Unit Four
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Presentation Transcript
Unit Four Reproductive System “STD’s”
General Information about STD’s • STD’s are caused by bacteria, viruses, or microscopic insects • Physical contact is required to pass an STD from one infected person to another (except Pubic Lice) • Some STD’s are curable with prompt treatment, but many are not, like Genital Herpes and HIV
General Information about STD’s • Just as Abstinence is 100% effective at preventing unwanted pregnancies, it is also 100% effective at preventing the passage of STD’s • Other than abstinence, a condom (male or female) is the only other fairly reliable method that protects against the passage of STD’s
STD’s of Bacterial Origin • Bacteria are Prokaryotes (single-cell organisms) • Within the single cell that comprises a bacterium, there is DNA, a cytoplasm that contains enzymes and ribosomes, and finally, a plasma membrane that surrounds all its contents • Whether a person acquires a bacterial infection through sexual intercourse or eating improperly prepared food, the infection can be treated with antibiotics
STD’s of Bacterial Origin • It is always important to take all the antibiotics prescribed in order to totally eradicate the bacteria from one’s body • If a person does not take all the antibiotics prescribed, the bacteria may not be eradicated/killed, and additionally may become resistant to those same antibiotics • The above can translate into a very difficult to kill bacterial infection
STD’s of Bacterial Origin • Chlamydia • Caused by bacterium: Chlamydia trachomatis • Infects and grows within the cells of the body • Leading STD in the USA • It is often asymptomatic • Symptoms: • Men – burning sensation when urinating and mucoid discharge • Women – vaginal discharge and UTI symptoms; left untreated can cause sterility – PID (Pelvic Inflammatory Disease)
Chlamydia • Chlamydia can cause inflammation of the eye in adults and newborns Erythromycin eye drops are used to prevent newborns from contracting the eye infection
STD’s of Bacterial Origin • Gonorrhea • Caused by bacterium: Neisseria gonorrhoeae • Rates of infection have increased in recent years • Persons with gonorrhea often get infected with chlamydia and/or HIV • Can be asymptomatic • Symptoms • Men: pain during urination and milky discharge 3 to 5 days after contact with pathogen • Women: most women are asymptomatic until the bacteria settles in the uterus/fallopian tubes – onset of PID
Gonorrhea • Example of PID caused by Gonorrhea; can lead to female infertility, ectopic pregnancy, and chronic pelvic pain
STD’s of Bacterial Origin • Syphilis • Caused by bacterium: Treponema pallidum • It is a corkscrew-like organism • It has three stages: • Primary – ulcer indicates site of infection • Secondary – rash on hands and feet • Tertiary – lasts until the patient dies; bacteria infect the central nervous system and the heart, large ulcers develop on the skin
STD’s of Viral Origin • Viruses are not capable of independent reproduction, and therefore require a host cell to enable them to reproduce • Viruses are referred to as Obligate Intracellular Parasites • Viruses are very specific as to the type of cells they will infect; they are smaller than bacteria and are not considered cellular organisms • They always have two main parts: an outer capsid (wall/barrier), and DNA/RNA on the inside of the capsid
STD’s of Viral Origin • Once a virus infects a cell, it begins to make numerous copies of itself and hence leave the host cell through the process known as Budding • Some viruses can become Latent: period of inactivity • While latent, the viral genes are integrated into the host DNA, and are subsequently copied whenever the host cell divides
STD’s of Viral Origin • Viral diseases are controlled by preventing transmission, administering vaccines, and recently by administering antiviral drugs (interferes with entry of virus into host cell, replication of its DNA/RNA, or exit of the virus from the host cell)
STD’s of Viral Origin • Herpes Simplex Viruses • HSV-1: causes cold sores and fever blisters • HSV-2: results in genital herpes • Tingling/itching sensation • Blisters that rupture into ulcers • Fever, pain on urination, ample vaginal discharge • Can cause blindness, neurological disorders, and death of infants that encounter the infection in the vaginal canal during birth ****No cure for Genital Herpes
STD’s of Viral Origin • Genital Warts • Human papillomaviruses (HPV’s) cause all warts, including genital warts, which are sexually transmitted • Many have genital warts but do not get treatment; either is asymptomatic or symptoms are not severe • Symptoms • Warts develop on the penis and foreskin of men and near the vaginal opening of women • Women who have genital warts can develop cervical cancer • Men and women who have genital warts can develop tumors of the anus and mouth *** No cure for Genital Warts
STD’s of Viral Origin • Hepatitis • Several types of Hepatitis: A, B, C, and E • Hepatitis A – contracted through sewage contaminated drinking water or oral and anal contact; symptoms include tiredness, fever, sore muscles, headache, nausea, yellow skin • Hepatitis C – contracted through blood transfusions and can lead to chronic hepatitis, liver cancer, and death
STD’s of Viral Origin • Hepatitis continued • Hepatitis E – occurs in developing countries and then is brought back to USA by travelers who visited developing countries; usually mild disease and symptoms can include abdominal pain, nausea, fatigue, poor appetite, and dark urine • Hepatitis B – is a DNA virus spread in the same way as HIV through sharing needles and unprotected sex; it is common for an AIDS patient to also have Hepatitis B; symptoms are similar to those of the flu, and can lead to the need for a liver transplant if symptoms are chronic **** No cure for Hepatitis viruses
Hepatitis B Diseased liver of a person with chronic Hepatitis B
Other Infections • Vaginal Infections • Bacterial Vaginosis (BV) • Males pass excess amounts of a bacterium called, Gardnerella vaginalis to the female during intercourse • Excess amounts of this bacterium causes a decline in lactobacilli, and hence, a change in the pH of the vagina • Symptoms include foul odor coming from vagina after sex and a thin gray discharge • BV can increase the risk of PID and HIV infections
Other Infections • Vaginal Infections continued • Trichomoniasis • Caused by protozoan Trichomonas vaginalis • 5 million new cases each year in the USA • Usually acquired by females through sexually intercourse with an asymptomatic male • Symptoms include heavy frothy, white foul-smelling vaginal discharge from the vagina, and severe itching • Can lead to cervical cancer if left untreated
Trichomoniasis Trichomonas vaginalis
Other Infections • Pubic Lice aka “Crabs” • Parasitic crab louse Phthirus pubis, resembles a small crab and inhabits the pubic hair of humans • Can be contracted through direct physical contact or contact with infected person’s clothes or bedding • Females of the species lay many eggs near the base of each hair and hatching occurs in a few days • Main symptom is severe itching around pubic area due to removal of blood from the host human by each crab louse • Can self treat with topical cream
HIV/AIDS • History • First documented in January of 1981 by the Center for Disease Control • Thought to have spread to the USA by a gay flight attendant who traveled abroad • Originally called the “Gay Cancer” and/or “Gay Plague” because the initial outbreak was mainly confined to homosexual males
HIV/AIDS • History continued • Less than a year later the list of at risk individuals expanded to include intravenous drug users, recent Haitian immigrants, and Hemophiliacs regardless of sexual orientation • The virus that causes AIDS was first discovered by a French scientist in 1983 • Circa 1987, Rock Hudson announced he had AIDS and died shortly after
HIV/AIDS • History continued • In the 1990’s heterosexual celebrities and professional athletes announced they too had acquired HIV: Magic Johnson and Arthur Ashe • The 1990’s saw large amounts of research dedicated to treatment drugs and finding a cure • Currently there are some very effective drugs to treat HIV and keep it from developing into AIDS • Majority of new cases are in Sub-Saharan Africa, and unfortunately those people lack the finances to pay for those drugs to treat HIV
HIV/AIDS • Three phases of the disease • Acute Phase • Virus infects person (host) and replicates ferociously • Replication process causes death of lymphocytes in the person’s blood • Person may be asymptomatic for several weeks; if person does have symptoms they include fever, chills, aches, swollen lymph nodes, and an itchy rash • After many weeks the person’s body reacts to the foreign invader by producing numerous immune cells to fight the virus
HIV/AIDS • Chronic Phase • Several months to several years an untreated individual will most likely progress to this phase • Number of HIV viruses increases causing reemergence of symptoms like fatigue, persistent fever, night sweats, persistent cough, and persistent diarrhea • These symptoms are a signal that full blown AIDS will develop soon
HIV/AIDS • AIDS • Lymphocyte count has dropped drastically; viruses have taken over the blood • Person is extremely weak and thin due to persistent diarrhea and coughing • Person eventually dies due to the presence of another infection • People do not die from AIDS, but rather, Acquired Immune Deficiency Syndrome weakens their bodies ability to fight other common infections *** There is currently no cure for HIV/AIDS