STD Transmission Risk: If Your Partner Has an STI

Yes. Sexually transmitted infections (STIs) are transmitted through sexual contact with an infected partner. Transmission can occur even when the partner is asymptomatic.

Transmission Routes

• Vaginal, anal, oral sex (penetrative and non‑penetrative genital contact)
• Shared sex toys without barriers/cleaning
• Vertical (mother‑to‑child) during pregnancy, delivery, breastfeeding

Common STIs & Asymptomatic Carriage

STI	Asymptomatic Rate
Chlamydia	70–80% women, 50% men
Gonorrhea	10–50%
Trichomoniasis	~70% men, variable women
HSV‑2	80% unaware of infection
HPV	Most infections subclinical
HIV	Acute retroviral syndrome only 50–90%; then clinical latency years

Prevention

1. Condoms (external/internal) every act – reduce but not eliminate risk.
2. Vaccination: HPV (9‑valent), Hepatitis B.
3. PrEP for HIV (daily TDF/FTC or event‑driven).
4. Regular screening: per CDC guidelines (age, risk, anatomy).
5. Mutual monogamy with verified negative status.
6. Communication: discuss testing history before sex.

If Exposure Suspected

• Seek testing ASAP (window periods vary).
• PEP for HIV within 72 h (ideally <24 h).
• Empiric treatment for chlamydia/gonorrhea if high risk and follow‑up uncertain.