TABLE 3.

Performance of individual and nested primer pairs in the corresponding multiplex nested PCR assay group

Organism	Detection limit (copy no. of nucleic acids)
	Outer primera	Inner primera	Nested PCRb
Group 1
Influenza A virus	1	1	1
Influenza A virus H1	106	106	102
Influenza A virus H3	103	104	10
Influenza A virus H5	106	106	1
Influenza B virus	1	10	1
Group 2
PIV-1	106	106	1
PIV-2	108	106	1
PIV-3	1010	106	1
PIV-4a,b	108	1010	1
Group 3
hRSV A	102	102	1
hRSV B	104	106	10
hRV	1	1	1
hEV	106	108	104
Group 4
HCoV-OC43	106	104	10
SARS-CoV	102	106	1
HCoV-229E	106	102	1
hMPV	102	102	1
Group 5
M. pneumoniae	1	1	1
C. pneumoniae	104	1	1
L. pneumophila	102	1	1
ADV (A to F)	108	1010	1

^aThe detection limits of outer and inner primers were tested in the form of multiplex primer mix.

^bThe PCR products from the first-round PCR are used as a template for the second-round PCR in the nested PCR limit detection test.