Sexually Transmitted Infections (Stis, Previously Known As Stds)

Sexually Transmitted Infections (STIs, previously known as STDs)

Human Immunodeficiency Virus (HIV) Disease: Acquired Immunodeficiency Syndrome (clinically, AIDS defined as <200 CD4 T cells per mm3)

Two major virus types (several groups and subtypes)– HIV-1 (pandemic), HIV-2 (mostly Africa)

Transmission: direct blood and sexual fluids (transmitted into blood stream), breast milk, congenital (though virus found in very low levels in most bodily fluids)

Target tissue/tropism: (cells containing CD4 and CXCR4) helper T cells, macrophages

Treatment: several antiviral drug families used in combination

Human Papilloma Virus (HPV)- about 40 known strains Disease: warts (benign epithelial growths)

Flat warts, planters warts, seed warts…commonly found on fingers, hands, feet, elbows, and even throat or tongue

Genital warts- 15% population, usually self-limiting clusters of bumps, certain strains can infect cervical epithelia and cause cervical cancer

Transmission: direct contact with wart, fomites (virus must enter tiny cracks in epithelia)

Treatment: removal by freezing, acid, or laser (vaccine for prevention) Detection of cancerous cervical cells by Pap smear (surgical cervix removal)

Herpes Simplex Virus (HSV) Disease: epithelial lesions

HSV2- primarily genital (genital herpes)…

HSV1- primarily orofacial (cold sore, fever blisters, etc.)…

Fatal in infants..HSV1=30% mortality, HSV2=50-80% mortality

Transmission: viral contaminated secretions, oozing lesions

Remain latent in neurons (once you got them, you got them!), when nerve is stimulated the lesions appear

Treatments: acyclovirs, OTC=Abreva, menthol, camphor Other Herpes Virus family members (not necessarily STIs):

Varicella-Zoster Virus (VZV) Diseases: Primary-chicken pox

Recurrent- shingles (zoster)

Transmission: respiratory droplets, fluid from skin pox (respiratory entry)

Cytomegalovirus (CMV) Disease: (usually asymptomatic in adults), immunosuppressed, infants, newborns… enlarged spleen and liver, jaundice, capillary bleeding, ocular damage, mental retardation

Transmission: body fluids and feces

Epstein-Barr Virus (EBV) Disease: most commonly Infectious Mononucleosis

Transmission: virus harbored in lymph nodes and salivary glands…saliva (maybe blood)

Treponema pallidum (spirochete bacterium) Disease: Syphilis

Primary- painless purple ulcers at site of infection, treatable

Secondary- (weeks later) fever, flu-like symptoms, jaundice, hair loss, rash on palms and feet (treatable)

Tertiary- (~1/3 patients, often years later) soft, gummy lesions, vascular damage, nerve damage leading to insanity and personality changes

Treatment: penicillin, other substitutions Neisseria gonorrhoeae (G- diplococcus) Poor survival outside body, easy to kill

Disease: Gonorrhea (“ the Clap”), 50% asymptomatic, ~1 week incubation

Women- reddened cervix, vaginal discharge, painful abdomen and urination, scared Fallopian tubes and sterility

Men- urethral discharge, painful urination, sterility

Transmission: direct sexual contact (any epithelial cell can be infected…rectum, pharynx, etc.)

Treatment: standard antibiotics, silver nitrate added to newborn eyes

Chlamydia trachomatis (very small G- cocci, intracellular bacterium) Disease: Chlamydia (chlamydial urethritis)

75% women and 50% men asymptomatic…gonorrhea-like symptoms but often milder, therefore higher incidence of sterility

Transmission: direct sexual contact (any epithelial cell can be infected…rectum, pharynx, etc.)

Treatment: standard antibiotics

Trichomonas vaginalis (flagellated protozoan) Disease: Trich (vaginitis, urethritis)

(Many women and most men are asymptomatic) Women- vaginitis, watery discharge, painful urination, itching and burning

Men- urethritis, prostatitis

Transmission: sexual contact, occasionally fomites (typically men are reservoirs without symptoms)

Treatment: typically metronidazole