Latex Condoms and their Effectiveness against Various STD's

TALK SEX repeatedly stresses the importance of using condoms for safer sex, but condoms are not effective against all STD's. The Centers for Disease Control – CDC – has published an excellent fact sheet on the effectiveness of condoms against various sexually transmitted diseases. This is an overview of that information:


HIV is the deadliest STD because it leads to AIDS, which is usually fatal. Condoms are highly effective in preventing the transmission of HIV.

“Laboratory studies have shown that latex condoms provide an essentially impermeable barrier to particles the size of STD pathogens.”

In order for condoms to be effective, they must be used every time you have vaginal or anal sex.


Discharge Diseases – Gonorrhea, Chlamydia, Trichomoniasis

These diseases are classified as 'discharge diseases' because they are spread through genital secretions, such as male ejaculate and vaginal fluids. HIV is also a discharge disease.

Latex condoms, when used consistently, can help to reduce transmission rates. Again, the STD pathogens cannot penetrate the latex barrier.

Since only areas covered by the condom are protected, discharge diseases can spread to unprotected areas. For example, oral sex with no condom can result in gonorrhea of the throat.

“Many of the available studies were not designed or conducted in ways that allow for accurate measurement of condom effectiveness against the discharge diseases. More research is needed to assess the degree of protection latex condoms provide for discharge diseases, other than HIV.”


Genital Ulcer Diseases (Herpes, syphilis, chancroid) and Human Papilloma Virus (HPV)

These are 'skin-to-skin' diseases.

“Latex condoms can reduce the risk….only when the infected area or site of potential exposure is protected.”

“Genital ulcer diseases….are transmitted primarily through 'skin-to-skin' contact from sores/ulcers or infected skin that looks normal. HPV infections are transmitted through contact with infected genital skin or mucosal surfaces or fluids. Genital ulcer diseases and HPV infection can occur in male or female genital areas that are, or are not, covered (protected by the condom).”

In other words, if you have a wart or a herpes sore on your penis, and you wear a condom over it, the disease will not be transmitted through the condom. However, most genital sores appear on other genital areas that are NOT covered by a condom. The disease can be spread by simply rubbing up against the sore or the infected area. Herpes is particularly sneaky, because the person with the disease may not have an active sore, but may still be 'shedding' skin cells that contain the virus from the infected area .

Oddly, as the CDC paper points out, even though condoms have minimal effectiveness in regards the transmission of HPV (since it is spread 'skin-to-skin'), studies have shown that condom usage reduces the risk of diseases related to HPV, including genital warts and cervical cancer.

“HPV infection is believed to be required, but not by itself sufficient, for cervical cancer to occur. Co-infections with other STD's may be a factor….More research is needed…”

Simplified Chart of Condom Effectiveness with Consistent Use

HIV Highly effective protection
Gonorrhea Medium to high effectiveness
Chlamydia Medium to high effectiveness
Trichomoniasis Medium to high effectiveness
Herpes Low effectiveness
Syphilis Low effectiveness
Chancroid Low effectiveness
HPV – Human Papillomavirus (warts) Low effectiveness, but does reduce risk of cervical cancer associated with HPV

All quotes are courtesy of the CDC web site. To read the entire fact sheet on LATEX CONDOMS, you can visit the CDC web site at