Influenza (Flu)

  • Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness. The best way to prevent the flu is by getting a flu vaccine each year.

    Flu viruses spread mainly by tiny droplets that are made when people with the flu cough, sneeze, or talk. These droplets can land in the mouths or noses of people who are nearby. Less often, a person might also get flu by touching a surface or object that has flu virus on it and then touching their own mouth, nose, or possibly their eyes. You may be able to pass the flu to others before you know that you are sick, as well as while you are sick. Although people with the flu are most contagious in the first 3-4 days after their illness begins,  some individuals may infect others beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. Some people, especially young children and people with weakened immune systems, might be able to infect others with flu viruses for an even longer time. The time from when a person is exposed to the flu virus to when symptoms begin is about 1 to 4 days, with an average of about 2 days. Complications of the flu can include bacterial pneumonia, ear infections, sinus infections, and worsening of chronic medical conditions.

    Anyone can get the flu (even healthy people), and serious problems related to the flu can happen at any age. Some people are at high risk of developing serious flu-related complications if they get sick. This includes people 65 and older, people with certain chronic medical conditions (such as asthma, diabetes, or heart disease), pregnant women, and young children.

    People who have the flu often feel some or all of these signs and symptoms that usually start suddenly, not gradually:

    • Fever* or feeling feverish/chills
    • Cough
    • Sore throat
    • Runny or stuffy nose
    • Muscle or body aches
    • Headaches
    • Fatigue (very tired)
    • Some people may have vomiting and diarrhea, though this is more common in young children than in adults.

    *It’s important to note that not everyone with flu will have a fever.

     CDC recommendations to help in flu prevention include:

    • Getting a flu vaccination each year
    • Staying away from people who are sick
    • Covering your coughs and sneezes
    • Frequent handwashing
    • Staying home from work or school if you are sick

    It is very difficult to distinguish the flu from other viral or bacterial causes of respiratory illnesses on the basis of symptoms alone. There are tests available to diagnose flu. If you suspect that you have the flu, talk with your healthcare provider about testing and treatment.

    Flu shots are available through your healthcare provider, area clinics, pharmacies, and Collin County Health Department. Free flu shots are available to qualifying children age 6 months to 18 years of age through the Care Van of North Texas and the health department. Additional information can be found at the Centers for Disease Control or at

    Students, staff and parents with flu-like symptoms should stay home until at least 24 hours after they no longer have a fever (without the use of fever-reducing medicine).

    Please notify the attendance office at your school if your child is home with the flu or flu-like symptoms. This will assist the District and Collin County Health Department in monitoring the spread of the flu. AISD is participating in the Collin County Health Department flu surveillance program.