Table 1.
Relationship between duration week from the lowest WSD week to the peak week and proportions of circulated type/subtype of influenza virus
|
Seasons |
Lowest WSD week (a) |
Peak week* (b) |
Duration between (a) and (b), weeks |
Prevalence of type or subtype of influenza virus in early phase of the season† |
|||||
|---|---|---|---|---|---|---|---|---|---|
| A/H3N2 | A/H1N1 | B | |||||||
| 1999/2000 |
51st, 1999 |
5th, 2000 |
6 |
45.2% |
A/Sydney/5/97 |
54.8% |
A/New Caledonia/20/99 |
0.0% |
- |
| 2000/2001 |
48th, 2000 |
10th, 2001 |
14 |
14.3% |
A/Panama/2007/99 |
43.4% |
A/New Caledonia/20/99 |
42.3% |
B/Sichuan/379/99 |
| 2001/2002 |
1st, 2002 |
8th, 2002 |
7 |
38.3% |
A/Panama/2007/99 |
51.2% |
A/New Caledonia/20/99 |
10.5% |
B/Shandong/7/97 |
| 2002/2003 |
52nd, 2002 |
5th, 2003 |
5 |
85.4% |
A/Fujian/411/2002 |
0.0% |
-‡ |
14.6% |
B/Shandong/7/97 |
| 2003/2004 |
52nd, 2003 |
6th,2004 |
6 |
98.6% |
A/Fujian/411/2002 |
0.1% |
- |
1.3% |
B/Shanghai/361/2002 |
| 2004/2005 |
42nd, 2004 |
9th, 2005 |
20 |
35.4% |
A/California/7/2004 |
3.7% |
A/New Caledonia/20/99 |
60.9% |
B/Shanghai/361/2002 |
| 2005/2006 |
6th, 2006 |
5th,2006 |
-1§ |
83.0% |
A/Wisconsin/67/2005 |
16.1% |
A/New Caledonia/20/99 |
0.9% |
B/Malaysia/2506/2004 |
| 2006/2007 |
49th, 2006 |
11th, 2007 |
14 |
49.0% |
A/Brisbane/10/2007 |
9.2% |
A/New Caledonia/20/99 ∣ A/Solomon Islands/3/2006 |
41.8% |
B/Malaysia/2506/2004 |
| 2007/2008 |
39th, 2007 |
5th, 2008 |
18 |
5.4% |
A/Brisbane/10/2007 |
93.0% |
A/Solomon Islands/3/2006 |
1.6% |
B/Florida/4/2006 |
| 2008/2009 | 44th, 2008 | 5th, 2009 | 13 | 28.1% | A/Brisbane/10/2007 | 61.8% | A/Solomon Islands/3/2006 | 10.1% | Brisbane/60/2008 |
* The peak week of influenza cases.
† See method section about a definition of “early phase”.
‡ Data not available.
§ Minus value of duration between means that peak week came earlier than the lowest WSD week.
∣ After A/New Caledonia/20/99 was circulated, A/Solomon Islands/3/2006 was equivalently circulated in 2006/2007 season.