Influenza infection
Updated September 11, 2018
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Influenza is a viral infection that commonly peaks in the United States between January and April. Sometimes cases are seen in the surrounding months. Influenza is primarily a respiratory infection causing fever, cough, sore throat, and runny nose. Headaches, body aches, and chills are common. Gastrointestinal symptoms like vomiting and diarrhea are less common but may occur as well.
Most cases of influenza are not serious and will self-resolve over several days. Fever typically lasts 3-5 days. Cold and cough symptoms may last 7-14 days or perhaps even a little longer before they fully resolve.
Rarely, serious complications of influenza such as pneumonia or encephalitis can occur. Patients with underlying risk factors such as cystic fibrosis, moderate or severe asthma, or immunodeficiency are at higher risk for complications of the flu. Occasionally, however, previously healthy people with no identified risk factors can have serious or even life-threatening complications of the flu.
As per guidelines disseminated by the Centers for Disease Control (CDC) and the Massachusetts Department of Public Health (DPH), we make the following recommendations to our patients:
- If your child has symptoms that seem typical of the flu but without signs of serious illness, please do not panic. The CDC guidelines advise that you need not be seen by the doctor. Rest, fever control, and fluids are the mainstays of therapy. If you have any questions about how your child's care should be managed, please feel free to contact our office to request telephone consultation with our phone triage nurse.
- If you think your child may have the flu, s/he should be kept home, so as to minimize contact with other people in the community, until fever has resolved.
- If your child has more severe symptoms (lethargy, respiratory distress, dehydration, or worsening or persistent fevers, for example), please do contact our office. Of course, we will be happy to see your child at any point if you are concerned. If children seem seriously ill, we will help you decide whether referral to the Emergency Department is appropriate.
- Routine testing for influenza is not recommended. In general, it's not important to know whether a patient has the flu or some other "flu-like" illness, because the treatment is generally the same. There are some cases, however, in which it is important to know, as with immunocompromised or very sick patients. We do have "rapid flu" diagnostic tests in our office. These tests provide results within 10 minutes. These tests are not perfect; there can be false positive and false negative tests.
- Antiviral therapy is available for the flu and should be used for severe cases (i.e., children who require hospitalization) and for children with increased risk of complications (for instance, children with immunocompromise). These drugs are only somewhat helpful in routine cases; typically, the duration of illness is shortened by about 1 day. The antiviral drugs can have some unpleasant side effects. Decisions about whether to institute antiviral therapy for children with suspected or confirmed flu infection will have to be made on an individual basis.