In which phase does a pathogen begin to adversely affect the host?

The infection phase is when a pathogen actively begins to adversely affect the host's health. During this phase, the pathogen has established itself within the host, and its presence can lead to the manifestation of symptoms and various pathological changes. The immune response is usually activated at this time, as the body attempts to fight off the infection. This is in contrast to other phases such as the incubation phase, where the pathogen is present but not yet causing noticeable effects, or the latent phase, where the pathogen may not be active. The recovery phase follows the peak of infection, where the host's body starts to heal and regain health, indicating that the pathogen's impact is decreasing rather than increasing. Therefore, it is in the infection phase that the adverse effects of the pathogen on the host become most prominent.