Volume 11, Number 8—August 2005
Perspective
Epidemiology and Transmission Dynamics of West Nile Virus Disease
Table 2
West Nile virus (WNV)–positive mosquito pools, by species, United States, 2001–2004*
2001 |
2002 |
2003 |
2004 (through 11/30/2004) |
||||
---|---|---|---|---|---|---|---|
Positive pools, n = 612† | Positive pools, n = 3,720† | Positive pools, n = 5,538† | Positive pools, n = 4,755† | ||||
Species |
% of pools |
Species |
% of pools |
Species |
% of pools |
Species |
% of pools |
Culex pipiens | 57.0 | Cx. pipiens | 47.0 | Cx. tarsalis | 31.5 | Cx. quinquefasciatus | 51.4 |
Cx. restuans | 12.4 | Cx. quinquefasciatus | 19.1 | Cx. pipiens | 20.8 | Cx. tarsalis | 20.4 |
Cx. salinarius | 11.4 | Cx. restuans | 9.1 | Cx. quinquefasciatus | 19.1 | Cx. pipiens | 12.7 |
Culiseta melanura | 4.2 | Cx. tarsalis | 7.6 | Cx. restuans | 15.3 | Cx. restuans | 4.4 |
Cx. quinquefasciatus | 2.1 | Cx. salinarius | 3.6 | Cx. salinarius | 4.5 | Cx. erythrothorax | 3.6 |
Ochlerotatus. triseriatus | 2.1 | Aedes albopictus | 2.0 | Ae. vexans | 2.3 | ||
21 other species‡ | 10.6 | 23 other species‡ | 11.5 | 35 other species‡ | 6.4 | 35 other species‡ | 7.5 |
*Data were derived from reports submitted by state health departments to the Centers for Disease Control and Prevention's Arbonet surveillance system. Mosquito specimens were collected, identified, and tested in the respective state surveillance systems. Pools were reported as positive if they contained detectable levels of one of the following: infectious WNV, WNV RNA, WN viral antigen.
†Includes only WNV-positive pools reported as monospecific, i.e., excludes mixed pools (e.g., Cx. pipiens/restuans) or pools identified only to genus (e.g., Culex species).
‡No other species individually comprised ≥2.0% of the WNV-positive pools.