What term indicates that a person shows no signs or symptoms of infections?

The term that best describes a person who shows no signs or symptoms of infections is "asymptomatic." When someone is asymptomatic, it means that they may carry a disease or infection but do not exhibit any of the typical indicators that would suggest an illness. This is particularly important in the context of public health, as asymptomatic individuals can still be capable of transmitting certain infections to others despite not feeling unwell themselves.

The other terms have specific meanings that do not apply here. For instance, "contagious" refers to the ability of a disease to be spread from one person to another, implying that the person may show symptoms or be capable of transmitting the infection to others. "Incubating" describes the period following exposure to an infectious agent during which the individual may not yet show symptoms but could be in the process of developing the disease. "Virulent" pertains to the severity or harmfulness of a disease-causing organism, indicating how likely it is to cause illness rather than the symptoms present in an infected individual.