

Treatments include medications and antibiotics, such as penicillin, which is the common treatment of syphilis, and ceftriaxone, which is used for the treatment of gonorrhea.

Some STDs, such as herpes and HIV, are not curable, but symptoms can be managed with the help of medications and protective practices that can help reduce the risk of the infection being spread to others.


The only foolproof prevention plan for STDs is abstinence from sex, which may be unrealistic for most adults. But when you are sexually active, you can use effective measures to keep yourself safe.

Maintaining a monogamous relationship with a single partner who has also tested negative for STDs greatly reduces your risk. If you change partners, increase the number of partners or suspect your partner is not monogamous, speak with your healthcare provider to determine how often you should be tested.

Using a condom is not guaranteed to prevent STDs, but it significantly lowers your chances of infection. It is important to use a new condom every time you have sex and to use it properly.

Most STDs are not preventable with vaccines. However, a vaccine for HPV, which can lead to genital warts and cervical cancer, is highly effective. The HPV vaccine is recommended for children and adults ages 9 to 26 who have not already been vaccinated. Additionally, adults through age 45 also may receive the vaccine but should consult a doctor about the pros and cons. Experts recommend early vaccination, preferably before a young person becomes sexually active, as the virus can go undetected for years after the initial infection.

While most STD prevention methods are not 100 percent effective, any measure of protection is better than none. For high-risk individuals, pre-exposure prophylaxis (PrEP), either Truvada or Descovy, is recommended for the prevention of HIV. Being armed with awareness and education can go far against the infection and spread of STDs.

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