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Psychology 2075
Corey Isaacs

Psychology 2075 Chapter 8 Notes (Pg.200-223) Sexually Transmitted Infections Introduction  STD refers only to infections causing symptoms  STI is more encompassing because it includes infections for which people have symptoms as well as those for which they have no symptoms  Worldwide of the 60 million people who have been infected with HIV, about half become infected between the ages of 15 and 24  STI-related stigma refers to an individual’s awareness that people will judge them negatively for having an STI  STI-related shame refers to the negative feelings people have about themselves when they receive an STI diagnosis  People with higher STI-related stigma and shame are less likely to be tested or screen for STIs Chlamydia  Chlamydia trachomatis is a bacterium that is spread by sexual contact and infects the genital organs of both males and females  Chlamydia has become the most prevalent bacterial sexually transmitted infection in Canada  When an individual consults a physician because of a urethral discharge his chances of having chlamydia are greater than this chances of having gonorrhea  This is important since chlamydia does not respond to the drugs used to cure gonorrhea Symptoms  Main symptoms in men are a thin, usually clear discharge and mild discomfort on urination appearing 7 to 21 days after infection  Symptoms are somewhat similar to the symptoms of gonorrhea in men, however gonorrhea tends to produce more painful urination and a more profuse pus-like discharge  Diagnosis is made from a urine sample in men and from a sample of cells from the cervix (or urine sample) in women  75% of the cases of chlamydia infection are asymptomatic in women while among men they are about 50% asymptomatic Treatment  Chlamydia is treated with azithromycin or one of the tetracyclines, it does not respond to penicillin  Poorly treated or undiagnosed cases may lead to urethral damage, epididymitis, Reiter’s syndrome, and proctitis in men who have had anal intercourse  Women with untreated or undiagnosed chlamydia may experience serious complications if not treated: pelvic inflammatory disease (PID) and possible infertility due to scarring of the fallopian tubes  A baby born to an infected mother may developed pneumonia or an eye infection Prevention  Goal of developing vaccine that would prevent infection  Vaccines have been developed that are effective in mice but certain technical obstacles prevent their use in humans  One of the most effective tools for prevention is screening since many people are asymptomatic and spread the disease unknowingly  Recommended that doctors routinely test all sexually active women under the age of 25 however most do not do so  In rural Nova Scotia, self-test screen kits were made available in a private setting to all high school girls  Anonymous self-testing is a promising method for screening individuals who would not see a medical professional for testing  On individual level best method for prevention is using a condom HPV  There are more than 40 different types of the human papillomavirus that are sexually transmitted  Some types cause genital warts and are low risk as they do not cause cancer while other types cause cervical cancer and are high-risk types  Some types have no symptoms at all, most cases are asymptomatic  HPV is not a reportable disease and so there’s no national Canadian data  It is estimated that between 20 and 33 percent of women have HPC and between 11 and 25 percent of women have the cancer causing type of HPV  Highest rate of HPV is usually among women under 25  Highly infectious disease, risk reduced but not diminished by condoms  It is transmitted through skin-to-skin contact most often from contact with the penis, scrotum, vagina, vulva or anus of the infected person  Genital warts are cauliflower-like warts appearing on the genitals, usually around the urethral opening of the penis, the shaft of the penis, or the scrotum in the male, and on the vulva, the walls of the vagina, or the cervix in the female; warts may also occur on the anus  Typically, these warts appear about 3-8months after intercourse with an infected person  HPV also causes almost all cases of cervical cancer, HPV 16 and 18 account for 70 percent of the cases of cervical cancer and HPV infection is also associated with cancer of the penis and anus  It can also be transmitted orally, those infected this way have an increased rate of oral cancers Diagnosis  Diagnosis through inspecting the warts and for women first indication is abnormal cells on a pap test Treatment  For the warts themselves, chemicals such as podophyllin or trichloroacetic acid can be applied to the warts. Aldara can also be used. These treatments are usually repeated several times and the warts then fall off  Cryotherapy involves freezing the warts off  Many cases of HPV infection go away on their own but others persist for long periods of time, risk of cervical cancer increases with longer infections Vaccine  Vaccine against HPV prevents most cases of cervical cancer  Gardasil protects against four HPV types that between them cause 70 percent of cervical cancers and no percent of genital warts o It is administered with 3 shots over a six-month period  Immunity lasts atleast 5 years, probably more  Cervarix is a newer vaccine that protects against two HPV types that cause 70 percent of cervical cancers Genital Herpes  Genital herpes is a disease of the genital organs caused by the herpes simplex virus (HSV)  It is transmitted by sexual intercourse and by oral-genital sex  Two strains of HSV are circulating: HSV-1 and HSV-2  In the past, HSV-2 caused genital herpes and HSV-1 caused cold sores around the mouth but today there is more crossing over  Genital herpes then can be caused by either HSV-1 or HSV-2  Estimated that more than 20% of Canadian adults are infected o Ex. In BC the rate of HSV-2 among women is 17% o The rate increases with age, reaching 28% by age 44 o Rate of HSV-2 is lower among women in Ontario than in BC reaching 16% by age 44  Rates higher among individuals who have had more sexual partners  Of those that test positive for HSV-2 in their blood, only 14% report having been diagnosed with herpes  Of those with HSV-1 in their blood but not HSV-2, 2% report having diagnosed with genital herpes  The great majority of people with HSV are asymptomatic and are not aware that they are infected, these people transmit the disease to others unknowingly Symptoms  Symptoms of genital herpes caused by HSV-2 are small, painful bumps or blisters on the genitals  Typically they appear within 2 or 3 weeks of infection o In women they are usually found on the vaginal lips; in men, they usually occur on the penis o May appear around anus if the person has had anal intercourse o The blisters can burst and be quite painful o Fever, painful urination and headaches may occur o The blisters heal on their own in about 3 weeks in the first episode of infection o The virus continues to live in the body, but may remain dormant for the rest of the person’s life o But the symptoms may recur unpredictably, so that the person repeatedly undergoes 7-14 day periods of sores o HSV-1 infection tends to be less severe  People with herpes are most infectious when they are having an active outbreak  People are infectious even when there is no outbreak or if they have never been symptomatic, so there is no completely safe period Treatment  Currently, there is no cure; no known drug that kills the virus  Researchers are pursuing two solutions: drugs that treat symptoms in someone who is already infected and vaccinations that prevent herpes  Acyclovir (Zovirax) prevents or reduced the recurring symptoms although it does not cure the disease  Valacyclovir (Valtrex) and famciclovir (Famvir) are newer drugs that are even more effective at shortening outbreaks and suppressing recurrences  These drugs reduce the rates of transmission from an infected partner to an uninfected one  Scientists are actively working to create a method for immunization against herpes Long-Term Consequences  Men or women with recurrent herpes may develop complications such as meningitis or narrowing of the urethra due to scarring, leading to difficulty with urinating  Most people with herpes are not affected by this though  Another complication is that herpes increases one’s risk of becoming infected with HIV (open blisters make it easy for HIV to enter the body)  Other complication is transfer of the virus from mother to infant in childbirth, which in some cases leads to serious illness or death in the baby  Risk of transmission is highest in women who have recently been infected and are having their first outbreak  C-Sections are usually preformed on women with an outbreak Psychological Aspects: Coping with Herpes Those who are unaware they have the disease are still happily sexually active not knowingly spreading the disease to others. At the same time there are those persons who experience frequent, severe, painful recurrences. Many people with herpes feel stigmatized because of their disease and believe they should abstain from sex to avoid infecting others. HIV Infection and AIDS  First AIDS case in Canada was reported in February 1982  Stands for Acquired Immune Deficiency Syndrome  The virus that causes AIDS, HIV was identified in 1984 and another strain of the virus; HIV-2 has been identified and is found almost exclusively in Africa while HIV-1 accounts for almost all infections in North America  HIV destroys the body’s natural system of immunity to diseases An Epidemic?  By end of 2008, 21300 persons in Canada had been diagnosed as having AIDS and 63% had died from it  Estimated that 33 million people worldwide are infected with HIV  However, as the number of people with HIV worldwide continues to grow, the number of new infections each year has been decreasing Transmission  HIV is spread in four ways: o By Sexual Intercourse o By contaminated blood o By contaminated hypodermic needles o From an infected woman to her baby during pregnancy and childbirth  Statistics indicated that Canadians with HIV/AIDS are: o 56% men who have sex with men o 18% people who inject drugs o 2% men who have sex with men and use injection drugs o 18% heterosexuals who have had sexual contact with infected individuals o 2% recipients of contaminated blood transfusions o 1% at birth from an infected mother o Most likely to be exposed to HIV in early 20s  Worldwide, 70% of the cases result from heterosexual transmission  The sexual activity most likely to spread HIV is anal intercourse, receiving partner puts one most at risk o True for both men and women regardless of sexual orientation  Statistically, the greater your number of sexual partners, the greater your risk of getting infected with HIV  Penile-vaginal or anal intercourse is riskier if it is with a person who is infected with HIV, has engaged in high-risk behaviours, is hemophiliac, is from a country where there is a high rate of HIV infection, or if condoms are not used.  Cumulative risk is the likelihood of contracting an STI after repeated unprotected exposure The Virus  HIV is one of a group of retroviruses  Retroviruses reproduce only in living cells of host species (humans)  Invade host cell, each time host cell divides, copies of the virus are produced along with more host cells, each containing genetic code of the virus  Current research is aimed at finding drugs that will prevent the virus from infecting new cells, two strains of HIV in NA, HIV-1 and HIV-2  Several subgroups of HIV-1 that differ genetically  HIV particularly invades a group of white blood cells called CD4+ T-lymphocytes  T-Cells are critical to body’s immune response fighting off infections  When HIV reproduces, destroys infected T cell  Eventually number of T cells is so reduced that infections cannot be fought off  Two coreceptors for HIV, CCR5 and CXCR4 which allow HIV to enter T cells  CCR5 important coreceptors in early stages while CXCR4 important in later stages The Disease Four broad classes of manifestations of HIV infection: 1. Primary Infection: begins with the initial infection with the virus and development of antibodies to it over the next 2-8 weeks. No immediate symptoms, usually starts with fever or sore throat. Stage lasts as long as the person keeps feeling well and T4 cell count stays around 100 cells per cubic millimeter of blood, can still infect people at this stage. 2. Asymptomatic Infection: Infected with virus, show no symptoms, lymphadenopathy frequently present. Symptoms such as swollen lymph glands and night sweats not immediately life-threatening, these asymptomatic carriers can infect other persons. 3. Progressive infection: Conditions that indicate immune system is sufficiently repressed and unable to fight off infections. Many infected persons go on to develop symptoms such as fever, chronic diarrhea, unexplained weight loss, fatigue, chronic yeast infections, shingles, or abnormal or cancerous cell in the cervix. T4 cell count drops by half (500), immune system silently failing. Treatment with AZT, DDI, and other drugs may begin at this time. 4. AIDS-defining opportunistic infection: diagnosis of AIDS applied when person is affected by life-threatening opportunistic infections such as Pneumocystis carinii pneumonia (PCP) and Kaposi’s sarcoma (KS), a rare form of skin cancer. Diagnosis also used when cancers of lymph tissue are present and person shows positive test for HIV antibodies. Virus can infect cells of the brain; symptoms then include seizures and mental problems. T cell count below 200 is by itself an indication of AIDS. Diagnosis  Blood test detects presence of antibodies to HIV using ELISA (enzyme-linked immuno-sorbent assay) technique. Easy and cheap. o Can be used to screen all donated blood in Canada o Helps people determine if they are HIV positive but asymptomatic carrier  This is important because if people suspect they are infected and find out through blood test they are they need to be responsible  ELISA is a highly accurate test, but it does produce a small number of false positives – saying HIV antibodies are present when they really aren’t  Positive ELISA test should always be confirmed by a 2 more specific test  Other major test is using Western blot or immunoblot method o More expensive and difficult to perform, not practical for mass screening of blood as ELISA is o Highly accurate, useful in confirming positive test from ELISA  Both tests only detect presence of HIV antibodies, do no predict whether person will develop symptoms or will progress to AIDS classification  Drawback to ELISA test is that it has a long waiting period  Rapid test approved for use in Canada, takes 60 seconds and only detects antibodies to HIV-1, only intended as a screening test  Now a home test kit for HIV available in the US but not in Canada, involves finger prick and then dried blood spots are mailed to a laboratory for anonymous testing Treatment  Not yet any cure for aids, but AZT has been used widely as it stops the virus from multiplying  It cannot repair the person’s damaged immune system and has many side effects, cannot be used by some people, or can only be used for limited periods of time  Effort to find new drugs that will slow or stop progression of the disease  DDI (dideoxyinosine or didanosine) and DDC (dideoxycytidine) are two examples  Slow progression of the disease by preventing replication of the virus  D4T is a similar drug, collectively these drugs are called ART (antiretroviral therapy)  Major breakthrough came in 1996, protease inhibitors  These inhibitors attack the viral enzyme protease which is necessary for HIV to make copies of itself and multiply  Second breakthrough came in 2006, darunavir, a drug that acts on viruses that are resistant to the protease inhibitors  Most patients today take a “drug cocktail
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