Q. I recently took my 12-year-old daughter to her pediatrician. She was having fever, chills and body aches. I had expected her to get a flu test, but the doctor did not recommend the test because she said it would not be very accurate this early in the flu season. Is this true?
Influenza is a viral illness. Common symptoms include:
* Fever
* Body aches
* Sore throat
* Runny nose
* Cough
Several other viruses can cause "flu-like" illnesses with the same symptoms: RSV, rhinovirus, adenovirus, and parainfluenza virus are examples of some of these. Distinguishing between a case of influenza and a "flu-like" illness can be difficult.
Over the past several years, rapid flu tests have become available for use in doctor's offices. These tests typically require a nasal swab or throat swab and can provide a result in about 15 minutes. Although these rapid tests are convenient, they do not provide the same amount of accuracy as the tests that are used in hospitals.
Some rapid flu tests may have a low sensitivity, meaning they may detect influenza only about 50 percent of the time. In other cases, the rapid flu test may demonstrate frequent false positives - tests that indicate a person has influenza when he or she does not. Because of the way statistics work, rapid flu tests are more accurate during peak influenza season (typically January and February) and less accurate at other times of the year.
The Centers for Disease Control and Prevention has recently established guidelines for the diagnosis of influenza and the use of rapid flu tests by community physicians. Health care providers must take several factors into consideration when deciding whether to use a rapid flu test, including local prevalence of influenza and whether the diagnosis will change the physician's treatment plan.
