Resource Library

Herpes, genital & anal warts, Crabs

Get the basics about symptoms, treatment and prevention for these common STIs.


Herpes can be caused by two different herpes simplex viruses (HSV type I and type II). You can give or get herpes whenever there is direct skin-to-skin contact and during sex. Most oral herpes cases, with fever blisters and cold sores on the mouth, are caused by HSV type I. Most genital herpes cases, with sores on the vagina, penis, anus, or the skin around those areas, are caused by HSV type II. Since many people have oral sex, type I is increasingly causing genital herpes cases.

Once you are infected with HSV, it will live in your body forever. It may cause symptoms occasionally or may not cause any symptoms at all.


Human papillomavirus (HPV) is a virus that can cause genital and anal warts. It can also lead to cervical and anal cancer. There are over 100 different types of HPV, some of which are more harmful than others.

HPV is usually harmless and goes away by itself, but some types can lead to cancer or cause wart-like bumps on the penis, in and around the vagina, on the cervix (opening to a uterus), or around the rectum.

HPV is transmitted by skin-to-skin contact during anal or vaginal sex. Genital warts aren’t the same as those that commonly happen on hands and feet, so one type of wart can’t be passed from one part of the body (e.g., hand or foot) to another (e.g., genital area).

HPV is the most common STI in the U.S. People who have had condomless sex with more than two partners in their lifetime have probably been exposed to HPV. Even if you have a type of HPV that causes warts, you might not get symptoms for months or years, if ever.

There is a vaccine to prevent HPV infection. The CDC issues recommendations about who should get the HPV vaccine. Visit the CDC website for the current recommendation.

We recommend getting tested for STIs every three months if you’re having sex. It’s easy and free at one of our locations.

Crabs & Scabies

Crabs and scabies can infect both men and women and cause extreme itching. Crabs are very small parasites that latch onto pubic hairs and bite the nearby skin. Scabies are mites that dig under the skin, oftentimes in the genital area, to lay their eggs.

Both of these parasites can be transmitted from person to person during sex. They can also be transmitted from contact with clothes, bedding or towels used by an infected person.

Over-the-counter and prescription creams can be used to get rid of crabs and scabies, but should be used under the supervision of your doctor.

When treating scabies or crabs, you also need to wash your clothing, bedding, and towels in hot water to prevent re-infecting yourself. If you have clothes you can’t wash (like a leather jacket), you can store them in a sealed plastic bag for at least 72 hours to kill the bugs.

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