Table 2.
Sindbis virus infection rates in biweekly samples of vector mosquito species collected in the River Dalälven floodplains, central Sweden, during 2001 until 2003.
| Species or group | Time perioda | 2001 | 2002 | 2003 | All years |
|---|---|---|---|---|---|
| Culex torrentium/pipiens | Early season | 0/130 (0.0)b | 0/44 (0.0) | 0/101 (0.0) | 0/277 (0) |
| Late season | 1/81 (13.6) | 3/247 (11.9) | 0/48 (0.0) | 4/374 (10.9) | |
| Full season | 1/211 (4.9) | 3/291 (10.0) | 0/149 (0) | 4/651 (6.2) | |
| Culiseta morsitans | Early season | 0/12 (0.0) | 0/18 (0.0) | 0/3 (0.0) | 0/35 (0.0) |
| Late season | 0/241 (0.0) | 2/202 (9.8) | 0/91 (0.0) | 2/533 (3.7) | |
| Full season | 0/253 (0.0) | 2/220 (9.0) | 0/94 (0.0) | 2/568 (3.5) | |
| Total enzootic vectors | Early season | 0/142 (0.0) | 0/62 (0.0) | 0/104 (0.0) | 0/312 (0.0) |
| Late season | 1/322 (3.2) | 5/449 (11.1) | 0/139 (0.0) | 6/907 (6.7) | |
| Full season | 1/464 (2.2) | 5/511 (9.7) | 0/243 (0) | 6/1219 (4.9) | |
| Aedes cinereus | Early season | 0/9262 (0.0) | 0/1754 (0.0) | 0/6262 (0.0) | 0/17,278 (0.0) |
| Late season | 0/3407 (0.0) | 7/9966 (0.73) | 4/6369 (0.63) | 11/19,742 (0.57) | |
| Full season | 0/12,669 (0.0) | 7/11,720 (0.62) | 4/12,631 (0.32) | 11/37,020 (0.30) | |
| Aedes rossicus | Early season | 0/4235 (0.0) | 0/2258 (0.0) | 0/480 (0.0) | 0/6973 (0.0) |
| Late season | 0/2765 (0.0) | 3/8164 (0.37) | 0/543 (0.0) | 3/11,472 (0.26) | |
| Full season | 0/7000 (0.0) | 3/10,422 (0.29) | 0/1023 (0.0) | 3/18,445 (0.16) | |
| Total bridge-vectors | Early season | 0/13,497 (0.0) | 0/4012 (0.0) | 0/6742 (0.0) | 0/24,251 (0.0) |
| Late season | 0/6172 (0.0) | 10/18,130 (0.57) | 4/6912 (0.58) | 14/31,214 (0.46) | |
| Full season | 0/19,669 (0.0) | 10/22,142 (0.46) | 4/13,654 (0.29) | 14/55,465 (0.26) |
a Early season is week 19–28, late season is week 29–37, and full season is 19–37.
b Number of virus isolates / number of mosquitoes assayed (Maximum Likelihood Estimate Infection Rate/1000 mosquitoes).