According to the research, the correct option is Period of invasion. The stage of an infectious disease when specific signs and symptoms are seen and the pathogen is at peak activity is the Period of invasion.
<h3>What is an infectious disease?</h3>
It is the disease that is due to the invasion of the body by pathogenic germs, which establish and multiply caused by a local cell injury, secretion of toxins or by the antigen-antibody reaction.
The stage of an infectious disease called the Period of invasion is the time interval between invasion by an infectious agent and the appearance of the first signs and symptoms of the disease.
Therefore, we can conclude that according to the research, the correct option is Period of invasion. The stage of an infectious disease when specific signs and symptoms are seen and the pathogen is at peak activity is the Period of invasion.
Learn more about stages of an infectious disease here: brainly.com/question/14454614
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