Micro 3.4 Papillomaviridae

What is the structure of Papillomaviridae?

Naked, icosahedral capsids

Can Papillomaviridae survive outside the host?

Yes — can survive outside of host for long periods of time

How is Papillomaviridae transmitted?

Direct contact with infected tissue or contaminated fomites

How many species of HPV exist?

Over 100 species

What does HPV manifest as?

Neoplasia known as warts — also called papilloma or verruca

How is neoplasia defined in the context of HPV?

"new tissue"

What does tissue growth require?

Formation of new blood vessels

Is cancer related to HPV neoplasia?

Cancer is a FORM of neoplasia

Do all HPV species infect the same tissue?

No — each species infects different epithelial cell lines

What are two types of warts caused by HPV?

Seed/flat warts

What is the treatment for HPV?

Surgical removal (chemical, lasers, freezing, etc.)

What is the most common STI in the US?

HPV — ~50 million cases reported in 2018

How many HPV strains affect the genital region?

Over 40 species of HPV

How many of those genital HPV strains are oncogenic?

14 of these strains are oncogenic

What strains of HPV cause over 90% of cervical cancers?

Strains 16 and 18

What does a Pap smear detect in HPV testing?

Cervical biopsy looking for the formation of syncytium (giant cells), which form when cells are infected with some viruses — classified as "pre-cancerous cells"

How are genital warts (GW) morphologically different from other warts?

GW differ from seed/plantar warts since they primarily target mucosa rather than stratified squamous

What is the treatment for genital warts?

Surgical removal

What vaccines are available for HPV?

Gardasil and Cervarix

What is the difference between Gardasil and Cervarix?

Gardasil contains 9 antigens and Cervarix contains 2

Who are HPV vaccines approved for?

Men and women up to 40 years old