Michael P. Hirsh, M.D.
What are sexually transmitted infections?
Sexually transmitted infections (STIs) are a family of diseases that people acquire through sexual contact with people who are already infected. Some examples of STIs are: chlamydia, gonorrhea, hepatitis B, HIV, syphilis and the human papillomavirus (HPV). STIs cause a variety of illnesses, including genital skin lesions, painful urination and systemic diseases such as AIDS.
How do I avoid STIs?
The method of transmission can change depending on the STI, but they are generally passed through unprotected sexual activity. Abstaining from any type of sexual activity is the most reliable way to avoid infection with an STI.
For those who are sexually active, there are many ways to reduce the risk of STI transmission. Male latex condoms are highly effective at reducing STI transmission, in addition to preventing unintentional pregnancy. In order to be fully effective, male condoms must be worn correctly and used for all types of sexual intercourse - anal, vaginal and oral.
There are also vaccines for two different STIs: hepatitis B and HPV. Ideally, these vaccines should be given before any boy or girl becomes sexually active. Hepatitis B and HPV are both capable of causing cancer, so vaccination against these STIs is especially important.
What should I do if I think I have an STI?
Contact your doctor immediately. In most cases, your doctor will be able to order a quick test to allow him or her to diagnose and treat your STI. By treating the STI early on you may prevent future complications. Also, the best way for you to avoid transmitting an STI to somebody else is to know whether or not you are infected.
What is HIV/AIDS?
The Human Immunodeficiency Virus (HIV) is a virus that infects and kills human immune system cells. When a large portion of immune system cells have been killed, people infected with HIV can develop Acquired Immunodeficiency Syndrome (AIDS). Once infected with HIV, a person will have it for life. However, medications can help keep immune system cells alive and prevent the development of AIDS.
There are currently about 1.1 million people living with HIV in the United States, and most cases occur in urban areas.
How do people get infected?
HIV is passed through contact with bodily fluids, most often through sexual contact or through sharing of intravenous needles. HIV is transmitted during sexual contact when blood, semen, rectal, or vaginal fluids from an HIV-positive person come in contact with mucus membranes of an HIV-negative person. When needles are shared, HIV-infected blood can be transmitted directly into the bloodstream of an HIV-negative person.
How can I protect myself?
For people who are sexually active, there are three main ways to protect against HIV infection: using condoms consistently and correctly, choosing safer sexual practices and reducing the number of sexual partners.
Male condoms are highly effective at preventing HIV infection and they also prevent other sexually transmitted diseases like gonorrhea and chlamydia. Although condoms are highly effective, there is still a risk of HIV transmission using condoms. Practicing oral sex rather than anal or vaginal sex reduces the risk of HIV transmission.
Reducing the number of sexual partners can reduce the risk of HIV transmission because it's less likely that you will encounter someone with an HIV infection. In addition, up to 16% of HIV-infected individuals are not aware that they are infected.
What should I do if I'm exposed?
Contact your doctor immediately. If you think you have been exposed to HIV, your doctor will be able to offer you a post-exposure prophylaxis that may prevent the virus from making enough copies to infect you. With urgent questions you can also call the free Massachusetts HIV/AIDS hotline at 800-235-2331.