What recommendation is likely to have the most impact on controlling the spread of the cold during an illness outbreak at school?

Washing hands often and well is a fundamental practice for controlling the spread of viral infections, including colds. Viruses are easily transmitted through direct contact with contaminated surfaces or through touching the face, particularly the eyes, nose, and mouth. When students wash their hands with soap and water, they remove germs that could otherwise cause illness.

Hand hygiene is particularly effective because it not only targets the viruses that may be on hands but also prevents the transfer of pathogens from one person to another. If this practice is consistently reinforced in schools, it helps create an environment where the potential for cold outbreaks is minimized.

The other choices, while helpful, do not provide the same level of direct action for preventing the spread of colds. For instance, providing more tissues is a supportive measure but does not address the issue of germ transmission on hands. Coughing into sleeves reduces the spread of droplets but doesn't eliminate hands as a route of transmission. Limiting student interaction during recess can help but doesn’t address the opportunity for students to spread germs through touching shared surfaces. Overall, the focus on handwashing stands out as the most effective way to control the spread of illness in a school setting.