Medical-Surgical Nursing · Genitourinary and Reproductive Systems
Sexually Transmitted Infections
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In 30 seconds
Sexually transmitted infections (STIs) are infections passed primarily through sexual contact — vaginal, anal, or oral sex — and sometimes from a pregnant person to their fetus or newborn. The term STI An infection passed mainly through sexual contact Full entry → is preferred over "sexually transmitted disease" because many infected people have no symptoms at all and are therefore "infected" without being "diseased" — which is exactly why they can unknowingly pass the infection on.
STIs are caused by every major kind of microbe: bacteria (chlamydia, gonorrhea, Syphilis Bacterial STI that develops in stages Full entry →), viruses (herpes simplex virus or HSV, human papillomavirus or HPV Very common virus; some strains cause warts, others cancer Full entry →, HIV Virus that attacks the immune system Full entry →, hepatitis B), parasites (trichomoniasis), and ectoparasites (pubic lice, scabies). Because they are common, frequently silent, and can cause serious complications — pelvic inflammatory disease, infertility, ectopic pregnancy, cancer, and lifelong viral infection — STIs are a public health priority and a core topic for nurses in every setting.
Why this matters
Nurses are often the first and only clinicians a person talks to about sexual health. A nonjudgmental approach and straightforward questions ("Are you sexually active? Do you use condoms?") open the door to testing, treatment, and prevention. Untreated STIs have real consequences: chlamydia and gonorrhea can scar the fallopian tubes and cause infertility or ectopic pregnancy; HPV causes nearly all cervical cancers; syphilis in pregnancy can harm the fetus. STIs are also reportable diseases in most jurisdictions — public health law requires cases to be reported so contacts can be notified — and the nurse's role in reporting, Partner notification Telling (or helping the patient tell) sexual partners they may be exposed Full entry →, and education is a standard exam and practice topic.
The college version
Core Concepts
How STIs are transmitted — and why "no symptoms" doesn't mean "no risk"
STIs spread by contact with infected body fluids (semen, vaginal fluids, blood) or with infected skin and mucous membranes. This matters for two reasons. First, prevention is about exposure, not symptoms: a person with no symptoms can still transmit. Second, condoms reduce transmission of many STIs but do not eliminate it — HPV and HSV can be passed by skin-to-skin contact in areas a condom does not cover. Testing is the only way to know, and many guidelines recommend routine screening for sexually active people regardless of symptoms. (Screening recommendations vary by organization and jurisdiction.)
Bacterial STIs: treatable, but dangerous if missed
Chlamydia and gonorrhea are the classic "silent" bacterial STIs — most infected people, especially women, have no symptoms or only mild discharge or burning. Untreated, they can ascend into the upper reproductive tract and cause pelvic inflammatory disease (PID Infection of the female upper reproductive tract Full entry →), with lasting damage to the fallopian tubes. Syphilis is the great imitator: it develops in stages — a painless sore (chancre) in the primary stage, a rash in the secondary stage, then a long latent period; without treatment, late (tertiary) syphilis can damage the heart and brain years later. Syphilis in pregnancy can be transmitted to the fetus (congenital syphilis), which is why routine prenatal testing is standard. Bacterial STIs are generally cured with antibiotics, but regimens change with resistance patterns — nurses teach adherence and partner treatment and follow current guidelines rather than memorized regimens.
Viral STIs: controllable, not curable
HSV (herpes) causes recurrent painful blisters or ulcers on the genitals or mouth; the virus stays in the body for life and can shed (and transmit) even between outbreaks. HPV is extremely common; most infections clear on their own, but certain strains cause genital warts and others cause cervical, anal, and other cancers — which is why HPV vaccination and routine cervical screening are public health cornerstones. HIV attacks the immune system; without treatment it progresses to AIDS, but with modern antiretroviral therapy people with HIV can live long, healthy lives and, when the virus is suppressed, do not transmit it sexually. Hepatitis B infects the liver, can become chronic, and is preventable by vaccination. None of these viruses is cured by medication, but all can be managed — the nurse's job includes education about suppression, vaccination, and follow-up.
Parasitic and ectoparasitic STIs
Trichomoniasis, caused by a protozoan, produces vaginal itching, discharge, and odor in many people (though some have no symptoms). Pubic lice ("crabs") and scabies are tiny ectoparasites that infest hair and skin, causing intense itching. These are highly treatable, but partners must be treated too, or the infection bounces back and forth.
Prevention, testing, and the nursing role
Prevention is layered: condoms reduce most bacterial and viral STIs; vaccination prevents HPV and hepatitis B; testing finds silent infections; and partner treatment prevents reinfection. The nursing role includes taking a sexual history without judgment, offering and explaining testing, teaching about warning signs, supporting adherence, discussing how to tell partners, and reporting cases as required by law. Remember confidentiality — and that shame and stigma are the biggest barriers to care; the tone of the conversation is part of the treatment. Scope varies by setting: in some places nurses test, treat, and counsel within protocol; in others, treatment is provider-ordered.
STIs in special populations
Pregnancy adds urgency: untreated syphilis, gonorrhea, chlamydia, HIV, and hepatitis B can affect the fetus or newborn, and routine prenatal screening is standard. Adolescents have high STI rates and may need extra support with confidentiality and access. People with HIV or immunosuppression may have more severe presentations. In every case, person-first language and a nonjudgmental approach are non-negotiable — the goal is care, not blame.
Common Confusions
| Do Not Confuse | With | Difference |
|---|---|---|
| STI | STD | STI includes people with no symptoms; STD implies illness. Most infected people are asymptomatic, so STI is the more accurate umbrella term |
| Chlamydia | Gonorrhea | Both common bacterial STIs with similar risks, but they are different organisms with different treatments; co-infection is common, so both are usually tested together |
| HSV-1 | HSV-2 | HSV-1 is typically oral ("cold sores") but can cause genital infection; HSV-2 is typically genital. Both can infect either site |
| HPV warts | HPV cancer strains | Wart-causing strains differ from the high-risk strains linked to cervical cancer; someone can have warts and never get cancer, and vice versa |
| HIV infection | AIDS | HIV is the virus; AIDS is the advanced stage of untreated disease. With treatment, people with HIV do not progress to AIDS |
| "I feel fine" | "I don't have an STI" | Most STIs are asymptomatic; feeling fine is not a negative test result |
| Condoms prevent all STIs | Condoms prevent most STIs | Condoms greatly reduce risk but do not cover all skin, so HPV and HSV can still be transmitted |
Eli explains
The same idea, in plain words
Explain it like I’m 10
Germs can be passed from one person to another when people have sex, and these germs are called STIs. Some are caused by bacteria and can be cured with medicine, but others are caused by viruses and stay in the body forever, even though medicine can keep them under control. The sneaky part is that a person can have an STI and feel totally fine, so they can pass it to someone else without knowing. That's why doctors and nurses encourage testing, condoms, and vaccines, and why they talk about sexual health without making people feel bad.
Worked example
Nineteen-year-old Sam comes to the clinic "just for a checkup" and mentions, almost as an aside, that a former partner told them to "get tested." Sam has no symptoms. Your sexual history is matter-of-fact — partners, condom use, past testing — without a hint of judgment, and you explain that many STIs cause no symptoms, so a test is the only way to know. Sam agrees to testing for chlamydia, gonorrhea, syphilis, and HIV.
The test comes back positive for chlamydia. Your role now: (1) explain the result clearly, normalize it ("This is very common and completely treatable"), and review the treatment plan and the importance of finishing it; (2) emphasize that the former partner and any current partner should be tested and treated, and offer guidance on how to have that conversation; (3) reinforce that chlamydia usually causes no symptoms, which is why the follow-up test matters; (4) document and report per your jurisdiction's communicable disease requirements; and (5) use the visit as a prevention moment — condoms, vaccines (HPV, hepatitis B), and routine screening. Notice what you did not do: you did not lecture, blame, or assume anything about Sam's partners. That nonjudgmental stance is what keeps patients coming back.
Key takeaways
- STI (infection) vs STD (disease): many STIs cause no symptoms — that is why "infection" is preferred and why screening matters.
- Chlamydia and gonorrhea are often silent; untreated, they cause PID, infertility, and ectopic pregnancy.
- Syphilis is staged (primary chancre → secondary rash → latent → tertiary) and can be passed to a fetus — prenatal screening is standard.
- Bacterial STIs are curable with antibiotics; viral STIs (HSV, HPV, HIV, hepatitis B) are manageable but not curable.
- HPV is linked to cervical and other cancers — vaccination and routine cervical screening are key prevention tools.
- Condoms reduce — but do not eliminate — STI risk, because HSV and HPV spread by skin contact outside the covered area.
- Partners must be treated too, or reinfection is likely; many STIs are reportable, and reporting/partner notification are legal and ethical duties.
- Nonjudgmental history-taking, confidentiality, and person-first language — stigma keeps people from testing and treatment.
Check yourself
6 review questions from the chapter. Try each one, then open the answer.
Why is "STI" preferred over "STD"?
Show answer
Because many infected people have no symptoms, they are infected (STI) but not diseased (STD); the term STI encourages testing and reduces stigma.
What are the major complications of untreated chlamydia and gonorrhea in women?
Show answer
Ascending infection causes pelvic inflammatory disease (PID), which can scar the fallopian tubes, leading to chronic pelvic pain, infertility, and increased risk of ectopic pregnancy.
Name the four stages of syphilis and one key feature of each.
Show answer
Primary: painless chancre (sore). Secondary: rash (often on palms/soles) and systemic symptoms. Latent: no symptoms for years. Tertiary (late): damage to heart, brain, nerves, and other organs.
Which STIs are curable, and which are manageable but not curable?
Show answer
Curable: bacterial (chlamydia, gonorrhea, syphilis) and parasitic (trichomoniasis) infections. Manageable but not curable: viral infections — HSV, HPV, HIV, hepatitis B.
Why can a condom fail to prevent HPV or HSV transmission?
Show answer
Because HSV and HPV are transmitted by skin-to-skin contact in areas a condom does not cover; condoms reduce but do not eliminate the risk.
List three components of the nurse's role in STI care.
Show answer
Nonjudgmental sexual history-taking; offering and explaining testing; education on prevention (condoms, vaccines), treatment adherence, and partner notification; reporting reportable diseases; and supporting patients with confidentiality and person-first care. (Any three is a good answer — and note scope varies by state and institution.)
Study tools & related lessonsKey vocabulary · Related
Key vocabulary
- STI
- An infection passed mainly through sexual contact
- Asymptomatic
- Having an infection but no symptoms
- Syphilis
- Bacterial STI that develops in stages
- HSV (herpes)
- Lifelong viral infection causing recurrent sores
- HPV
- Very common virus; some strains cause warts, others cancer
- HIV
- Virus that attacks the immune system
- PID
- Infection of the female upper reproductive tract
- Reportable disease
- An infection that must be reported to public health authorities
- Partner notification
- Telling (or helping the patient tell) sexual partners they may be exposed
Sources & references
This lesson was adapted from the open educational references above; their licenses and attributions are preserved. See Copyright & Licensing.
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