This theoretical course provides an overview of the fundamental concepts of immunology and virology. It examines how viruses infect host cells, how the immune system detects and responds to pathogens, and the biological basis of common infectious diseases. Key topics include the components of the innate and adaptive immune systems, viral classification and replication cycles, and the body's defense mechanisms against bacterial, viral, and parasitic agents. The course also explores current challenges such as emerging viral threats, vaccination strategies, and immune system disorders. Students are expected to work with scientific literature and develop presentation skills in English as part of the learning process.