Transmission of STIs

There must be an exchange of body fluids in order to transmit most STIs such as gonorrhea, chlamydia, syphilis, trichomoniasis, HIV, hepatitis.

Others like genital warts, herpes, scabies, and pubic lice can be transmitted by skin-to-skin contact and still others are not necessarily transmitted through sexual contact.

STIs cannot be caught through casual social contact such as shaking hands or hugging.

Modes

Modes of transmission include:

  • Sexual transmission (genital-anal, genital-genital, oral-genital/anal)
  • Skin-to-skin contact (i.e., kissing, non-penetrative sex, body rubbing)
  • Mixture of infectious body fluids (blood, semen, vaginal secretions)
  • Sharing of needles and other drug paraphernalia and needle stick injuries
  • From a pregnant woman to her unborn fetus, or to infants during vaginal delivery or through breast milk
  • Infestations (scabies and pubic lice) can also be transmitted through shared clothing, bedding, linens etc.

 

All information on this page has been reviewed by Options for Sexual Health's Director of Clinical Services, Danielle Chard RN, BSN.

 

Levels of Risk


Levels of Risk

Very High Risk

Receptive anal sex without a condom

Receptive vaginal sex without a condom

High Risk

Insertive (using penis) anal sex without a condom

Insertive (using penis) vaginal sex without a condom

Medium Risk

Giving oral sex without a condom or dental dam (safer if no ejaculation in the mouth)

Sharing sex toys without cleaning or using a new condom

Sexual stimulation of another’s genitals using hands with cuts or broken skin (safer if no contact with secretions, semen, or menstrual blood)

Low Risk

Insertive (using penis) or receptive anal sex with a condom

Insertive (using penis) or receptive vaginal sex with a condom

Very Low Risk

Sexual stimulation of another’s genitals using hands
Giving a man oral sex without putting the head of the penis in mouth

Giving or receiving oral sex with a condom or dental dam

Receiving oral sex without a barrier

Sharing sex toys with cleaning or use of new condom

Tongue kissing

No Risk

Abstinence
Hugging
Massage
Masturbation
Fantasy
Phone sex
Cyber sex
Not sharing sex toys
Sex with a monogamous, uninfected partner

No Risk

Very Low Risk

Low Risk

Medium Risk

High Risk

Very High Risk

Adapted from: As safe as you wanna be. Seattle-King County Dept. of Public Health.