What symptom would prevent an employee from working in the restaurant?

Vomiting is a significant symptom that would prevent an employee from working in a restaurant environment. This is primarily due to health and safety regulations that aim to prevent the spread of foodborne illnesses among both employees and customers. When an employee is vomiting, there’s a high risk of contaminating food surfaces or products, potentially leading to illness outbreaks.

In a food service setting, it's crucial that employees are in good health to maintain hygiene standards and protect public health. Symptoms like headache, dry skin, or a runny nose may be uncomfortable but typically do not pose the same immediate risk of contamination as vomiting. Thus, the presence of vomiting necessitates that the employee refrain from work until they are symptom-free to ensure a safe and healthy environment for everyone.