Rapid flu test falls short in detecting H1N1

March 1, 2010

Identifying pandemic H1N1 flu in children may not be as easy as administering rapid influenza tests, according to 2 studies.

Identifying pandemic H1N1 flu in children may not be as easy as administering rapid influenza tests, some of which have been shown to have poor sensitivity for H1N1 flu detection, 2 studies published in the March issue of Pediatrics found.

In an analysis of 1 rapid influenza diagnostic test (RIDT) for H1N1 flu, researchers found a sensitivity of 45%. There was 62% sensitivity with the same test in a second study.

"Although a positive rapid influenza diagnostic test result was highly accurate in predicting infection with influenza type A H1N1 2009 in children, a negative RIDT result did not preclude a child having H1N1," the authors of the first study reported.

In a second study, which enrolled 820 children aged 17 years and younger (median age, 3.4 years), there was a higher sensitivity among patients aged 5 years or younger than in older children (P=.003).