This repository copy of "A Review of Human Carcinogens: Part B: Biological Agents" is part of the IARC Monographs series, published by the International Agency for Research on Cancer (IARC) in 2012. The publication represents the views and expert opinions of an IARC Working Group that met in Lyon, France, in February-March 2009. The monograph evaluates the carcinogenic risks associated with biological agents, including viruses, bacteria, and other biological organisms, and provides a critical review of the scientific evidence on their carcinogenicity in humans. The monograph covers various biological agents such as Epstein-Barr Virus, Hepatitis B and C Viruses, Kaposi Sarcoma Herpesvirus, Human Immunodeficiency Virus-1, Human Papillomaviruses, Human T-Cell Lymphotropic Virus Type 1, Opisthorchis Viverrini and Clonorchis Sinensis, Schistosoma Hematobium, and Helicobacter pylori. Each agent is evaluated based on exposure data, studies of cancer in humans and experimental animals, and other relevant data. The monograph also includes general remarks, a summary, and an evaluation of the carcinogenicity of each agent. The IARC Monographs series aims to identify the causes of human cancer and guide cancer prevention efforts. The monograph is a critical review of the available evidence on the carcinogenicity of these biological agents, providing a scientific basis for public health decisions and risk assessments.This repository copy of "A Review of Human Carcinogens: Part B: Biological Agents" is part of the IARC Monographs series, published by the International Agency for Research on Cancer (IARC) in 2012. The publication represents the views and expert opinions of an IARC Working Group that met in Lyon, France, in February-March 2009. The monograph evaluates the carcinogenic risks associated with biological agents, including viruses, bacteria, and other biological organisms, and provides a critical review of the scientific evidence on their carcinogenicity in humans. The monograph covers various biological agents such as Epstein-Barr Virus, Hepatitis B and C Viruses, Kaposi Sarcoma Herpesvirus, Human Immunodeficiency Virus-1, Human Papillomaviruses, Human T-Cell Lymphotropic Virus Type 1, Opisthorchis Viverrini and Clonorchis Sinensis, Schistosoma Hematobium, and Helicobacter pylori. Each agent is evaluated based on exposure data, studies of cancer in humans and experimental animals, and other relevant data. The monograph also includes general remarks, a summary, and an evaluation of the carcinogenicity of each agent. The IARC Monographs series aims to identify the causes of human cancer and guide cancer prevention efforts. The monograph is a critical review of the available evidence on the carcinogenicity of these biological agents, providing a scientific basis for public health decisions and risk assessments.