Table.

Series of Influenza Virus Tests.

Testing Material	Influenza virus Laboratory tests	4 days before admission	Hospital day 1	Hospital day 4	Hospital day 22
Nasal swab	Rapid influenza diagnostic test*	A (+), B (-)
Serum	Influenza virus A antibody (CF titers)			8	16
Spinal fluid	Influenza virus A RNA (RT-PCR)		Negative
	Influenza virus B RNA (RT-PCR)		Negative
	Influenza virus A (H1N1) antibody (HI titers)		<10		<10
	Influenza virus A (H3N2) antibody (HI titers)		<10		<10
	Influenza virus A antibody (CF titers)		<1		<1

CF: complement fixation reaction, RT-PCR: reverse transcriptase-polymerase chain reaction, HI: hemagglutination inhibition reaction

Rapid influenza diagnostic test^*was performed by immunochromatography test using enzyme immunoassay for rapid detection of influenza A and B viruses (Espline^® Influenza A&B–N).