The flu is a common illness that can often be treated at home. A person who has contracted the flu will usually experience a fever that exceeds 100°F, a cough, a sore throat, a runny nose, a headache, muscle aches, chills, nausea, vomiting, diarrhea, and excessive fatigue. However, complications may occur in high-risk individuals. Doctors consider people older than 65 to be at a higher risk for dangerous complications. Additionally, people with medical conditions such as asthma, heart disease, or diabetes may experience complications. People at risk should consult a doctor if they have contracted the flu. Dominik’s 70-year-old grandmother is very healthy, but over the past few days she has been experiencing a stuffy nose, muscle aches, and chills, and is running a fever of 101°F. He is trying to determine if he should make an appointment with her doctor or treat her at home. According to the passage, she should see a doctor because she is over 65 years old .