Which practice is NOT effective in preventing the transmission of infectious diseases?

Using shared utensils is not effective in preventing the transmission of infectious diseases. This practice can facilitate the spread of pathogens from one person to another, as germs and bacteria can easily transfer between utensils and food items. In communal settings, sharing eating or drinking utensils poses a risk, especially if one individual is carrying an infectious agent, which can then infect others.

In contrast, frequent handwashing is a fundamental practice that significantly reduces the presence of germs on hands, helping to prevent illness. Getting vaccinated strengthens the body's defenses against specific infectious diseases, thereby reducing the likelihood of disease transmission. Covering the mouth while coughing is an important way to contain respiratory droplets that can carry infectious agents, reducing the risk of spreading illnesses to others in close proximity.