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Facts About Sexually Transmitted Infections
What You Need to Know to Protect You and Your Family
Protecting yourself against sexually transmitted infections (STIs) includes more than just using condom. Find out what steps you can take to protect you and your partner(s).
STIs are caused by bacteria, viruses, or other organisms. Treatments depend on the cause of the infection. Bacterial infections can be treated and cured with antibiotics. However, some bacteria are becoming resistant to antibiotics making treatment lengthier or more difficult. Viral infections are generally not curable, but medications can be used to ease symptoms and increase the time between symptoms flare-ups. Drug resistance can also be seen with some viruses. Other organisms include parasites, fungi, or protozoa. These are treated with antibiotics or other types of medications (depending on the organism).
STIs are usually spread through sexual contact, including vaginal, oral, and anal sex. The viruses and bacteria that cause STIs are normally carried in the semen, vaginal fluids, or blood. They enter the body through tiny tears or cuts in the mouth, anus, or genitals. STIs can be passed from person-to-person even without having sexual intercourse. For instance, someone can contract herpes or genital warts through skin-to-skin contact with an infected sore or area.
With most STIs, symptoms do not appear right away. Latency periods vary among specific infections. This makes it easier to transmit an infection to others.
Abstaining from sex or intimate contact is the most effective way to prevent an STI. If you are sexually active, you can reduce your chances of an STI by avoiding high-risk behaviors like unprotected sex and sex with multiple partners.
A latex condom should always be used when having sex. It's important to use a condom consistently and correctly. Vaccines are available for some infections. If you have questions about condom use or vaccination schedules, talk to your doctor.
When to See a Doctor Right Away
You should see a doctor right away if you have:
- Abnormal or strong-smelling discharges, pus, or odors from the vagina, penis, or rectum
- Boils, blisters, polyps, growths, sores, or warts in these areas
- Burning sensations in these areas
- Bleeding in these areas
- Irritation, tenderness, swelling, rashes, itching in these areas
- Painful intercourse
- Vaginal yeast infections
- Pain or burning sensation during urinating
- Pain or burning sensation during bowel movements
- Lower abdominal or pelvic pain
- Sexual contact with someone who has a known STI
Other Possible Symptoms of an STI
Other symptoms of a STI may include:
- Weight loss that is constant, rapid, or unexplained
- Coatings of the mouth, throat, or vagina
- Muscular pain, aching joints, general weakness, feeling tired
- Coughs, chills, night sweats, or fevers
- Bowel problems, diarrhea, vomiting, appetite loss, nausea
- Vaginal pain
- Headaches, lightheadedness, vision loss, hearing loss, psychiatric symptoms
- Discolored skin, hair loss, jaundice (yellowing of the skin or whites of the eyes)
- Swollen glands, sore throat, fatigue
Bacterial vaginosis (BV) is caused by a change in the balance of different kinds of bacteria in the vagina. When there are symptoms, they often appear as a form of vaginitis—an irritation of the vagina often associated with a vaginal discharge. BV is not sexually transmitted, though sexual activity increases the risk because it can change the balance of bacteria.
- Treatment—Antimicrobial creams are applied to the vagina or antibiotic pills taken by mouth.
- Protection includes:
- Avoid sharing sex toys
- Clean any shared sex toys
- Use condoms during sex and when sharing sex toys
When diagnosed, chlamydia can be easily treated and cured. Untreated, chlamydia can cause reproductive and other health problems. It can cause bladder infections and pelvic inflammatory disease (PID), ectopic pregnancy, and sterility in both men and women. It can also cause eye infections in newborns. It is the most frequently reported infectious disease in the US.
- Treatment—Both partners can be treated successfully with antibiotics.
- Protection—Use condoms during sex.
Cytomegalovirus (CMV) is a member of the herpes virus group. Once infected, a person can carry the virus for life, even though they may never have active symptoms. In babies, transmission of CMV during pregnancy can cause permanent disability, including hearing loss and intellectual disability. This virus is also dangerous for people with weakened immune systems. In healthy adults who are infected with CMV, the symptoms may include swollen glands, sore throat, fever, and fatigue.
- Treatment—There is no cure, but symptoms may be helped with some medications.
- Protection—Condoms can provide protection against CMV during vaginal, anal, and oral intercourse. But, kissing and other intimate touching can spread the virus. Proper hand washing techniques may help reduce transmission, especially to children.
Gonorrhea is caused by specific bacteria, which is transmitted during vaginal, oral, or anal sexual intercourse. It can cause sterility, arthritis, and rarely, heart problems in both men and women. It can also cause eye infections in newborns.
- Treatment—Both partners can be treated successfully with antibiotics. People with gonorrhea often have other STIs, like chlamydia. Infections are treated at the same time.
- Protection—Condoms offer very good protection against gonorrhea.
Hepatitis B Virus
Hepatitis B virus (HBV) can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death.
- Treatment—There is no cure, but in most cases the infection clears within a few weeks. If a chronic infection develops, treatments are available for suppressing the virus. However, some people remain contagious for the rest of their lives.
- Protection—Condoms offer some protection against HBV during vaginal, anal, and oral intercourse. The virus can occasionally be passed through kissing and other intimate touching. Hepatitis B vaccine can prevent this disease.
Herpes Simplex Virus
Both herpes simplex virus-1 (HSV-1) and herpes simplex virus-2 (HSV-2, most common) can be sexually transmitted. HSV-1 is most often associated with cold sores and fever blisters. Like many other viruses, the HSV remains in the body for life. HSV can cause miscarriage or preterm delivery. If active herpes infections are present during childbirth, newborn infants may suffer health problems.
- Treatment—There is no cure but symptoms and outbreaks can be treated or reduced with antiviral medications.
- Protection—Use condoms to help prevent the spread of genital herpes. Keep in mind any exposed skin or sore can infect a partner even while wearing a condom. During symptom outbreaks, you may need to avoid sexual contact.
Human Immunodeficiency Virus
HIV is an infection that weakens the body’s ability to fight off infections. It can eventually lead to AIDS. This compromised immune system can make a carrier more susceptible to pneumonia, cancer, and a variety of opportunistic infections. Like many other viruses, HIV remains in the body for life.
- Treatment—There is no cure. But, HIV and many AIDS-related conditions can be managed to some extent with a variety of treatments. The progression from HIV to AIDS can be delayed with treatment. However, if left untreated AIDS is fatal.
- Protection—Condoms offer very good protection against HIV.
Human papillomavirus (HPV) is a family of more than 100 common viruses. HPV can cause genital warts. The virus is easily spread during oral, genital, or anal sex with an infected partner. Some of these viruses are associated with cervical cancer.
- Treatment—There is no cure for HPV. But, genital warts can be treated or removed in a number of ways including: medication and procedures like cryosurgery—freezing the wart with liquid nitrogen.
- Protection—Condoms may offer some protection against genital HPVs. But, the viruses may shed beyond the area protected by a condom. There is also an HPV vaccine for both males and females that may prevent the most common types.
Molluscum contagiosum can be transmitted by nonsexual, intimate contact. Small, pinkish-white, waxy, round polyps grow in the genital area or on the thighs, and there is often a tiny depression in the middle of the growth. Molluscum contagiosum belongs to a family of viruses called poxviruses, and it is generally spread by skin-to-skin contact. It can be spread sexually if growths are present in the genital area.
- Treatment—Growths may be removed with chemicals, electrical current, or freezing. If not treated, molluscum contagiosum will resolve on its own
- Protection—Condoms may offer some protection against molluscum contagiosum, but the virus may shed beyond the area protected by the condom.
Pelvic Inflammatory Disease
Pelvic inflammatory disease (PID) is a progressive infection that harms a woman's reproductive system. It is usually caused by a chlamydial or gonorrheal infection. It can lead to sterility, ectopic pregnancy, and chronic pain. PID is often caused by STIs, like gonorrhea and chlamydia.
- Treatment—Antibiotics are given.
- Protection—Condoms offer very good protection against infections commonly associated with PID.
Pubic lice are tiny parasitic insects that are generally found in the genital area of humans. Pubic lice are usually spread through intimate or sexual contact. Rarely, infestation can be spread through contact with an infested person's bed linens, towels, or clothes.
- Treatment—Over-the-counter medication is available to treat anyone who may have been exposed to pubic lice. All bedding, towels, and clothing that may have been exposed should be thoroughly washed or dry cleaned, and the home should be vacuumed.
- Protection—Limiting the number of intimate and sexual contacts can help. Also, avoid physical contact with others that may be exposed. Do not share clothing, towels, or bedding with anyone who may have pubic lice.
Scabies is an infestation of the skin with a microscopic mite. It is often sexually transmitted. However, school children often pass it to one another through casual contact.
- Treatment—Over-the-counter medication is available to treat anyone who may have been exposed to scabies. All bedding, towels, and clothing that may have been exposed should be thoroughly washed or dry cleaned, and the home should be vacuumed.
- Protection—Limiting the number of intimate and sexual contacts can help. Also, avoid close physical contact or sharing clothing, towels, or bedding with anyone who has either scabies or an undiagnosed itchy rash—especially a rash that has been present for over a week.
Syphilis is caused by a specific bacteria. It is passed from person-to- person through direct contact with syphilis sores, which occur mainly on the external genitals, vagina, anus, or in the rectum. Sores also can occur on the lips and in the mouth. Though sores disappear without treatment, the bacteria is still in the body causing damage. If left untreated, the syphilis can remain in the body for life and lead to disfigurement, neurologic disorder, and death.
- Treatment—Antibiotics are successful for both partners. But damage caused by the disease in the later phases cannot be undone.
- Protection—Condoms offer good protection during vaginal, anal, and oral intercourse.
Trichomoniasis is a condition caused by a protozoan—a microscopic, one-cell organism. It is a common cause of vaginal infections. It is spread through vaginal intercourse.
- Treatment—Antibiotics are successful for both men and women.
- Protection—Condoms offer good protection.
American Sexual Health Association
Centers for Disease Control and Prevention
SEICCAN—Sex Information & Education Council of Canada
Sex & U—The Society of Obstetricians and Gynaecologists of Canada
2015 Sexually transmitted diseases treatment guidelines. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/std/tg2015/default.htm. Updated January 25, 2017. Accessed October 10, 2017.
Acute HIV infection. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T902526/Acute-HIV-infection. Updated November 4, 2015. Accessed October 10, 2017.
Bacterial vaginosis (BV). EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115494/Bacterial-vaginosis-BV. Updated September 26, 2017. Accessed October 10, 2017.
Congenital cytomegalovirus (CMV) infection and CMV in pregnancy. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116860/Congenital-cytomegalovirus-CMV-infection-and-CMV-in-pregnancy. Updated November 6, 2016. Accessed October 10, 2017.
Cytomegalovirus (CMV) infection in immunocompetent patients. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T906245/Cytomegalovirus-CMV-infection-in-immunocompetent-patients. Updated November 1, 2016. Accessed October 10, 2017.
Genital herpes. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T114875/Genital-herpes. Updated April 27, 2017. Accessed October 10, 2017.
Genital herpes and your baby. Pregnancy Info.net website. Available at: https://www.pregnancy-info.net/stds%5Fherpes%5Fpregnancy.html. Accessed October 10, 2017.
Having sex during your period: Q&A. Epigee website. Available at: https://www.epigee.org/menstruation/sex.html. Accessed October 10, 2017.
Molluscum contagiosum. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116448/Molluscum-contagiosum. Updated August 20, 2015. Accessed October 10, 2017.
Other STDs. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/std/general/other.htm. Updated September 27, 2017. Accessed October 10, 2017.
- Reviewer: EBSCO Medical Review Board Michael Woods, MD
- Review Date: 10/2017
- Update Date: 10/10/2017