HSC4711 Exam 3 Study Guide Sexually Transmitted Diseases diseases that can be transmitted by sexual contact and some can also be transmitted by other means o a person can be infected and able to transmit the disease but not feel sick or show any symptoms o can also be called Sexually Transmitted Infections for this reason STIs can be cured o STDs that pose a major health threat HIV AIDS Hepatitis Gonorrhea Syphilis Chlamydia Herpes Human Papillomavirus HPV risks to a fetus or newborn o long term co0nsequences chronic infertility stillbirths genital cancers death o these diseases are serious in themselves cause serious complications if left untreated and pose o US has highest rate of STDs in all developed countries o half of all young people will acquire an STD by age 25 o 65 million Americans infected with an STD o 19 million Americans newly infected each year HIV AIDS o HIV human immunodeficiency virus causes HIV infection and AIDS o AIDS acquired immunodeficiency syndrome disease that ultimately kills most victims especially in parts of world where treatment is not available incurable o 65 million people infected since epidemic began 1 world population and tens of millions of those people have died already o today 33 million infected worldwide and most of these people will die within 10 years o disease peaked in late 1990s o AIDS remains primary cause of death in Africa and continues to be a major cause of mortality o AIDS is leading cause of death worldwide for people 15 59 o 1 1 million people in US have been infected with HIV and 56 000 new HIV infections reported worldwide in 2006 o 550 000 Americans died from AIDS since start of epidemic in 1981 but death rate among Americans has declined estimated 3 million infections per year o 21 25 of infected people are unaware of their condition o HIV Infection chronic progressive viral infection that damages the immune system makes an otherwise healthy person less able to resist variety of infections disorders HIV attacks immune system invading monocytes macrophages and CD4 T cells type of white blood cell that helps coordinate activity of immune system frontline of immune system helper T cells primary target for HIV infection travels in blood and lymph HIV enters human cell and converts its own genetic material RNA into DNA which is then inserted into chromosomes of host cells viral DNA takes over CD4 cell causing it to make new copies of HIV as well as making the CD4 cell incapable of performing its immune functions eventually the immune isn t able to make enough new cells to keep up with the rapidly growing infected cells immune system destruction is signaled by loss of CD4 T cells as CD4 cells decline a person may notice mild to moderately severe symptoms full blown AIDS when a person develops one of the conditions defined as a marker for AIDS or when number of CD4 T cells in blood drops below 200 l HIV causes AIDS after an average of about 11 years people with AIDS vulnerable to serious opportunistic secondary infections infection caused when organisms take opportunity presented by a primary initial infection to multiply and cause a new different infection TB pneumonia stages of infection primary infection phase first weeks after being infected large amounts of HIV in blood stream making them incredibly infections flulike symptoms asymptomatic symptom free chronic can last from 2 20 years average is 11 virus progressively infects and destroys cells of immune system o HIV is transmitted by blood blood products semen vaginal secretions cervical secretions and breast milk lives only within cells and body fluids not outside body can t live in air water or on surfaces objects toilet seats eating utensils telephones three main routes of transmission specific kinds of sexual contact direct exposure to infected blood sharing needles piercings HVI infected woman to her fetus during pregnancy or childbirth or to her infant during breastfeeding more likely to be transmitted by unprotected anal or vaginal intercourse male to female transmission more likely because female has much more surface area of mucous membranes and higher chance of tear or lesion transmission can also happen before ejaculation because HIV has been found in preejaculatory fluid being receptive partner in unprotected anal sex is extremely risky oral genital contact carries some risk but less than anal or vaginal intercourse presence of lesions blisters or inflammation from other STDs in genital anal or oral areas increase likeliness for transmission 2 9 times spermicides may also increase risk of HIV transmission risk of transmission increases during oral sex if poor dental hygiene oral sores brushed flossed before or after oral sex circumcised males have lower risk than uncircumcised males nearly 20 of all new US cases of HIV caused indirectly or directly by sharing drug injection equipment contaminated with HIV also transmitted in blood and blood products used in medical treatment of injuries and illnesses 14 000 cases of AIDS in US mother to child transmission is called vertical or perinatal transmission 25 30 of infants born to untreated HIV infected mothers are also infected with virus o Populations of special concern for HIV infection most common means of HIV exposure is sexual activity between men next most common are heterosexual contact and injection drug use IDU high rates of infection in certain groups tied to social cultural and economic factors 75 of HIV positive Americans are men 25 women increasingly becoming a disease that affects ethnic minorities women and the poor African American men and women are vastly overrepresented among people newly diagnosed with AIDS also men who have sex with men are at large risk young gay men less likely than older gay men to have experienced watching friends die from AIDS and so are more removed from reality of disease young men may be less afraid of acquiring HIV because of advances in treatment and a false belief that cure is just around the corner men who have sex with men but still identify themselves as heterosexual just as likely to be infected with HIV but much less likely to know HIV status and more likely to transmit it to male or female partner o Symptoms within a few days or weeks flulike symptoms primary HIV infection standard tests for HIV will usually be negative in early stages of infection so the HIV RNA assay must be used test to determine the viral load amount of HIV in the blood immediate treatment