The neuraminidases of MDCK grown human influenza A(H3N2) viruses isolated since 1994 can demonstrate receptor binding

Table 3 NAI Inhibition of agglutination of MDCK cultured H3N2 viruses and NA 148 and 151 sequences

Name	CRBC osel ^a	CRBC zan ^a	TRBC osel	TRBC zan	Amino acid 151 ^b	Mutant percentage	Amino acid 148 ^b	Mutant percentage	Sequence coverage
A/Victoria/4/94	1-10	10-100	>1000	>1000	-	-			-
A/Auckland/5/96	1-10	1-10	>1000	>1000	D		T/I	94%	256
A/Victoria/54/96	10	10	10	10	D/G	40%	T		560
A/Auckland/19/96	1-10	1-10	>1000	>1000	D		T/I	14%	230
A/Victoria/6/97	10	10-100	>1000	>1000	D/G	10%	T		500
A/Victoria/314/98	1-10	1-10	10	10	D		T/I	10%	250
A/Victoria/3/99	10	10-100	>1000	>1000	D/N	37%	T		300
A/Victoria/514/00	10	10-100	10	100	D/N	17%	T/I	12%	388
A/Perth/201/01	ND	ND	>1000	>1000	D/N	14%	T		535
A/Perth/200/02	10	10	10	10	D/N	6.5%	T/I	88%	1283
A/Christchurch/28/03	10	10	10	10-100	D/G	10%	T/K	24%	784
A/Wellington/1/04	10	10	10	10	D		I	100%	1005
A/Brisbane/3/05	10	10-100	10	10-100	D/N/G	27%/10%	T		630
A/Victoria/503/06	10	10-100	10	10-100	D/N/G	16%/11%	T		870
A/Brisbane/10/07	10	10	10	10	D/G	39%	T		1193
A/Brisbane/2/08	1-10	10-100	10	10-100	D/N	34%	T		1058

^aFour HA units of virus were preincubated with log₁₀ dilutions of oseltamivir (osel) or zanamivir (zan) for 60 min at 4°C prior to the addition of 1% RBCs. Titers are the minimum NAI concentration required to completely inhibit agglutination of chicken RBCs in the NAI-HI assay. Where consecutive drug dilutions showed partial then full inhibition a range between these two is given.
^bAmino acids at position 151 and 148 based on Ion Torrent PGM deep sequencing.

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