Sexually Transmitted Infections

Transcription

1 Sexually Transmitted Infections 1-1

2 Preventing STIs Abstain from sexual activity. Limit oneself to monogamous relationship with an uninfected person. Condoms can help. Careful washing and inspecting of genitals. Urinating before and after intercourse helps keep bacteria out of the urethra. 1-2

3 Causes and Cures Some STIs are caused by bacteria, some are caused by viruses, a few by other organisms. Bacterial infections can be cured using antibiotics (e.g., chlamydia, gonorrhea, syphilis). Viral infections cannot be cured but they can be treated to reduce symptoms (e.g., herpes, AIDS, genital warts, hepatitis B). 1-3

4 Chlamydia Chlamydia trachomatis is a bacterium that is spread by sexual contact and infects the genital organs of males and females. Approximately 800,000 new cases are reported each year. Adolescent girls have a particularly high rate of infection. 1-4

5 Symptoms of Chlamydia Men: thin, usually clear discharge and mild discomfort on urination, appearing 7 to 14 days after infection. 50% of cases are asymptomatic. Women: 75% of cases are asymptomatic. Diagnosis: Men - urine sample Women - cell sample from cervix or urine sample 1-5

6 Treatment of Chlamydia Curable with azithromycin or doxycycline; does not respond to penicillin. Poorly treated or undiagnosed cases may lead to: urethral damage epididymitis (infection of the epididymis) Reiter s syndrome proctitis in men who had anal intercourse Pelvic Inflammatory Disease (PID) Problems with pregnancy and risks for newborn infants of infected mothers 1-6

7 Risks from Pelvic Inflammatory Disease (PID) Possible infertility, due to scarring of the fallopian tubes Ectopic (tubal) pregnancy Chronic pelvic pain 1-7

8 Prevention of Chlamydia Many infected people are asymptomatic and spread the disease unknowingly. Screening programs can are identify, treat, and cure asymptomatic carriers. The best method of prevention is the consistent use of a condom. 1-8

9 HPV Human papilloma virus causes genital warts: Around the urethral opening of the penis. On the shaft of the penis. On the scrotum. On the vulva. On the walls of the vagina. In the cervix. On the anus. 1-9

10 HPV The majority of people infected with HPV are asymptomatic. HPV is the single most important risk factor for cervical cancer. Also associated with cancer of the penis and the anus. Individuals infected by oral sex have an increased risk of cancers of the mouth and throat. 1-10

11 Diagnosing and Treating HPV Diagnosis is done by inspecting the warts or analyzing DNA of the patient. Several treatments are available: Podophyllin acid or bichloroacetic acid - applied directly to the warts Cryotherapy - warts are frozen off Laser therapy can also be used to destroy the warts. Several vaccines are currently being tested. 1-11

12 Genital Herpes A disease of the genital organs caused by a herpes simplex virus (HSV-1or HSV-2). 22% of Americans 12 years or older (45 million people) are infected by genital herpes. Symptoms - small, painful bumps or blisters Usually found on the vaginal lips, penis, or anus 1-12

13 Genital Herpes: Treatment Drug acyclovir prevents or reduces recurring symptoms, but there is no cure. Valacyclovir and famciclovir are new drugs that are even more effective at shortening outbreaks and suppressing recurrences. Scientists are actively working to create an immunization against herpes. 1-13

14 Herpes: Possible Complications Meningitis Narrowing of the urethra due to scarring Increased risk of becoming infected with HIV Transfer of virus from mother to infant in childbirth 1-14

15 Psychological Aspects: Coping with Herpes Psychological consequences need to be taken as seriously as the medical consequences. In one study 9% of women and 19% of men with herpes reported feelings of isolation and loneliness. One highly effective treatment program combines information on herpes, relaxation training, stress management training, and imagery technique. 1-15

16 Gonorrhea Also called the clap or the drip Caused by a bacterium Oldest of the sexual diseases Symptoms: Men: pus-like discharge and painful, burning urination Women: asymptomatic 1-16

17 Gonorrhea: Diagnosis 1-17 Men: Sample of discharge is examined. A urine test is also available. Women: Cervical discharge is taken and cultured. A pelvic exam should also be performed in women. Both: A swab from the throat or rectum should be taken and cultured if necessary.

18 Gonorrhea: Treatment The traditional treatment was a large dose of penicillin or tetracycline. Ceftriaxone is highly effective antibiotic, even against resistant strains. 1-18

19 Syphilis Caused by the treponema palliduma bacterium. Incidence is much less than that of gonorrhea or chlamydia. Can damage the nervous system and even cause death. Syphilis infection makes one more vulnerable to HIV and vice versa. 1-19

20 Syphilis: Symptoms and Progress Major early symptom - chancre A round, ulcerlike lesion with a hard, raised edge, resembling a crater Syphilis proceeds in stages: Primary-stage syphilis Secondary-stage syphilis Latent syphilis Late syphilis Congenital syphilis - passed from mother to infant 1-20

21 Syphilis: Diagnosis and Treatment Diagnosis: Physical exam; examination of fluid from chancre VDRL - fairly accurate blood test; cheap and easy to perform Treatment - antibiotics Penicillin, tetracycline, or doxycycline Total elimination of syphilis seems to be a feasible goal. 1-21

22 HIV Infection and AIDS AIDS - acquired immune deficiency syndrome HIV - human immune deficiency virus; the virus that causes AIDS. Opportunistic diseases make take over once HIV has damaged an individual s immune system. 1-22

23 HIV and AIDS: An Epidemic? By the start of 2003, more than 886,000 persons in the U.S. had been diagnosed with AIDS; 500,000 had died from it. It is estimated that one million are infected with HIV. In the early years of the U.S. epidemic, gay male sex accounted for the majority of cases. Today, women are the fastest growing group for new HIV infection. 1-23

24 HIV/AIDS Transmission Exchange of body fluids Contaminated blood and needles From infected woman to baby during pregnancy, childbirth, or breastfeeding 1-24

25 Sex and HIV/AIDS Transmission Anal intercourse is the sexual behavior most likely to spread AIDS. Heterosexual, penis-in-vagina intercourse spreads HIV as well. The greater your number of sexual partners, the greater your risk of getting infected with HIV. Condoms are 87% effective in protecting against HIV transmission during heterosexual intercourse. 1-25

26 The HIV Virus HIV is one of a group of retroviruses Retroviruses reproduce only in living cells of the host species, in this case humans. HIV invades a group of white blood cells (lymphocytes) called T-helper or T4 cells. These cells are critical to the body s immune response in fighting off infections. When HIV reproduces, it destroys the infected T cell. 1-26

27 HIV/AIDS: The Disease The Centers for Disease Control has established 4 classes of HIV infection: Initial infection Asymptomatic carrier state Lymphadenopathy - symptoms develop AIDS 1-27

28 HIV: Diagnosis Two major tests for HIV infection: ELISA (enzyme-linked immunosorbent assay) - blood test that detects the presence of antibodies to HIV Produces a substantial number of false positives. Western blot or immunoblot method Highly accurate though more expensive and difficult to perform. 1-28

29 HIV Diagnosis: Waiting Period ELISA test involves a waiting period of more than a week before results are known. OraQuick rapid HIV test for blood and OraQuick rapid HIV test for oral fluid both provide test results in 20 to 30 minutes. Both tests must be done in clinics. 1-29

30 HIV/AIDS: Treatment No cure for AIDS. AZT (azidothymidine zidovudine, ZDV) stops virus from multiplying. DDI (dideoxyinosine or didanosine) slows the progression of the disease. DDC (dideoxycytidine) stops the virus from replicating. 1-30

31 HIV/AIDS: Treatment Protease inhibitors - attack the viral enzyme protease, which is necessary for HIV to make copies of itself and multiply. HAART (highly active anti-retroviral therapy) Patients take a drug cocktail of protease inhibitor combined with AZT and another anti-hiv drug. Helping persons survive much longer Concern about the emergence of resistant strains 1-31

32 Women, Children, Ethnic Minorities, and AIDS HIV/AIDS is now the fifth leading cause of death for U.S. women between the ages of 25 and 44. Third leading cause of death for African American women. Intervention programs should include sexual assertiveness training, in which women are empowered to insist that their sex partners use condoms. 1-32

33 Women, Children, Ethnic Minorities, and AIDS Children become infected: From an infected mother at birth (89%) Because of hemophilia (4%) From transfusions of contaminated blood (6%) 1-33

34 Women, Children, Ethnic Minorities, and AIDS African Americans 12% of population 39% of AIDS cases Hispanics 13% of the population 27% of AIDS cases Asian Americans and Native Americans have less than 1% of cases. 1-34

35 Women, Children, Ethnic Minorities, and AIDS Many African Americans see AIDS as a planned strategy to kill African Americans. Culturally sensitive education and prevention programs that focus on the elimination of needle sharing an unsafe sexual practices should be developed for the black and Latino communities. 1-35

36 HIV/AIDS: Psychological Considerations Many patients experience a reaction that is a typical response to receiving a diagnosis of incurable disease Denial of the reality Anger Depression AIDS is a socially stigmatized disease. 1-36

37 HIV/AIDS: Psychological Considerations Cognitive-behavioral therapy combined with stress-management therapy has been shown to be effective in improving quality of life and decreasing anxiety and infection in HIV-infected people. Social and psychological support is essential. 1-37

38 Recent Progress in AIDS Research Vaccine Researchers are working to develop a vaccine, but this is more difficult than was expected. Research on Nonprogressors HIV-infected people who go for 10 years or more without symptoms are being studied. They have high levels of chemokines (HIVsuppressor factors) which can block HIV from entering cells. 1-38

39 Recent Progress in AIDS Research Studying people who resist infection may also yield clues to a vaccine or a cure. Some researchers believe that HIV s property of rapid mutation could be used against it by forcing it to mutate to a harmless form. 1-39

40 Recent Progress in AIDS Research Much effort going into developing effective microbicides that will attack HIV as well as other sexually transmitted viruses. In the last analysis, prevention is better than cure. 1-40

41 Viral Hepatitis There are 5 types of viral hepatitis but hepatitis B is of most interest in a discussion of STDs. People with long-term hepatitis B may develop serious liver disease involving cirrhosis or cancer. Treatment - rest, symptom relief, antiviral treatments Prevention - vaccine for hepatitis B. 1-41

42 Trichomoniasis Caused by Trichomonas vaginalis protozoan. Transmitted mainly through sexual intercourse. Occasionally transmitted nonsexually - organism can survive on toilet seats and other objects Can lead to pelvic inflammatory disease and problems with birth. 1-42

43 Pubic Lice (Crabs) Tiny lice - that attach to the base of pubic hairs and feed on blood from their human host. Symptom - itching Treatment - Nix and Rid are both available without prescription. 1-43

44 Other Genital Infections Vaginitis - vaginal inflammation or irritation. Monilia (candida) - yeast infection Bacterial vaginosis Cystitis - infection of the urinary tract or bladder in women. Prostatitis - inflammation of the prostate gland. 1-44

45 Preventing STIs Abstain from sexual activity. Limit oneself to monogamous relationship with an uninfected person. Condoms can help. Careful washing and inspecting of genitals. Urinating before and after intercourse helps keep bacteria out of the urethra. 1-45