Respiratory Syncytial Virus

This test is used to determine whether an infant, an elderly patient, or an immunocompromised patient has respiratory syncytial virus (RSV). It also helps to determine whether or not RSV season has started in your community. This test may be done when it is RSV season (late fall through early spring) and your caregiver wants to determine whether your runny nose, congestion, coughing and/or difficulty breathing are due to RSV or to other causes

RSV testing is used to detect respiratory syncytial virus, a common viral respiratory infection. RSV tends to be seasonal, causing community epidemics in young children, older adults, and immunocompromised patients that begin late in the fall (November or December) and disappear in early spring. In these high-risk groups, RSV can cause pneumonia and bronchiolitis (inflamed bronchioles, the smaller airway passages/branches of the lower respiratory tract, often called croup). Affected patients may have symptoms such as severe coughing, difficulty breathing, and high fevers. 11,000 people a year die from complications of RSV infections, with most deaths occurring in the elderly.

RSV testing detects virus that is being shed in the respiratory/nasal secretions of an infected person. Since detectable amounts of virus are usually only shed for the first few days of an infection, most testing must be done during this time period. There are several methods to test for the virus, but rapid RSV antigen testing is by far the most popular. Rapid RSV antigen tests are frequently performed on-site, in the caregiver's office or the emergency room, with most results available within an hour. In some cases, the sample may be collected and sent to a laboratory for a more sensitive testing method. Results of these RSV tests are usually available the same day.

PREPARATION FOR TEST

Sample collection technique is critical in RSV testing. The best and most frequently used sample is a nasal aspirate or wash. A syringe is used to push a small amount of sterile saline into your nose, then gentle suction is applied (for the aspirate) or the resulting fluid is collected into a cup (for a wash).

NORMAL FINDINGS

You should be negative for this test.

Ranges for normal findings may vary among different laboratories and hospitals. You should always check with your doctor after having lab work or other tests done to discuss the meaning of your test results and whether your values are considered within normal limits.

MEANING OF TEST

Your caregiver will go over the test results with you and discuss the importance and meaning of your results, as well as treatment options and the need for additional tests, if necessary.

If a rapid RSV test is positive, then it is likely that the patient has respiratory syncytial virus. A positive viral culture or genetic viral test can confirm the presence of RSV in the community. A positive RSV cannot, however, tell a caregiver how severe a patient's symptoms are likely to be or how long ago they were infected (symptoms usually appear 4-6 days after infection).

Negative rapid RSV tests may mean that you have something other than RSV or that there is not sufficient virus in the specimen to allow it to be detected. This may be due to either a poor specimen collection or because you are not shedding detectible levels of virus into your respiratory secretions. Adults tend to shed less virus than infants do and those who have had RSV for several days will shed less than those with a more recent infection.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.