Chapter 18: Sexually Transmitted Infections

coreceptors for HIV

-CCR5 and CXCR4 which allow HIV to enter T cells -CCR5 seems to be important coreceptor in early stages of the disease and CXCR4 in the later stages -the discovery of coreceptors may lead to advances in treatment if drugs can be used that block these coreceptors

what percentage of HPV infections are asymptomatic and go away by themselves within 2 years?

-about 90%

genital warts

-cauliflower-like warts appearing on genitals usually around urethral opening of penis, shaft of penis, scrotum, on vulva, on walls of vagina, on female cervix, sometimes on anus -warts appear 3-8 months after intercourse with an infected person

what percentage of americans are infected with HSV-2?

-16%

HIV transmission

-HIV is transmitted by exchange of body fluids (semen, blood, and possibly secretions of cervix and vagina)

pediatric aids

-children can become infected at birth from infected mother -the use of antiretrovirals to treat infected women during pregnancy has reduced the rate of infection in babies -in the united states, AIDS in infants is nearly eliminated -people of color in america and worldwide bear a disproportionate burden of AIDS cases

coping with herpes

-high range of psychological responses -ppl with asymptomatic herpes aren't aware they have the disease and are happily sexually active -ppl who experience severe/frequent/painful recurrences feel stigmatized and may abstain from sex in order to avoid infecting others

human papillomavirus (HPV)

-increases the risk of certain cancers such as cervical cancer and causes genital warts -majority of people infected with HPV are asymptomatic

trichomoniasis symptoms for men

-irritation of the urethra and a discharge from the penis -some men are asymptomatic

asian american and native american incidence of AIDS

-low (less than 1% of cases) for each group

HIV and aids

-HIV (humane immune deficiency virus) causes AIDS -HIV destroys the body's natural system of immunity to diseases. once HIV has damaged an individual's immune system, opportunistic disease may take over and may even kill

psychotherapy in HIV/AIDS treatment

-HIV infected people who are being treated with ART who are also depressed have worse medical outcomes than those who are infected and not depressed -psychotherapy can reduce depression in infected people, improving quality of life and medical outcomes, as well as increasing their adherence to ART

how is HPV diagnosed?

-DNA test can be run on a sample of cells of the cervix to detect the types that are linked to genital cancers -for warts, diagnosis can be made simply by inspecting the warts if present as they have a very distinct appearance. some are harder to find though

how many deaths did HIV cause in 2012?

-HIV infection caused approximately 1.6 million deaths worldwide in 2012 alone, thus the term GLOBAL EPIDEMIC and pandemic have been used

diagnosis of syphilis

-difficult to diagnose because its symptoms are like other disease. physical exam should be done (whole body surface) and women should also have a pelvic exam. the most common tests for syphilis are blood tests that are based on antibody reactions. the VDRL is one of the blood tests that is fairly accurate, cheap, and easy to perform

genital herpes

-disease of genital organs cause by the herpes simplex virus (HSV) -two strains circulate: HSV-1 and HSV-2. HSV-1 used to cause cold sores around the mouth and HSV-2 used to cause genital herpes. however, the two are more interchangeable nowadays as genital herpes can be caused by either strain -transmitted by sexual intercourse and by oral-genital sex

treatment of candida

-drugs miconazole or clotrimazole both available over the counter -fluconazole, a single dose treatment, is available by prescription

symptoms of hepatitis b

-enlarged liver that is somewhat tender -disease can vary from asymptomatic to extreme symptoms (such as fever, fatigue, jaundice, vomiting)

HPV era (pre-vaccine) 2003-2006

-females aged 14-59, 43% were infected (not all were cancer-causing types) -12% of women had one of the cancer-causing types and this number went down to 5% after vaccines were invented

symptoms of prostatitis

-fever, chills, pain around anus/rectum, need for frequent urination -may produce sexual dysfunction, typically painful ejaculation

symptoms of pubic lice

-fierce itching in pubic hair area -diagnosis is made by finding the lice or the eggs attached to the hairs

asymptomatic gonorrhea

-occurs in males but not often. in contrast, about 50-80% of women infected with gonorrhea are asymptomatic during the early stages of the disease -many women are unaware of their infection unless they are told by a male partner -because so many women are asymptomatic during early stages of gonorrhea, many don't get treatment and there is a high risk of serious complications. in about 20% of women who go untreated, the gonococcus moves up into the uterus. from there it infects the fallopian tubes. the tissues become swollen and inflamed and the condition is called PID (pelvic inflammatory disease) -untreated gonorrhea is one of the most common causes of infertility in women

progress of syphilis

-once infected, the progress of the disease in a person is divided into four stages: primary stage syphilis, secondary stage syphilis, latent syphilis, and late syphilis

what percent of sexually active adolescent girls have an std?

-one in four (25%) -HPV (human papillomavirus), trichomoniasis, and chlamydia account for the great majority of these cases

druck cocktail

-patients take drug cocktail nowadays of a combination of all drugs mentioned before -this is called ART for antiretroviral treatment -many patients take only a single combo pill per day with relatively minor side effects -ART has made HIV infection a manageable disease (somewhat like diabetes) with many HIV-infected individuals now expected to survive into their 70s -drugs are also being formulated that prevent opportunities infections that strike people with AIDS (the drug pentamidine can be used to prevent pneumocystis carinii pneumonia)

treatment of syphilis

-penicillin -treponema pallidum is fragile so large doses of penicillin aren't necessary in treatment -recommended dose is two shots of penicillin G, one in each of the buttocks -latent, late, and congenital syphilis require larger doses -for people allergic to penicillin, the recommended treatment is tetracycline or doxycycline, but it should not be given to pregnant women

treatment of herpes

-no known drug that kills the virus (aka no cure) -researchers pursuing two solutions: drugs that treat symptoms in someone who is already infected and vaccinations that prevent herpes -the drug acyclovir prevents/reduces recurring symptoms. valacyclovir and famciclovir are never drugs that are even more effective in shortening outbreaks and suppressing recurrences. these drugs also reduce rates of transmission from infected to uninfected

gonorrhea

-"the clap," "the drip" -oldest of sexual diseases. its symptoms are described in the old testament (about 3,500 years ago) -hippocrates (greek physician) believed that gonorrhea resulted from excessive indulgence in the pleasures of venus (goddess of love) about 2,400 years ago -bacterium that causes gonorrhea: neisseria gonorrhoeae (identified in 1879) -always a prob during war time when it spreads rapidly among soldiers and prostitutes they patronize -during world war 1, a gonorrhea epidemic occurred and it was also a large problem during WW2 -with the discovery of penicillin, the disease became much less prevalent in the 1950s -most cases of gonorrhea result from penis in vagina intercourse

why did a resurgence of gonorrhea occur in 1970s?

-1 million cases reported per year in 1970s -a main reason for this was the shift in contraceptive practices to the use of the pill (which unlike the condom, provides no protection from gonorrhea and actually increases a woman's susceptibility)

how many new cases of syphillis in 2013?

-17,000 but rates have begun to rise again

how many gonorrhea cases per year nowadays?

-300,000 and the decline is likely due to increased use of condoms

what percentage of americans are infected with HSV-1?

-54% (the great majority are asymptomatic and do not know they are infected)

what percentage of chlamydia cases are asymptomatic in women?

-75% (among men, 50%)

stage 3

-AIDS -t cell count falls below 200 -people in this stage are vulnerable to opportunistic infections that can be life-threatening -opportunistic infections are ones that occur only in people with severely compromised immune systems (ex: rare form of pneumonia, rare form of skin cancer, and invasive cervical cancer)

what stds are frequent among college students?

-chlamydia, HPV (genital warts), and herpes

stage 2

-the t cell count falls to between 200 and 499

treatment for genital warts

-chemicals such as podophyllin or bichloroacetic acid (BCA) can be applied directly to warts (tx has to be repeated several times) -warts can be frozen off using liquid nitrogen (cryotherapy), which also typically requires several treatments -podofilox cream can be applied by the patient

the virus

-HIV is one of a group of retroviruses -retroviruses reproduce only in living cells of the host species, in this case humans -host cell is invaded and each time the host cell divides, copies of the virus are produced along with more host cells, each containing the 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 are found in the united states today (HIV-1 and HIV-2) and there are several subgroups of HIV-1 that differ genetically -HIV invades a specific group of white blood cells (lymphocytes) called CD4+ T-lymphocytes (T cells) -t cells are critical to the body's immune response in fighting off infections. when HIV reproduces, it destroys the infected t cell. eventually the HIV-positive person's number of t cells is so reduced that infections cannot be fought off

what does the latex condom protect against?

-HIV, HPV, gonorrhea, chlamydia, herpes, syphilis, and other STIs

what is the single most important risk factor for cervical cancer?

-HPV infection -there are more than 40 distinct types of HPV that are sexually transmitted -types 6 and 11 cause genital warts and are called "low risk" because they do not cause cancer -high risk types DO increase the risk of cervical cancer -HPV 16 and 18 account for 70% of the cases of cervical cancer -HPV infection is also associated with cancer of the penis and anus

AZT (azidothymidine)

-a drug used to treat HIV-infected people, also called ZVD -can stop virus from multiplying but it cannot repair the person's damaged immune system

trichomoniasis

-a form of vaginitis causing a frothy white or yellow discharge with an unpleasant odor -caused by the protozoan trichomonad vaginalis and organism can survive on toilet seats and other objects, so it is occasionally transmitted non sexually. it is, however, transmitted mostly through sexual intercourse -diagnosis has to be accurate because drugs that treat trichomoniasis are different than drugs used to treat other STIs that have similar symptoms -the long term effects of untreated trichomoniasis can be serious

candida

-a form of vaginitis causing a thick, white discharge; also called moniliasis or yeast infection -normally present in vagina but if delicate environmental balance there is disturbed (ex: ph changes), then the growth of candida can get out of hand -conditions that encourage growth of candida: long term use of birth control pills, menstruation, diabetes/prediabetic condition,pregnancy, and long term use of antibiotics such as tetracycline -not a sexually transmitted infection, but intercourse may aggravate it -another vaginal infection that produces a similar discharge but with a foul oder: bacterial vaginosis

hepatitis b

-a liver disease that can be transmitted sexually or by needle sharing -virus can be transmitted through blood, saliva, semen, vaginal secretions, and other body fluids -behaviors that spread hep b: needle sharing by ppl who inject drugs, vaginal/anal intercourse, oral-anal -disease is found among men who have sex with men and among heterosexuals -many similarities to aids, but hepatitis b is more contagious. people who have had the disease continue to have a positive blood test for it for the rest of their lives -many adults infected with HBV are asymptomatic (their bodies fight off the virus and they are left uninfected with permanent immunity) -others develop an early, acute (short term) illness and display a variety of symptoms but recover from the illness -a third group develops chronic (long term) hepatitis B and they continue to be infectious and may develop serious liver disease involving cirrhosis or cancer. fortunately, antiviral treatments are now available for those with chronic hepatitis B

syphilis ("the great pox")

-a sexually transmitted infection that causes a chancre to appear in the primary stage -present in europe in 1400s and became a pandemic by 1500 -caused by bacterium treponema palladium (spiral shaped and often called a spirochete) -not nearly as common as gonorrhea and chlamydia but its effects are much more serious if left untreated. in most cases, chlamydia and gonorrhea only cause discomfort and sometimes sterility but if SYPHILIS is left untreated, it can damage the nervous system and even cause death -there are many cases today of coinfection (a person is infected with both syphillis and HIV) as syphilis infection makes one more vulnerable to HIV and vice versa

african american AIDS stats

-african americans account for 13% of the population but account for 44% of new infections in the united states

hepatitis b vaccine

-all teenagers and infants are recommended to be vaccinated -men who have sex with men or heterosexual men/women with many partners are urged to get tested

effectiveness of condoms in protecting against HIV infection

-condoms are 80-95% effective in protecting against HIV transmission during heterosexual intercourse if used consistently

HPV vaccine

-almost all cases of cervical cancer are linked to HPV infection (therefore a vaccine against HV would prevent most cases of cervical cancer) -vaccine is called gardasil and must be administered in 3 shots over a 6 month period -goal: administer to girls aged 11-12/before sexually activity starts -vaccine protects against types 16 and 18 (the ones associated with cervical cancer) as well ask two other types that cause most cases of genital warts -randomized controlled trials show the vaccine to be 95% effective -approved for women up to the age of 26 -vaccine also approved for boys in whom it prevents penile, anal, and mouth cancer from HPV

infected women in united states (exposures)

-among women, the leading categories of exposure are heterosexual contact (84%) and injection drug use (16%) -worldwide, the majority of cases result from heterosexual transmission

prostatitis

-an infection or inflammation of the prostate gland -the infection is often caused b the bacterium E. coli and it can also be caused by gonorrhea or chlamydia -may be chronic, may have no symptoms, and may result in only lower pack pain -antibiotics are used in treatment

vaginitis

-an irritation or inflammation of the vagina, usually causing a discharge -common among women and is endemic in college populations -two kinds of vaginitis as well as prostatitis are considered (none of the infections are STIs because they aren't transmitted by sexual contact. they are common infections of the sex organs though)

what sexual behavior is most likely to spread aids?

-anal intercourse (being the receiving partner puts one most at risk) -hetero or homosexual, the more sexual partners you have, the higher risk of contracting HIV -sexual intercourse is riskier if person is infected with HIV (seropositive), is in a high risk group (gay, injection drug user), or if condoms are not used

protease inhibitors

-attack viral enzyme protease which is necessary for HIV to make copies of itself and multiply -another drug is darunavir which acts on viruses that are resistant to the protease inhibitors

syphilis in rest of body

-bacteria can invade mucous membranes of mouth or anus and chancre may appear on lips, tongue, tonsils, or around the anus -bacteria also can enter through a cut in the skin anywhere on the body (so it is possible, but rare, to get syphilis by touching the chancre of an infected person)

chlamydia trachomatis

-bacterium that is spread by sexual contact and infects genital organs of both males and females

chlamydia

-become one of the major sexually transmitted infections in the united states -approx 1.4 million new cases are reported each year in this country (compared with only 300,000 cases of gonorrhea -adolescent girls have a particularly high rate of infection

stage 0

-begins with initial infection and development of antibodies to the virus over the next 2-8 weeks -stage is confirmed via a positive test for antibodies to HIV-1 or HIV-2 -stage 0 lasts as long as person is feeling well and t cell count stays around 1,000 (normal t cell count is approx 1,000 per uL of blood) -if people in stage 0 haven't been tested, they can be asymptomatic carriers and can infect others

post traumatic growth

-between 60 and 80% of people with HIV infection report positive psychological growth following diagnosis -people who experience post traumatic growth and are optimistic tend to have higher t cell counts, helping them to fight disease progression

acquired immune deficiency syndrome (AIDS)

-by the end of 2012, roughly 1.2 million americans had been diagnosed with AIDS and 660,000 died from it -above statistic only takes into account the "top of the iceberg" and doesnt account for those who are infected with HIV but whose symptoms are not severe enough to be classified as AIDS -experts estimate that 75 million ppl worldwide have been infected with HIV, although the majority of them show no symptoms yet and are unaware that they are infected

long-term consequences of herpes

-can develop complications such as meningitis or narrowing of the urethra due to scarring, leading to difficulties with urination. however, most people w/ herpes are not affected by these consequences -herpes increases risk of becoming infected with HIV (prob because blisters open during an outbreak and can make it easy for HIV to enter the body) -virus can be transferred from mother to infant in childbirth, which in some cases leads to serious illness or death in the baby. risk is highest in women who have recently been infected and are having first outbreak. risk is less in women who have had the disease longer, and is low if the women is not having an outbreak -c-sections are usually performed on women with an outbreak, but vaginal delivery is possible if there is not an outbreak

western blot/immunoblot method

-can provide second confirmation on positive ELISA tests -more expensive and more difficult to perform than ELISA tests so it isn't practical for mass screenings -highly accurate, false positives are rare so it is very useful in confirming or disconfirming a positive test from ELISA -both tests ONLY detect the presence of HIV antibodies and they do not predict whether a person will develop symptoms or if they will progress to the AIDS classification

symptoms of gonorrhea in men

-gonococcus invades urethra and produces urethritis (inflammation of the urethra), white blood cells rush to the area and attempt to destroy the bacteria but bacteria win battle -symptoms appear 2 to 5 days after infection, although they may appear as early as the first day or as late as 2 weeks after infection -initially, a clear/thin mucous discharge seeps out of the meatus (the opening at the tip of the penis) -within a day or so, it becomes thick/creamy and may be white, yellowish, or yellow-green. referred to as purulent (puslike) discharge -the meatus (opening at tip of penis) may become swollen -about half of infected men experience a painful burning sensation when urinating -early symptoms of gonorrhea in men are obvious/painful so men often seek treatment immediately and are cured -if disease is not treated, the urethritis spreads up the urethra and causes inflammations in prostate (prostatitis), seminal vesicles (seminal vesiculitis), urinary bladder (cystitis), and epididymis (epididymitis). pain on urination becomes worse and is felt in whole penins. then these early symptoms may disappear as the disease spreads to the other organs. if the epididymitis is left untreated, it may spread to the testicles and resulting scar tissue may cause sterility

what can the new cases of women with HIV be attributed to?

-heterosexual sex (84%) -injection drug use (16%) -what can help: programs that provide sexual assertiveness training to empower women to tell partner to use a condom and the inclusion of women in clinical trials of drug treatments

congenital syphilis

-if a pregnant woman has syphilis, the fetus may be infected when the bacteria cross the placental barrier -if the baby is infected, it gets congenital (meaning present from birth) syphilis -infection may cause early death of fetus (spontaneous abortion) or severe illness at or shortly after birth -may also lead to late complications that show up only at 10 or 20 years of age -women are most infectious to their baby when they have primary or secondary stage syphilis, but they may transmit the infection to the fetus as long as 8 years after the mother's initial infection -if disease is diagnosed and treated before the fourth month of pregnancy, the fetus will not develop the disease -for this reason, a syphilis test is done as a routine part of the blood analysis in a pregnancy test

gonorrheal infection in women

-invades the cervix -pus is discharged but the amount may be very slight -when pus is present, it is yellow-green and irritating to the vulva but is generally not heavy -cervix is primary site of infection but inflammation may also spread to the urethra, causing burning pain during urination -if infection isn't treated, the bartholin glands may become infected and the infection can also spread to the anus/rectum

how does the blood test detect the presence of antibodies to HIV?

-it uses the ELISA (enzyme-linked immunosorbent assay) technique which is easy/cheap -can be used in 2 important ways: to screen donated blood so that infections because of transfusions rarely occur (all donated blood in the united states is now screened with ELISA) AND to help people determine whether they are infected (HIV positive) but are asymptomatic carriers

drawbacks to ELISA test

-long waiting period (more than a week) before test results are known -oraquick rapid HIV test for blood in 2002 and the oraquick rapid HIV test for oral fluid in 2004 (both must be done by clinic, test involves finger stick and detects antibodies to both HIV-1 and HIV-2. the mouth fluid test detects antibodies to HIV-1. in both cases, results are available in 20-30 minutes) -there is also a home test kit for HIV-1 which involves a finger prink and then the dried blood spots are mailed to a lab for anonymous testing

treatment of trichomoniasis

-metronidazole taken orally -if left untreated, trichomoniasis can lead to pelvic inflammatory disease and problems with birth. it also increases susceptibility to HIV infection

preventing STIs

-monogamous relationships with uninfected person -abstain from sexual activity -latex condom, diaphragm for women, female condom -washing genitals before intercourse (prostitutes do this) -inspect partner's genitals -urinating before and after intercourse helps to keep bacteria out of the urethra

non-genital gonorrhea infection

-mouth and throat: (if fellatio is performed on a guy, gonococcus may invade the throat. cunnilingus is less likely to spread gonorrhea and mouth to mouth kissing rarely does) usually asymptomatic, may cause sore throat -anus and rectum: contracted through anal intercourse. symptoms include discharge from rectum and itching, but many cases are asymptomatic -eyes: rarely occurs in adults when genitals are touched and then bacteria containing pus is transferred to their eyes by touching them. eye infection is much more common in newborn infants as it can be transferred from the mother's cervix to the infants eyes during birth (most states require a type of antibiotic for infants eyes to prevent such infection). if eyes are left untreated, the eyes become swollen and painful within a few days and there is a discharge of pus. blindness was a common result in the pre antibiotic era

treatment for hiv/aids

-no cure for aids but treatments can control the disease -effective antiretroviral drugs: AZT, DDI, D4T -some people experience negative side effects and sometimes the drugs stop being effective after a period of time, so scientists stopped pursuing DDI and D4T -protease inhibitors is another class of effective drugs in treatment of hiv

symptoms of genital herpes (HSV-2)

-small, painful blisters or bumps on genitals -appear within 2-3 weeks of infection -in women, they are usually found on vaginal lips and in men they are usually found on the penis (may also be found around the anus if person had anal sex) -blisters can burst and become painful -fever, painful urination, and headaches can occur -virus always lives in body but may remain dormant for the rest of a person's life -symptoms can reoccur unpredictably and the person can repeatedly undergo 7-14 day periods of sores -HSV-1 infections tend to be less severe -people w/ herpes are most infection when they are having an active outbreak, however people are infections even when they aren't having an outbreak and even if they have never by symptomatic. therefore, there is no completely safe period

chancre

-symptom of syphilis -a painless, ulcer like lesion with a hard, raised edge resembling a crater -appears about 3 weeks (as early as 10 days and as late as 3 months) after intercourse with an infected person -cancre appears at the point where the bacteria entered the body. bacteria typically enter through the mucous membranes of the genitals -in men, chancre often appears on penis or scrotum -in women, chancre appears on cervix and thus the woman doesn't notice it and is unaware that she is infected. in women, chancre can also appear on vaginal walls or externally on the vulva

pelvic inflammatory disease (PID)

-symptoms: pelvic pain and sometimes irregular/painful menstruation -if PID isn't treated, scar tissue may form and block the fallopian tubes which would leave a woman infertile -if tubes are partially blocked so sperm can get up them but eggs cannot move down, then ectopic pregnancy can result, because the fertilized egg is trapped in the tube

stage 1

-t cell count drops but is still over 500 -person may still not have any outward symptoms -immune system silently declining people may develop symptoms that are not immediately life threatening such as: swollen lymph nodes, night sweats, fever, diarrhea, persistent yeast infections in the throat or vagina, shingles, fatigue, or abnormal cells in the cervix -with systems of early detection and treatment in the united states, infected people may have few symptoms. those in nations that are more poor are not as fortunate

what demographic in the united states accounts for half of all new stds?

-teens and young adults (between the ages of 15 and 24)

progression of HIV infection

-the CDC established categorization for broad classes of HIV infection and for the progression of the disease -stages are as follows -->

primary stage syphilis

-the first few weeks of a syphilis infection during which the chancre forms/is present -if left untreated, the chancre goes away by itself within 1 to 5 weeks after it appears and this marks the end of the primary stage -the disease has not gone away just because the chancre healed, it has only gone underground

late stage syphilis

-the fourth and final stage of syphilis, during which the disease does damage to major organs of the body such as the lungs, heart, or brain -in cardiovascular late syphilis, the heart and major blood vessels are attacked. this occurs 10 to 40 years after initial infection -cardiovascular syphilis can lead to death -in neurosyphilis, the brain and spinal cord are attacked, leading to insanity and paralysis, which appear 10 to 20 years after infection. neurosyphilis may be fatal as well

secondary stage syphilis

-the second stage of syphilis, occurring several months after infection, during which the chancre has disappeared and a generalized body rash appears -rash doesn't itch or hurt and varies in appearance -hair loss may occur during secondary stage -symptoms are usually troublesome enough to prompt person to seek medical attention -with appropriate treatment at secondary stage, the disease can still be cured and there will be no permanent effects -even without treatment, secondary stage symptoms go away in a few weeks, leading people to believe that the disease has gone away when it has really entered a more dangerous state

latent stage syphilis

-the third stage of syphilis which may last for years during which symptoms disappear although the person is still infected -after symptoms of secondary stage syphilis have disappeared, the disease is in the latent stage and may last for many years -no symptoms in latent stage but treponema palladium is burrowing into tissues in body, esp. blood vessels, central nervous system (brain and spinal cord), and bones -after the first year or so of latent stage, the disease is no longer infectious except that a pregnant woman can still pass it on to a fetus -about half of the people who enter the latent stage remain in it permanently, living out the rest of their lives without further complications BUT the other half move into the dangerous late stage

symptoms of candida

-thick, white, curd-like vaginal discharge, found on the vaginal lips and the walls of the vagina -discharge can cause extreme itching, to the point where the woman is not interested in having intercourse -if a woman gets candida while pregnant, she can transmit it to her baby during birth. baby gets the yeast in its digestive system, a condition known as thrush. thrush can also result from oral-genital sex

symptoms of chlamydia in men

-thin/usually clear discharge, mild discomfort on urination appearing 7 to 21 days after infection -symptoms similar to gonorrhea symptoms in males but gonorrhea tends to produce more painful urination and a more profuse/puslike discharge -diagnosis made from a urine sample in men (and from a sample of cells in the vagina or a urine sample in women). tests are then used to detect the bacterium

pubic lice

-tiny lice that attach themselves to the base of pubic hairs and cause itching; also called crabs -feed on blood from human host -about the size of a pinhead and resemble a crab under magnification -they lay eggs frequently and live for about 30 days but they die within 24 hours if they are taken off a human host -transmitted by sexual contact but they may also be picked up from sheets, towels, sleeping bags, or toilet seats

treatment of chlamydia

-treated with azithromycin or doxycycline -doesn't respond to penicillin -undiagnosed/untreated cases in men: urethral damage, epididymitis (infection of epididymis), reiter's syndrome, proctitis in men who have had anal intercourse -undiagnosed/untreated cases in women: pelvic inflammatory disease (PID), and possible infertility due to scarring of the fallopian tubes (a baby born to an infected mother may develop pneumonia or an eye infection) -no vaccine developed yet but screening is a good preventative measure in order to prevent spreading of chlamydia -best method of prevention is the consistent use of a condom

treatment of pubic lice

-treated with the drugs Nix and Rid which are available without prescription and both kill lice -eggs can live for up to 6 days on clothing so it is important to boil or dry lean one's clothing, get new clean clothes, or use a spray such as R and C

trichomoniasis symptoms for women

-vaginal discharge that irritates the vulva and has an unpleasant smell

ELISA

-very sensitive in detecting HIV antibodies -has a very low rate of false negatives but does produce a substantial amount of false positives (the test saying HIV antibodies are present when they really are not). because of this, positive ELISA tests should always be double checked with another test (immunoblot method)

***viral vs. bacterial STIs***

-viral: hepatitis a/b/c/d/e, herpes, -bacterial: gonorrhea, syphilis, chlamydia

how to prevent vaginitis

-wash vulva carefully and dry it thoroughly every time you shower or bathe -don't use feminine hygiene sprays -wear cotton underpants; nylon and other synthetics retain moisture and vaginitis producing organisms thrive on moisture -avoid wearing pants that are too tight in the crotch -wipe anus from front to back so that bacteria from anus do not get into vagina -never go from anal intercourse to vaginal intercourse

how has the trend of men/women affected by aids changed?

-women made up 7% of AIDS cases in 1985 and now they make up 23% -AIDS is now the 5th leading cause of death for american women between the ages of 25 and 44 and is the leading cause of death for african american women between the ages of 25 and 34

can oral sex transmit HPV?

-yes -individuals infected this way have an increased risk of oral cancers (of mouth or throat)

process of infection

1. virus particles attach cone shaped core to host cell membrane 2. core disintegrates, releasing RNA. reverse transcriptase produces DNA from viral RNA genome 3. DNA copy of the virus genome enters nucleus 4. DNA copy of virus genome integrates into host chromosome 5. transcription of integrated virus makes viral RNA genome 6. core forms; new virus particles bud from host cell

how is HIV spread? (4 ways)

1. by sexual interourse (penis in vagina or anal) 2. by contaminated blood (risk for those who receive blood transfusion if blood has not been screened) 3. by contaminated hypodermic needles (a risk for those who inject drugs or for health care workers who receive accidental sticks) 4. from an infected woman to her baby during pregnancy/childbirth

infected men in united states (exposures)

1. men who have sex with men (48%) 2. heterosexual contact (18%) 3. injection drug use (25%) 4. multiple sources (7%) 5. other, including recipients of contaminated blood transfusions (1%)