Table 1.

Periods of Prevalence for sH3N2 Viruses Used in Current Study

Reference Strain (Abbreviation)	Eras of Prevalencea	Prominent Seasonsb	Vaccine-Use Erasa
A/Aichi/2/1968 (AI/68)	1968–1972	1968–1969; 1969–1970; 1971–1972	1968–1969; 1969–1970; 1970–1971; 1971–1972; 1972–1973
A/Victoria/3/1975(VIC/75)	1975–1977	1975–1976	1976–1977; 1977–1978
A/Bangkok/1/1979(BK/79)	1979–1983	1980–1981; 1982–1983	1980–1981; 1981–1982; 1982–1983;
A/Shanghai/11/1987(SH/87)	1987–1990	1987–1988; 1989–1990	1989–1990
A/Beijing/32/1992(BJ/92)	1992–1996	1992–1993; 1993–1994	1993–1994
A/Wuhan/359/1995(WH/95)	1995–1998	1996–1997	1996–1997; 1997–1998
A/Sydney/5/1997(SY/97)	1997–2000	1997–1998; 1998–1999; 1999–2000	1998–1999; 1999–2000
A/Fujian/411/2002(FJ/02)	2002–2005	2003–2004	2004–2005
A/Brisbane/10/2007(BR/07)	2007–2009	2007–2008	2008–2009; 2009–2010

Abbreviation: sH3N2, human seasonal influenza A(H3N2).

^aData from previous publications [34, 35] and annual US influenza virus surveillance data.

^bProminent influenza seasons were defined as those in which ≥20% of isolates typed and subtyped in that season were the sH3N2 virus [35].