Infection Detection Lab Manual. Background: An infectious disease is any disease caused by germs like viruses, bacteria, and protozoa that can spread from one person to another. Sc... Infection Detection Lab Manual. Background: An infectious disease is any disease caused by germs like viruses, bacteria, and protozoa that can spread from one person to another. Scientists call these germs pathogens. Viruses are unique pathogens because they cannot reproduce on their own – they rely on a host cell. Once a virus infects a host, it can reproduce through two main cycles: the lytic cycle and the lysogenic cycle. In the lytic cycle, the virus takes over the host cell's machinery to create new virus particles, which then burst out, destroying the cell. In the lysogenic cycle, the viral genetic material integrates into the host's genome, “hiding” in the host until it eventually enters the lytic cycle. Viruses spread by infecting new host cells, often through bodily fluids, air, or direct contact. This lab will simulate the spread of an infectious disease caused by a virus. Our simulation will show how one person who is infected with a disease can infect another person, who in turn can infect others. Read more