What virus is known to cause Kaposi sarcoma?

Human Herpesvirus Type 8 (HHV8), also known as Kaposi's Sarcoma-Associated Herpesvirus (KSHV), is the virus specifically known to cause Kaposi sarcoma, a type of cancer that affects the skin and mucous membranes. It typically manifests as purplish lesions and is more commonly seen in individuals with compromised immune systems, such as those infected with HIV.

HHV8 is linked with the development of Kaposi sarcoma primarily due to its ability to induce changes in host cells, leading to uncontrolled cellular proliferation and tumor formation. The association between HHV8 and Kaposi sarcoma is particularly notable in specific populations, such as men who have sex with men and individuals with AIDS, where the incidence of this cancer is significantly elevated.

In contrast, the other viruses listed do not have a direct causative relationship with Kaposi sarcoma. HIV is known for its role in immunosuppression, which increases the risk of infections and cancers, including those triggered by HHV8, but it is not the direct cause of Kaposi sarcoma itself. Hepatitis B Virus and Cytomegalovirus are also associated with other medical conditions but do not directly lead to the development of Kaposi sarcoma