State Tested Nursing Assistant (STNA) Practice Exam

Elevated body temperature is considered a sign of infection because it is a common physiological response to the presence of pathogens in the body, such as bacteria or viruses. When the body detects an invasion of these harmful microorganisms, the immune system triggers an increase in temperature as a defense mechanism. This raised temperature, often referred to as a fever, can help inhibit the growth of pathogens and enhance the immune system's response. In contrast, increased appetite, a calm demeanor, and improvement in mobility do not indicate infection. Typically, a person experiencing an infection might have a reduced appetite due to illness, may appear less calm or more fatigued due to the body's stress response, and may have limitations in mobility due to pain or discomfort related to the infection. Thus, while the other options may reflect various aspects of health, only an elevated body temperature is a direct sign of infection.