1. Viral STDs Protozoal STD Herpes (viral ulcerative STD) Genital Warts
AIDS
Protozoal STD
Trichomoniasis

2. Genital Herpes Causative agent herpes-simplex virus type 1 & 2
Enveloped DNA virus
Latent virus

3. Signs & Symptoms
Genital itching and burning, fever, myalgia and malaise
Numerous fluid filled blisters on genitals
Burst and form lesions
Lesions heal spontaneously
Most patients will have recurrence

4. Enveloped virus fuses with host cell membrane
Genome enters cell and begins replication
Viruses are released by budding and cell lysis
Blisters form when epithelial cells are killed
Rupture to produce painful ulcerations
Releases millions of viral particles

5. Ocular Herpes
Whitlow – herpes of skin
Oral Herpes

6. Latency follows ulceration
Viral DNA hides within
ganglia
Re-infect cells supplied
by infected nerve

7. Neonatal herpes 1 in 3 newborns affected if mother infected at birth
Debilitating and potentially lethal
Requires cesarean delivery

8. Epidemiology 4 billion infected worldwide No animal reservoir
Non-sexual transmission may occur
Transmission most likely occurs during first days illness
Transmission can happen in absence of symptoms

9. Treatment There is no cure for genital herpes
Once infected there is lifelong risk of transmission
Acyclovir and derivatives reduce severity
Condoms may not be effective in prevention!!!

10. Genital Warts (papillomas)
Causative agent: Human papillomaviruses
30 different HPV strains cause warts
Most common STD in US

11. Warts on genitals, vagina and cervix
Slight pain or itching may occur
May form condylomata acuminata
Warts typically not dangerous
HPV linked to 99% of cervical cancers
May also cause anal, penile, vaginal and oral cancers

12. HPV infects approximately 20 million people in the United States
~ 6.2 million new cases each year
Pap smears don’t detect HPV only abnormal cells
DNA test is available that detects all 13 strains linked to cervical cancer

13. Treatment: Not prevented by condoms!!! New vaccine currently available
Gardasil
Treatment:
Removal of warts by freezing, laser or acid
Typically reoccur

14. AIDS Acquired Immunodeficiency Syndrome Causative agent:
Human Immunodeficiency Virus (HIV)
Most US cases causes by HIV-1
Most African cases caused by HIV-2
Enveloped, RNA retrovirus

15. Signs & Symptoms (of HIV disease):
Fever; head and muscle aches; enlarged lymph nodes; rash
Some individuals are asymptomatic for years
AIDS is characterized by the presence of several opportunistic or rare infections and a T cell count of lower than 200/µl

17. RNA reverse transcribed to DNA
HIV infects host cells
RNA reverse transcribed to DNA
DNA integrates as provirus in host chromosome
Virus may leave genome and kill host cell
Releases additional viruses
Immune system becomes impaired

19. Epidemiology
HIV is spread mainly through sexual contact, needles or from mother to newborn
Global pandemic
40 million cases
~1/3 have developed AIDS

20. Prevention: No vaccine available
Interruption of mother to child transmission via chemotherapy
Needle exchange programs
Educational programs targeting at risk populations
Treatment of other STDs to lessen risk

21. Treatment: Designed to block replication and release of virus
Generally with cocktail of medication (HAART)
Include reverse transcriptase inhibitors; protease inhibitors; and nucleotide analogs

22. Trichomoniasis Causative agent Trichomonas vaginalis
Flagellated leaf shaped protozoan with undulating membrane

23. Signs & Symptoms Most women symptomatic Most men are asymptomatic
Itching of vulva and inner thighs
Itching and burning of the vagina
Frothy, odorous yellowish-green vaginal discharge
Most men are asymptomatic
penile discharge, pain on urination, tender testes or prostatitis

24. Pathogenesis No encysted stage so it can’t survive in environment
Reproduces at pH of 5-6
Reddening and swelling of vagina attributed to trauma of moving protozoan
Frothy discharge most likely due to gas production by organism

25. Epidemiology Humans are the only known host Worldwide distribution
170 new cases worldwide annually
7.5 million in US
Most common curable STD in women
Transmission usually sexual contact; fomites; newborns infected in birth canal

26. Treatment Single dose of metronidazole
Both partners should be treated to prevent re-infection
Vinegar douche for pregnant or nursing women