Sexually Transmitted Infections Chapter 16 This multimedia product and its contents are protected under copyright law. The following are prohibited by law: any public performance or display, including transmission of any image over a network; preparation of any derivative work, including the extraction, in whole or in part, of any images; any rental, lease, or lending of the program. Copyright 2008 Allyn & Bacon
Sexually Transmitted Infections An Epidemic Bacterial Infections Vaginal Infections Viral Infections Ectoparasitic Infestations Prevention of STIs: More Than Safer Sex Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon An Epidemic An Epidemic Sexually transmitted infections (STIs) Infections communicated through sexual contact There are about 40,000 new cases of HIV/AIDS each year Human papilloma virus (HPV) is present in approximately 20% of American girls over 12, and in more than 50% of some female college populations Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Bacteria A class of one-celled microorganisms that have no chlorophyll and can give rise to many illnesses Gonorrhea “the clap” or “the drip” Characterized by discharge and burning urination If untreated, can lead to pelvic inflammatory disease (PID) and subsequent infertility Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Transmission of gonorrhea Bacteria thrive in warm, moist environments Almost always transmitted by unprotected vaginal, oral, or anal sexual activity or from mother to newborn during delivery It is highly contagious (50% of women and 25% of men infected after one exposure) Pharyngeal gonorrhea Gonorrheal infection of the cavity leading from the mouth and nasal passages to the larynx and esophagus Symptoms include a sore throat Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Ophthalmia neonatorum Gonorrheal infection of the eyes of newborn children who contract the disease by passing through an infected birth canal Symptoms of gonorrhea For men Penile discharge that becomes yellow-green and puslike Urethra becomes inflamed and urination is accompanied by a burning sensation If not treated early, epididymitis, inflammation of the epididymus, can result, which can cause fertility problems Most men experience symptoms within 2 to 5 days after exposure. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Symptoms of gonorrhea For women Primary site of infection for women is the cervix, leading to cervicitis, inflammation of the cervix, which may result in a discharge However, about 80% of women experience no symptoms, are asymptomatic, during the early stages of the infection If left untreated, pelvic inflammatory disease (PID), inflammation of the pelvic region, can result, which may lead to infertility Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Diagnosis and treatment of gonorrhea Involves clinical inspection of the genitals by a physician and the culturing and examination of a sample of genital discharge Antibiotics are the standard treatment. Sex partners also should be examined. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Syphilis May progress through several stages of development Starting from chancre (a sore or ulcer) to a skin rash to damage to cardiovascular or central nervous systems In the latent stage, it may lie “dormant” for 1 to 40 years. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Transmission of syphilis Most often transmitted by vaginal or anal intercourse or oral-genital or oral-anal contact Can be transmitted by contact with a chancre congenital syphilis: transmission to fetus, which can impair vision & hearing or deform bones & teeth Symptoms and course of syphilis Primary, secondary, latent, and tertiary stages Symptoms of primary and secondary stages eventually disappear. In the tertiary stage, neurosyphilis (infection of the central nervous system) and general paresis can result. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Diagnosis and treatment of syphilis Primary-stage syphilis is diagnosed by a clinical exam. VDRL Blood test named after the Venereal Disease Research Laboratory of the U.S. Public Health Service that tests for the presence of antibodies, specialized proteins that recognize and attack invading organisms or substances, to the syphilis bacterium Penicillin and other antibodies are the standard treatment. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Chlamydia It is more common than gonorrhea and syphilis in the US Transmission Vaginal or anal intercourse Contact with the eye Oral sex During birth Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Symptoms of chlamydia Usually are similar to gonorrhea, but milder In men, it can lead to nongonococcal urethritis (NGU), inflammation of the urethra. In women, chlamydial infections typically result in infections of the urethra or cervix and PID if untreated. At least 25% of men and 70% of women have no noticeable symptoms. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Diagnosis and treatment of chlamydia Cervical smear for women Swab inserted through penile opening for men Antibiotics other than penicillin are the standard treatment. Sex partners should be tested and treated, if necessary. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Bacterial Infections Other Bacterial Diseases Chancroid (also called soft chancre) Cluster of bumps or pimples on the genitals or anus, which becomes an open sore or ulcer Shigellosis Fever and severe abdominal symptoms Granuloma inguinale Painless red bumps in the groin area; can develop into more serious symptoms if untreated Lymphogranuloma venereum (LVG) Flu-like symptoms, lymph node swelling Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Vaginal Infections Vaginitis Any type of vaginal infection or inflammation Symptoms include a malodorous discharge, genital itching, and burning during urination The great majority involve bacterial vaginosis, candidiasis, or trichomoniasis Bacterial vaginosis: Usually caused by an overgrowth of bacterium; primary symptom is discharge, but sometimes there are no symptoms Candidiasis: Often caused by an overgrowth of a yeastlike fungus; also called yeast infection; symptoms include itching and a thick, curd-like discharge; can be passed between sex partners Trichomoniasis: Caused by a protozoan and is the most common parasitic STI; symptoms include burning, itching, painful urination, and a foamy discharge Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections HIV/AIDS Human immunodeficiency virus (HIV) A virus, which can be sexually transmitted, that destroys white blood cells in the immune system, leaving the body vulnerable to life-threatening diseases Acquired immunodeficiency syndrome (AIDS) Caused by the human immunodeficiency virus (HIV) Characterized by destruction of the immune system so that the body is stripped of its ability to fend off life-threatening diseases Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Prevalence of HIV/AIDS Nearly 1 million Americans live with HIV/AIDS Approximately 40 million people in the world live with HIV/AIDS An estimated 70 million people will die of HIV/AIDS-related diseases over the next two decades, unless antiretroviral drugs are available to everyone. An estimated 4.3 million people were infected in 2006 AIDS caused the death of nearly 3 million people in 2006 Worldwide, HIV affects men and women equally; in the US, it is found more commonly among men who engage in homosexual relations or who share needles for drugs Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections INSERT FIGURE 16.5 HERE (GLOBE THAT PORTRAYSS “ADULTS AND CHILDREN ESTIMATED TO BE LIVING WITH HIV, 2006”) Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections The immune system and HIV/AIDS The immune system produces white blood cells, leukocytes, that kill pathogens. Leukocytes recognize pathogens by their surface fragments, known as antigens, to which antibodies attach themselves. The immune system promotes inflammation, which allows for the expanded flow of leukocytes to the region. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Effects of HIV on the immune system Spikes on the surface of HIV bind to immune system cells, CD4 cells and others, which it uses to make copies of itself. Destroys the CD4 cells in the process HIV eventually leads to a drop in the number of CD4 cells. People are the most vulnerable to opportunistic infections when their CD4 count falls below 200 per cubic millimeter of blood. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Progression of HIV/AIDS Mild flulike symptoms may be experienced shortly after infection Most people are symptom-free for years while others may enter a symptomatic state. AIDS is connected with a wasting syndrome and certain opportunistic diseases: Pneumocystis carinii pneumonia (PCP), Kaposi’s sarcoma, toxoplasmosis of the brain, and Herpes simplex If untreated, AIDS almost always leads to death within a few years. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Transmission of HIV HIV contaminates certain bodily fluids Blood, semen, vaginal secretions, breast milk Exposure to the fluids (excluding breast milk) can occur through: Vaginal, anal, or oral-genital intercourse Sharing hypodermic needles or being stuck by a needle Blood transfusions and organ and tissue transplants Artificial insemination During childbirth Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Factors affecting the risk of sexual transmission of HIV Number of sexual contacts with an infected partner Type of sexual activity The amount of virus in bodily fluid The presence of other sexually transmitted infections Circumcision Genes How HIV is not transmitted Donating blood Casual, everyday contact Insect or animal bites Airborne germs or contact with contaminated food Sharing work or home environments Kissing Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Diagnosis of HIV infection and AIDS Enzyme-linked immunosorbent assay (ELISA) A widely used test for HIV antibodies Performed on blood, saliva, or urine OraQuick A quicker antibody test Seropositive: having a pathogen or its antibodies Seronegative: lacking a pathogen or its antibodies Western blot test or PCR (polymerase chain reaction) test Tests given after antibodies are detected that confirm the presence of HIV Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Treatment of HIV/AIDS No human vaccines are available. Drug therapy Zidovudine (AZT) has been the most widely used Inhibits replication of HIV by targeting reverse transcriptase Effective in cutting transmission from pregnant mothers to their developing babies (only 8% of treated mothers delivered infected babies, as opposed to 25% delivered by untreated mothers) Protease inhibitors also block HIV replication. Target the protease enzyme HAART “highly active antiretroviral therapy” A drug “cocktail” used to treat HIV/AIDS, which includes zidovudine, another nucleoside analogue, and a protease inhibitor Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Prevention of HIV/AIDS Efforts exist to prevent transmission from mother to child, from shared needles, and from receiving donated blood or sperm. Sexual transmission is more difficult to prevent. Most prevention efforts focus on education. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Genital Herpes Incurable viral STI Herpes simplex virus type 1 (HSV-1) Causes oral herpes Cold sores or fever blisters on lips, in mouth, on tongue, or in throat Can be transferred to the genitals by the hands or oral-genital contact Herpes simplex virus type 2 (HSV-2) Causes genital herpes Painful, shallow sores and blisters on the genitals Can be transferred to the mouth through oral-genital contact Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Transmission of herpes Oral, anal, vaginal sexual activity Genital herpes typically is spread by sexual activity. And can be transmitted without an outbreak Direct contact with objects, such as toilet seats Touching infected area and then another body part Ocular herpes: A herpes infection of the eye Prodromal symptoms Warning symptoms that signal the onset or flare-up of a disease Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Symptoms of genital herpes Genital lesions or sores Appear about 6 to 8 days after infection May also include headaches, muscle aches, swollen lymph glands, fever, burning urination, and vaginal discharge After symptoms disappear, virus lies dormant and may become reactivated. Recurrences may be due to infections, stress, fatigue, depression, sun exposure, and hormonal changes. Most people with oral herpes experience recurrences. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Diagnosis and treatment of genital herpes Clinical inspection of sores and fluid sample Vaccine called Simplirix (effective in a majority of women) Antiviral drugs Coping with genital herpes Involves psychological issues surrounding: A lifetime of potential recurrences, infecting sex partners, and risks when bearing children Most people learn to cope They view herpes as a manageable illness or problem. Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Viral Hepatitis Inflammation of the liver Major types are hepatitis A, hepatitis B, hepatitis C, and hepatitis D Hepatitis B, hepatitis C, and hepatitis D can be transmitted sexually or through contact with contaminated blood. Most people have no symptoms When symptoms do appear, they often include jaundice Yellowish discoloration of the skin and the whites of the eyes Can lead to chronic liver disease or liver cancer Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Genital Warts Caused by the human papilloma virus (HPV) Warts appear around the genitals and anus Is the world’s most common STI Occurs most commonly in 20- to 24-year-olds Linked to cancers of the genital organs Can be transmitted through skin-to-skin contact during sexual activity and by touching infected towels or clothing Warts can be removed (e.g., by freezing), but there is no cure. Vaccine now available Vaccinates against those strains responsible for cervical cancer Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Viral Infections Molluscum Contagiosum Caused by a pox virus Painless, raised lesions appear on genitals, buttocks, thighs, or lower abdomen Usually appear within two or three months after infection and pose no serious threat Can disappear on their own within six months or can be removed with various solutions or by freezing them. Copyright 2008 Allyn & Bacon
Ectoparasitic Infestations Ectoparasites Parasites that live on the outside of the host’s body May be transmitted sexually or through contact with infested towels, clothing, etc. Pediculosis Infestation by pubic lice, better known as “crabs,” that causes itching Transmitted by contact with infested persons or objects Scabies Infestation caused by a tiny mite that causes itching Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Prevention of STIs Prevention of STIs: More Than Safer Sex Abstinence or monogamy Know the risks Factors associated with risky sexual behavior Perceived low risk of infection Negative attitudes toward condom use Myth of personal invulnerability Remain sober Inspect yourself and your partner Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Prevention of STIs Use latex condoms Use barrier devices during oral sex Avoid high-risk sexual behaviors Wash genitals before and after sex Have regular medical checkups Discuss getting tested before initiating sexual relations Copyright 2008 Allyn & Bacon
Copyright 2008 Allyn & Bacon Prevention of STIs Engage in noncoital sexual activities Outercourse Forms of sexual expressionsuch as massage, hugging, caressing, mutual masturbation, and rubbing bodies togetherthat do not involve the exchange of body fluids Consult a physician if exposure to an STI is suspected Get to know partner before having sex Avoid other high-risk behaviors Copyright 2008 Allyn & Bacon