Persistence of Avian Influenza Viruses in Various Artificially Frozen Environmental Water Types

Table 3

Examples of protracted gene and genome conservation in IAVs.

Genes	Late isolate	Subtype	Duration of conservation	Early isolate	Subtype
NS	A/pintail duck; /Akita/714/2006	H5N2	11/34 (11 out of 34 years)	A/duck/Chabarovsk/1610/1972	H3N8 [33]
NA	A/duck/Ontario/16/1977	H2N1	9/27	A/FW/1950 (human)	H1N1 [34]
NA	A/USSR/90/1977 (human)	H1N1	25/27	A/FW/1950 (human)	H1N1 [34]
All except M	A/USSR/90/1977 (human)	H1N1	≤27	A/FW/1950 (human)	H1N1 [35]
M	A/USSR/90/1977 (human)	H1N1	≤30	A/FM/1947 (human)	H1N1 [35]
All	A/Mongolia/111/; 1991 (human)	H1N1	≤57	A/PR/8/1934 (human)	H1N1 [36]
HA	A/Alma Ata/175/; 1983 (human)	H1N1	≤53	A/swine/Iowa/15/1930	H1N1 [37]
HA	A/lake Park ice/ Siberia/2002	H1N1	≤64	A/swine/UK/1938	H1N1 [38]
NP and HA	A/pintail duck; /Ohio/25/1999	H1N1	≤82	A/Brant Goose/; 1/Alaska/1917	H1N? [39]
All	A/duck/Vietnam/568/2005	H5N1	≤8	A/chicken/Hong Kong/220/1997	H5N1 [40]
PB2	A/chicken/Taiwan; /G23/1987	H6N1	15/15	A/duck/Taiwan; /526/1972	H6N1 [13]
HA	A/ChaingMai/4/1985 (human)	H3N2	3/3	A/Philippines/2; /1982 (human)	H3N2 [41]
HA and NP	A/swine/Quebec/; 296/1994	H3N2	≤19	H3N2/Canada/1975 (human)	H3N2 [42]
HA and NP	A/swine/Quebec/; 148/1990	H1N1	≤60	A/swine/Iowa; /15/1930	H1N1 [43]
All	A/Baku/799/1982; (human)	H1N3	≤6	A/whale/Pacific Ocean/19/1976	H1N3 [44]