Sexually Transmitted Infections: What You Need to Know

| Posted On Sep 03, 2015 | By:

Sexually transmitted infections (STIs), also called sexually transmitted diseases (STDs), are some of the most widespread infections, with almost 20 million STIs reported in America last year. Anyone who is sexually active can get an STI.

STIs are typically spread from one person to another through vaginal, anal, or oral sex, but they can also be passed by sharing needles, during the delivery of a baby, or during breastfeeding.

Some people have symptoms, but many do not. Because it’s hard to know who might have an STI, it’s important to take steps to protect yourself and others.

Here is a list of some of the most common STIs and their symptoms:

Herpes causes painful blisters, usually on the genitals or mouth, that go away after a week or two. It also increases the chance that a pregnant woman will need a cesarean section to avoid spreading herpes to her newborn. Right now, herpes symptoms can be treated and prevented but not cured with medicine.

Human Papilloma Virus (HPV) causes almost all cases of cervical cancer in women, penile cancer in men, and (among others) anal and oral cancers in both men and women. It is highly contagious, and there are over 100 strains of the virus. A few strains can cause cancer, others can cause warts, and many have no known harmful effects. Although cancers and warts can be treated, the virus cannot be eliminated.

Syphilis often starts with a small, painless sore on or near the genitals or anus. Even after the sore heals, the infection continues to spread, and if left untreated, syphilis can seriously damage the heart and brain.

Human Immunodeficiency Virus (HIV) – When left untreated, HIV leads to Acquired Immunodeficiency Syndrome (AIDS), which weakens the immune system. Infected and untreated people are at high risk of developing life-threatening infections and cancers. So far, there is no cure for HIV, but medicine can prevent the infection (this is called pre-exposure prophylaxis, PrEP) and reduce these complications in almost everyone infected with the virus. If someone is HIV positive but does not have a detectable level of virus in their body because they are taking medication, they are not infectious to others.

Hepatitis A may cause flu-like symptoms of extreme fatigue, muscle aches and pains, low-grade fever, and nausea and vomiting. It is sometimes passed on through sexual activity (usually in men who have sex with men), but most cases are not spread through sex but from contaminated food. It injures the liver, and some people become very ill, but it rarely is fatal, and people usually make a full recovery.

Hepatitis B – Most people who have an acute hepatitis B infection don’t have symptoms, but if you do have symptoms, they can include fatigue, mild fever, dark urine, and jaundice.  It attacks the liver and is commonly sexually transmitted. Hepatitis B can cause cirrhosis (scarring that keeps the liver from properly cleaning toxins from the blood) and liver cancer.

Hepatitis C – Most people who are infected with hepatitis C don’t have symptoms. The virus can be spread through the blood or body fluids of someone who is infected. It damages the liver causing cirrhosis and liver cancer, particularly in people who also drink alcohol. There are medications available that can cure many cases of hepatitis C.

Chlamydia and gonorrhea – Some individuals have no symptoms of these STIs, but others may experience painful urination or a vaginal, anal, or penile discharge. These infections can cause premature birth and pelvic inflammatory disease (PID) in women. PID can scar and block reproductive organs leading to infertility and ectopic pregnancy.

Trichomoniasis (“trich”) often causes a bad-smelling vaginal odor and often pain with intercourse. It can trigger premature birth in pregnant women but is usually asymptomatic in men.

Pubic lice (“crabs”) are small insects that lay eggs in pubic hair and cause intense itching. If over-the-counter lotions or shampoos do not cure your pubic lice, talk to your clinician about prescription medication.

What should I do if I think I have an STI?

Call your clinician right away. Don’t let any embarrassment keep you from talking honestly with a clinician about your sex life. Ignoring symptoms or worries can make the problem—if you have one—more serious for you and your partner. Do not have sex with anyone until you find out if you have an STI and get treated, if necessary.

How can I protect myself against STIs?

The only foolproof way to avoid an STI is not to have sex. If you do have sex, keep in mind that semen, vaginal fluids, feces, and saliva can carry STIs. Skin-to-skin contact between the mouth, vagina, penis, or anus spreads these diseases.

Should I be tested for STIs?

Talk with your clinician about this. Depending on your situation, your clinician may suggest tests every six to 12 months and/or tests anytime you have symptoms that might be caused by an STI. If you have a new partner, both of you may want to be tested. It’s best to do this before you start having sex.

For testing, a sample of your blood or urine is usually sent to a lab. Your clinician may do a physical exam and take a sample of any discharge. Generally, women have a pelvic exam so that a sample can be taken from the cervix as well.

How are STIs treated?

Treatment depends on which STI you have. Several STIs, including chlamydia, gonorrhea, and syphilis, can be cured with antibiotics. Medicine to get rid of pubic lice can be bought without a prescription in drugstores. Certain STIs—such as HIV, herpes, and HPV—can not be completely cured, but a clinician can treat the symptoms with prescription medicine or by other methods.

Do I have to tell my partner if I have an STI?

You should definitely tell your sexual partner(s) if you have an STI. Even if your partner has no symptoms, they need to be tested and possibly treated, too. This is important to your partner’s health. It will also keep you—and others—from getting infected again. If you are worried about telling your partner(s), talk with your clinician, and they may be able to help.

What if my partner tells me they have an STI?

Call your clinician to discuss what test(s) might be appropriate. More than one test may be recommended because certain STIs are often found together.

For more information, see the Centers for Disease Control and Prevention’s Fact Sheets.

Content updated August 2021

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About Dr. Bryan Bordeaux

Dr. Bryan Bordeaux joined Atrius Health in 2007 as an internist at our Copley practice. He is board-certified in internal medicine. He received his medical degree from Philadelphia College of Osteopathic Medicine, Philadelphia, PA and completed his internship and residency at United Health Services Hospitals, Johnson City, NY and a general internal medicine fellowship at Johns Hopkins in Baltimore. He is an active faculty member at Harvard Medical School and has a clinical interest in men’s health issue. Dr. Bordeaux enjoys baseball, cooking, photography, reading, and travel.



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