Virology: Papillomaviridae, Parvoviridae, Poxviridae

Human Papillomaviruses: HPVs

Causes human warts

Tissue tropism for cutaneous or mucosal tissue

> 200 genotypes

• 80 are well characterized

• 30 are with sexual transmission and have a role in cancer pathogenesis

Most prevalent sexual transmitted viral disease in the US

• more than 65 million Americans are living with an incurable STD

• Lab diagnosis: histologic assessment of cutaneous biopsy to cytologic examination of cells: DNA probe assays

HPV

Different genotypes with different tissue tropisms

• HPV 1: Plantar warts

• HPV 2 and 4: Common warts on the hand

• HPV 6 and 11: Genital warts

15-20 genotypes cause all cases of cervical cancer

• HPV 16 and 18: more than 60%

• 16 is responsible for oropharynx and penile cancer

Parvovirus

Latin: Small

Single human pathogen: Parvovirus B-19

Causes biphasic diseases

• 5th disease

• Aplastic crisis: shutdown of RBC synthesis

• Hydro’s fetalis: From transplancental inoculation

1st phase: Fever, chills, malaise, myalgia: muscle pain

2nd phase: Rash, arthralgia: Joint Pain

Canine parvo: Type 2

Parvovirus: Canine; Type 2

Highly contagious: Dog to Dog by direct and indirect contact with feces

Vaccine to prevent infection

Mortality: Can reach 91% if untreated

Symptoms

• Extreme lethargy

• Loss of appetite, diarrhea, vomiting, dehydration, anemia, shock, and death

Poxvirus

Largest family of all viruses: Light Microscopy

Smallpox: Played a crucial role for the important of vaccination against diseases

Transmitted by inhaling the virus in droplets or dried crust

Incubation period: 12-14 days; not contagious

Poxvirus: Smallpox

2 ways of infection

• Localized

• Fulminant: System infection with viral spread

1980: WHO declared smallpox had been eradicated

Eliminated: Disease stops circulating in a region

Eradicated: Disease is eliminated worldwide

Poxvirus: Molluscum Contagiosum

Infection occurs

• Nonsexually: Direct contant/fomites

• Sexually

Poxvirus: MonkeyPox

Almost indistinguishable from smallpox except it doesn’t have the small mortality rate or transmissibility