Final answer:
The single most important way that the individual health care worker can help control the spread of infection is by washing their hands.
Step-by-step explanation:
The single most important way that the individual health care worker can help control the spread of infection is by washing their hands. Microbes, which are tiny organisms, can live on surfaces and objects that we touch, including our hands. If a health care worker comes into contact with these microbes and then touches their face, the microbes can enter their body and make them sick. By washing their hands regularly, the health care worker can remove these microbes and reduce the risk of spreading infection.