PUBIC LICE

VECTOR BIOLOGY Three types of lice: Head lice: Pediculus humanus capitis (2-3 mm long) Body lice: Pediculus humanus humanus ( mm long) Pubic lice (crabs): Phthirus pubis ( mm long)

CRABS Phthirus pubis The pubic or crab louse An ectoparasite whose only host are humans Ectoparasite is a parasite that lives outside of its host

VECTOR BIOLOGY All three types of lice: Are ectoparasites: lice live on the surface of the host Move by crawling, as opposed to flying Have humans as their only host Have similar life cycles Head LiceBody Lice Pubic Lice

EPIDEMIOLOGY & RISK FACTORS Pubic Lice (“Crabs”): Current worldwide prevalence estimated 2% Spread through sexual contact and is considered an STD Can be spread through fomites: contact with clothing, linens, and towels belonging to an infected person. Pubic lice found on children can be an indicator of sexual abuse.

SIGNS & SYMPTOMS Itiching or pruritus in the groin area is the most common symptom Secondary bacterial infection can occur from scratching the skin Visible lice eggs (nits) or lice crawling or attached to pubic hair or other body hair are signs of pubic lice infestation Pubic lice on the head (eyelashes or eyebrows) of a child may be an indication of sexual exposure or abuse

LICE LIFE CYCLE Lice stages: 1.Egg/nit 2.Nymph (3 molts) 3.Adult Both nymphs and adults take blood meals from the human host.

LIFE CYCLE Pubic Lice have three stages: Egg Nymph Adult Females will lay approximately 30 eggs during their 3–4 week life span. Eggs hatch after about a week and become nymphs They look like smaller versions of the adults. The nymphs undergo three molts Adults are much broader in comparison to head and body lice. Adults are found only on the human host and require human blood to survive.

DISEASE H ead lice: does not spread disease Body lice spreads bacterial disease ! Pubic lice: does not spread disease

EPIDEMIOLOGY & RISK FACTORS (CONTINUED) Pubic Lice (“Crabs”): Current worldwide prevalence estimated 2% Spread through sexual contact and is considered an STD Can be spread through fomites: contact with clothing, linens, and towels belonging to an infected person. Pubic lice found on children can be an indicator of sexual abuse.

PREVENTION AND CONTROL Sexual contact should be avoided with people who are infested Machine wash and dry clothing worn and bedding used by infested person in hot water (at least 130°F) and high heat drying Do not share clothing, bedding and towels with an infested person Fumigation is not necessary to control pubic lice

VULVOVAGINITIS

VAGINITIS Bacterial Vaginosis (BV) Vulvovaginal Candidiasis (VVC) Trichomoniasis 13

VAGINAL ENVIRONMENT The vagina is a dynamic ecosystem that contains approximately 10 9 bacterial colony-forming units. Normal vaginal discharge is clear to white, odorless, and of high viscosity. Normal bacterial flora is dominated by lactobacilli – other potential pathogens present. Lactic acid helps to maintain a normal vaginal pH of 3.8 to 4.2. Acidic environment and other host immune factors inhibits the overgrowth of bacteria. Some lactobacilli also produce H 2 O 2, a potent microbicide.

VAGINITIS Usually characterized by Vaginal discharge Vulvar itching Irritation Odor Common types Bacterial vaginosis (40%–45%) Vulvovaginal candidiasis (20%–25%) Trichomoniasis (15%– 20%)

OTHER CAUSES OF VAGINITIS Normal physiologic variation Allergic reactions Herpes simplex virus Atrophic vaginitis Foreign bodies

PREPARATION AND EVALUATION OF SPECIMEN Collection of specimen Preparation of specimen slide Examination of specimen slide wet mount Whiff test Vaginal pH

18 WET PREP: COMMON CHARACTERISTICS RBCs Squamous epithelial cell PMN RBCs Sperm Artifact Saline: 40X objective Source: Seattle STD/HIV Prevention Training Center at the University of Washington

WET PREP: LACTOBACILLI AND EPITHELIAL CELLS Saline: 40X objective Lactobacilli Artifact NOT a clue cell Source: Seattle STD/HIV Prevention Training Center at the University of Washington

VAGINITIS DIFFERENTIATION NormalBacterial VaginosisCandidiasisTrichomoniasis Symptom presentation Odor, discharge, itch Itch, discomfort, dysuria, thick discharge Itch, discharge, ~70% asymptomatic Vaginal discharge Clear to white Homogenous, adherent, thin, milky white; malodorous “foul fishy” Thick, clumpy, white “cottage cheese” Frothy, gray or yellow- green; malodorous Clinical findings Inflammation and erythema Cervical petechiae “strawberry cervix” Vaginal pH > 4.5Usually < 4.5> 4.5 KOH “whiff” testNegativePositiveNegativeOften positive NaCl wet mountLacto-bacilli Clue cells (> 20%), no/few WBCs Few to many WBCs Motile flagellated protozoa, many WBCs KOH wet mount Pseudohyphae or spores if non-albicans species

BACTERIAL VAGINOSIS (BV)

22 EPIDEMIOLOGY Most common cause of vaginitis Prevalence varies by population 5%–25% among college students 12%–61% among STD patients Widely distributed

EPIDEMIOLOGY BV linked to Premature rupture of membranes Premature delivery and low birth-weight delivery Acquisition of HIV, N. gonorrhoeae, C. trachomatis, and HSV- 2 Development of PID Post-operative infections after gynecological procedures

RISK FACTORS African American Two or more sex partners in previous six months/new sex partner Douching Lack of barrier protection Absence of or decrease in lactobacilli Lack of H 2 O 2 -producing lactobacilli

TRANSMISSION Currently not considered a sexually transmitted disease, but acquisition appears to be related to sexual activity.

MICROBIOLOGY Overgrowth of bacteria species normally present in vagina with anaerobic bacteria BV correlates with a decrease or loss of protective lactobacilli Vaginal acid pH normally maintained by lactobacilli through metabolism of glycogen. Hydrogen peroxide (H 2 O 2 ) is produced by some Lactobacilli,sp. H 2 O 2 helps maintain a low pH, which inhibits bacteria overgrowth. Loss of protective lactobacilli may lead to BV.

CLINICAL PRESENTATION AND SYMPTOMS Many women (50%–60%) are asymptomatic. Signs/symptoms, when present Reported malodorous (fishy smelling) vaginal discharge Reported more commonly after vaginal intercourse and after completion of menses Symptoms may remit spontaneously.

TREATMENT CDC-recommended regimens Metronidazole 500 mg orally twice a day for 7 days or Metronidazole gel 0.75%, one full applicator (5 g) intravaginally, once or twice a day for 5 days or Clindamycin cream 2%, one full applicator (5 g) intravaginally at bedtime for 7 days

PARTNER MANAGEMENT Relapse or recurrence is not affected by treatment of sex partner(s). Routine treatment of sex partners is not recommended.

VAGINITIS VULVOVAGINAL CANDIDIASIS (VVC)

VVC EPIDEMIOLOGY Affects most females during lifetime, with approximately 50% having two or more episodes Most cases caused by C. albicans (85%–90%) Second most common cause of vaginitis Estimated cost: $1 billion annually in the U.S.

TRANSMISSION Candida species are normal flora of skin and vagina and are not considered to be sexually transmitted pathogens.

MICROBIOLOGY Candida species are normal flora of the skin and vagina. VVC is caused by overgrowth of C. albicans and other non-albicans species. Yeast grows as oval budding yeast cells or as a chain of cells (pseudohyphae). Symptomatic clinical infection occurs with excessive growth of yeast. Disruption of normal vaginal ecology or host immunity can predispose to vaginal yeast infections.

34 CLINICAL PRESENTATION AND SYMPTOMS Vulvar pruritis is most common symptom. Thick, white, curdy vaginal discharge ("cottage cheese-like") Erythema, irritation, occasional erythematous "satellite" lesion External dysuria and dyspareunia

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VULVOVAGINAL CANDIDIASIS Source: Health Canada, Sexual Health and STI Section, Clinical Slide Gallery

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DIAGNOSIS History, signs and symptoms Visualization of pseudohyphae (mycelia) and/or budding yeast (conidia) on KOH or saline wet prep pH normal (4.0 to 4.5) If pH > 4.5, consider concurrent BV or trichomoniasis infection Cultures not useful for routine diagnosis

43 UNCOMPLICATED VVC Mild to moderate signs and symptoms Nonrecurrent 75% of women have at least one episode Responds to short course regimen

CDC-RECOMMENDED TREATMENT REGIMENS FOR UNCOMPLICATED VVC Over-the-Counter Intravaginal Agents Butoconazole 2% cream, 5 g intravaginally for 3 days or Clotrimazole 1% cream 5 g intravaginally for 7-14 days or Fluconazole 150 mg oral tablet, 1 tablet in a single dose Note: The creams and suppositories in these regimens are oil-based and may weaken latex condoms and diaphragms. Refer to condom product labeling for further information.

COMPLICATED VVC Recurrent (RVVC) Four or more episodes in one year Severe Edema Excoriation/fissure formation Non-albicans candidiasis Compromised host

46 COMPLICATED VVC TREATMENT Recurrent VVC (RVVC) 7–14 days of topical therapy, or 100 mg, 150 mg, or 200 mg oral dose of fluconozole repeated every 3 days (days 1,4,and 7) Maintenance regimens (see 2010 CDC STD treatment guidelines) Severe VVC 7–14 days of topical therapy, or 150 mg oral dose of fluconozole repeated in 72 hours

PARTNER MANAGEMENT VVC is not usually acquired through sexual intercourse. Treatment of sex partners is not recommended. A minority of male sex partners may have balanitis and may benefit from treatment with topical antifungal agents to relieve symptoms.

PATIENT COUNSELING AND EDUCATION Nature of the disease Normal vs. abnormal vaginal discharge, signs and symptoms of candidiasis, maintain normal vaginal flora Transmission Issues Not sexually transmitted Risk reduction Avoid douching, avoid unnecessary antibiotic use, complete course of treatment

TRICHOMINIASIS

BACKGROUND Trichomoniasis is a sexually transmitted infection (STI) caused by the motile parasitic protozoan Trichomonas vaginalis. It is one of the most common STIs, both in the United States and worldwide. Infection with T Vaginalis increases the risk of HIV transmission in both men and women Trichominiasis is also associated with adverse pregnancy outcomes, infertility, and cervical neoplasmia Humans are the only host of T Vaginalis Infection is predominantly by sexual intercourse

EPIDEMIOLOGY Trichomoniasis is one of the most common STIs in the United States, with a prevalence estimated at 8 million cases annually Multiple studies have found that T vaginalis infection is less prevalent in men than in women. In female adolescents, trichomoniasis is more common than gonorrhea This is particularly disconcerting in that it increases susceptibility to other infections Unlike other STIs, trichomoniasis generally becomes more common with age and lifetime number of sexual partners

ETIOLOGY Risk factors for T vaginalis infection include: New or multiple partners A history of STIs Current STIs Sexual contact with an infected partner Exchanging sex for money or drugs Using injection drugs Not using barrier contraception (eg, because of oral contraceptives)

RISK FACTORS Multiple sexual partners Lower socioeconomic status History of STDs Lack of condom use

SIGNS AND SYMPTOMS When trichomoniasis does cause symptoms, they can range from mild irritation to severe inflammation. Some people with symptoms get them within 5 to 28 days after being infected, but others do not develop symptoms until much later. Women Women with trichomoniasis may notice itching, burning, redness or soreness of the genitals, discomfort with urination, or a thin discharge with an unusual smell that can be clear, white, yellowish, or greenish.

CLINICAL PRESENTATION IN WOMEN Common sites of T vaginalis infection include the vagina, urethra and endocervix Symptoms include vaginal discharge, itching, odor, dysuria (though commonly asymptomatic) Elevated vaginal pH Forthy discharge and strawberry cervix are classical findings on exam

56 “STRAWBERRY CERVIX” DUE TO T. VAGINALIS Source: Claire E. Stevens/Seattle STD/HIV Prevention Training Center at the University of Washington

CLINICAL PRESENTATION IN MEN Non-gonococcal, non-chlamydial urethritis Symptoms include urethral discharge, dysuria (though commonly asymptomatic) T. vaginalis can be isolated form men with chronic prostatitis

PATHOPHYSIOLOGY T Vaginalis is approximately the size of a white blood cell (WBC) It has 4 flagella anteriorly and 1 flagellum posteriorly

LIFE CYCLE OF TRICHOMONAS VAGINALIS. T vaginalis trophozoite resides in female lower genital tract and in male urethra and prostate It replicates by binary fission The parasite does not survive well in the external environment. T vaginalis is transmitted among humans, the only known host, primarily via sexual intercourse

PATHOPHYSIOLOGY In women, T vaginalis is isolated from the vagina, cervix, urethra, bladder, and Bartholin and Skene glands. During infection, the vaginal pH increases, as does the number of polymorphonuclear leukocytes (PMNs). Symptoms of trichomoniasis typically occur after an incubation period of 4-28 days. Infection may persist for long periods in women Some infections may persist for months or even years

PATHOPHYSIOLOGY In men, the organism is found in the anterior urethra, external genitalia, prostate, epididymis, and semen. It resides the urogenital tract as well Infections only persist for up to 10 days in males

RACE DEMOGRAPHICS In the National Longitudinal Study of Adolescent Health Study, significant differences in the prevalence of trichomoniasis among adolescents were noted by race: White, 1.2%; Asian, 1.8%; Latino, 2.1%; Native American, 4.1%; African American, 6.9%

TREATMENT Oral Metronidazole (Flagyl) Treatment of choice Cure rates of %

PROGNOSIS Pregnant women with T vaginalis infection are more likely than uninfected women to deliver preterm or to have other adverse pregnancy outcomes Including low birth weight, premature rupture of membranes, and intrauterine infection. Respiratory or genital infection in the newborn may also occur T vaginalis infection may also increase the vertical transmission of HIV due to a disruption of the vaginal mucosa. Trichomoniasis may also play a role in cervical neoplasia and postoperative infections

PARTNER MANAGEMENT Sex partners should be treated. Patients should be instructed to avoid sex until they and their sex partners are cured (when therapy has been completed and patient and partner(s) are asymptomatic, about 7 days).

PATIENT COUNSELING AND EDUCATION Nature of the disease May be asymptomatic in both men and women, in women may persist for months to years, untreated trichomoniasis might be associated with adverse pregnancy outcomes, douching may worsen vaginal discharge, alcohol consumption is contraindicated with metronidazole Transmission issues Almost always sexually transmitted, fomite transmission rare, might be associated with increased susceptibility to HIV acquisition