MMWR Morb Mortal Wkly Rep. 2009 Aug 07;58(30):826-829
Summary: CDC has evaluated 65 clinical respiratory specimens collected during April–May 2009 that had previously tested positive either for novel influenza A (H1N1) or for seasonal influenza A (H1N1) or A (H3N2) viruses by real-time reverse transcription–polymerase chain reaction (rRT-PCR) assay.
The results showed that the overall sensitivity was low (40%–69%) among all specimens tested and declined substantially as virus levels decreased (and Ct values increased). These findings indicate that a negative result does not rule out infection with novel influenza A (H1N1) virus. Patients with illnesses compatible with novel influenza A (H1N1) virus infection but with negative rapid influenza diagnostic tests(RIDT) results should be treated empirically based on the level of clinical suspicion, underlying medical conditions, severity of illness, and risk for complications.
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