Microbiology
Summary
The human papillomavirus (HPV) is a naked, double-strand DNA virus belonging to the Papillomaviridae family. There are multiple strains of HPV, with each associated with various diseases and conditions. HPV 1 through 4 cause cutaneous warts, often found on the hands and feet, transmitted primarily through physical contact. HPV 6 and 11 lead to laryngeal papillomatosis (recurrent respiratory papillomatosis) and anogenital warts (condyloma acuminata), which are sexually transmitted. The more malignant strains, HPV 16, 18, 31, and 33, are connected with anogenital squamous cell carcinomas.
HPV's capacity to instigate cancer is heightened by its E6 and E7 proteins, which undermine cell cycle regulation by promoting the proteolysis of the tumor suppressor proteins p53 and RB, respectively. Detection of HPV and its associated abnormalities is achieved through a Pap smear, which seeks out koilocytes, squamous epithelial cells that exhibit specific morphological changes due to HPV infection. An essential preventive measure against HPV is the HPV vaccine (Gardasil 9), which provides protection against HPV serotypes 6, 11, 16, and 18, but notably, not against serotypes 1-4.
Lesson Outline
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FAQs
The human papillomavirus (HPV) refers to a group of more than 200 related viruses. Some strains can lead to health issues like warts or papillomas - small, benign, noncancerous lesions - typically on the skin. The term 'papilloma' thus refers to the type of wart caused by some strains of HPV.
Gardasil 9 is a brand of HPV vaccine made to protect against nine different strains of HPV, including ones causing not only anogenital warts but also most forms of cervical cancer. The vaccine stimulates your immune system to produce antibodies that can later disable the viruses which this vaccine is designed to prevent.
HPV comprises more than 200 strains, which are divided into low-risk and high-risk categories. Low-risk HPV strains, such as HPV 6 and 11, typically cause anogenital warts but not cancer. High-risk HPV strains, including HPV 16 and 18, can cause certain types of cancer, such as cervical, oral, and throat cancers. However, infection with a high-risk HPV strain does not necessarily lead to cancer, as the body can often overcome the infection before it causes severe cellular changes.
High-risk strains of HPV are capable of causing the growth of abnormal cells, which may eventually turn into cancer. The most common cancer associated with HPV is cervical cancer, but it can also cause other types of cancer such as vulvar, vaginal, penile, anal, mouth and throat cancers. Despite these risks, it's important to note that most people will resolve HPV infections naturally and not develop cancer.
