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Re: H3n2
H3 in Denmark had seven mutations at key antigenic sites
Based on HA amino acid sequence analysis, the Danish A(H3N2) viruses formed two main clades,
A and B (Figure 2).
Clade B is within the defined 3C A(H3) phylogenetic clade, where the 2012/13 A(H3N2)
vaccine component (A/Victoria/361/2011) is assigned,
but the Danish clade A should probably be assigned a new A(H3) clade. Five of the 22
Danish HA sequences included in the phylogenetic analysis, collected from week 46
(11 December 2012) to week 1 (2 January 2013), were from patients who had been
vaccinated before week 47: all five were located in clade A (Figure 2).
Altogether, seven amino acid substitutions in the HA defined the Danish clade A,
compared with egg-grown/tissue grown A/Victoria/361/2011 –
T128A, R/Q156H,V186G;R142G,N145S;N278K;S/Y219S.
Additional substitutions were Q33R, E/D190D and V347M.
The clade B viruses did not possess the substitutions at positions 128, 142 and 347.
The clade A viruses have lost the 126 N-linked glycosylation seen in A/Victoria/361/2011
and clade B (predicted by NetNGlyc 1.0 server [7]. For comparison, we included reference
HA sequences from influenza A(H3) viruses, obtained from the EpiFlu database of the
Global Initiative on Sharing Avian Influenza Data (GISAID) (Table 3).
=================================================0
DK-A = Quebec (Q49R,S61N,T64I,T144A,R158G,N161S,A214S,V239I,N294 K,N328S,V363M)
DK-B = Alberta (Q49R,S61N,T64I,N161S,A214S,V239I,N294K,N328S)
[as compared to Egypt/Iowa/2009]
while the vax-strain A/Victoria/361/2011 seems to have the additional mutations
H172RorQ,G202V,S235SorY,D190EorD
---------------------------------------------------------
6 H3-HAs from USA today at genbank
5 (3CA+2IL) are DK-B=ALB
1 (CA) is DK-A = Quebec
---------------------------------------------------------------
H3 in Denmark had seven mutations at key antigenic sites
Based on HA amino acid sequence analysis, the Danish A(H3N2) viruses formed two main clades,
A and B (Figure 2).
Clade B is within the defined 3C A(H3) phylogenetic clade, where the 2012/13 A(H3N2)
vaccine component (A/Victoria/361/2011) is assigned,
but the Danish clade A should probably be assigned a new A(H3) clade. Five of the 22
Danish HA sequences included in the phylogenetic analysis, collected from week 46
(11 December 2012) to week 1 (2 January 2013), were from patients who had been
vaccinated before week 47: all five were located in clade A (Figure 2).
Altogether, seven amino acid substitutions in the HA defined the Danish clade A,
compared with egg-grown/tissue grown A/Victoria/361/2011 –
T128A, R/Q156H,V186G;R142G,N145S;N278K;S/Y219S.
Additional substitutions were Q33R, E/D190D and V347M.
The clade B viruses did not possess the substitutions at positions 128, 142 and 347.
The clade A viruses have lost the 126 N-linked glycosylation seen in A/Victoria/361/2011
and clade B (predicted by NetNGlyc 1.0 server [7]. For comparison, we included reference
HA sequences from influenza A(H3) viruses, obtained from the EpiFlu database of the
Global Initiative on Sharing Avian Influenza Data (GISAID) (Table 3).
=================================================0
DK-A = Quebec (Q49R,S61N,T64I,T144A,R158G,N161S,A214S,V239I,N294 K,N328S,V363M)
DK-B = Alberta (Q49R,S61N,T64I,N161S,A214S,V239I,N294K,N328S)
[as compared to Egypt/Iowa/2009]
while the vax-strain A/Victoria/361/2011 seems to have the additional mutations
H172RorQ,G202V,S235SorY,D190EorD
---------------------------------------------------------
6 H3-HAs from USA today at genbank
5 (3CA+2IL) are DK-B=ALB
1 (CA) is DK-A = Quebec
---------------------------------------------------------------
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