Table 1. States conducting selected West Nile virus surveillance activities, United States, 2004 and 2012*.
| Surveillance activity | No. responding states (% with activity) |
% Difference from 2004 to 2012 | |
|---|---|---|---|
| 2012 | 2004 | ||
| Human surveillance | |||
| Formal surveillance system | 50 (98) | 49 (100) | −2 |
| Active surveillance component | 49 (29) | 49 (47) | −18 |
| Use official case definition | 50 (88) | 49 (88) | 0 |
| Require reporting of encephalitis of unknown etiology |
50 (48) |
49 (63) |
−15 |
| To encourage reporting and to suggest a high index of suspicion, did you contact | |||
| Neurologists | 48 (50) | 48 (60) | −10 |
| Critical care specialists | 48 (48) | 49 (57) | −9 |
| Infectious disease specialists |
48 (58) |
49 (82) |
−24 |
| Equine surveillance | |||
| Formal surveillance system | 49 (90) | 49 (94) | −4 |
| Active surveillance component |
44 (5) |
46 (24) |
−19 |
| Designated public health veterinarian within the agency? | |||
| Yes |
50 (76) |
49 (82) |
−6 |
| Avian surveillance | |||
| Formal avian death surveillance | 49 (39) | 49 (98) | −59 |
| Active component | 19 (10) | 48 (44) | −34 |
| Sentinel chicken surveillance | 50 (10) | – | NA |
| Adequate access to wildlife expertise within agency |
50 (76) |
49 (92) |
−16 |
| Mosquito surveillance | |||
| Formal surveillance system |
49 (80) |
49 (96) |
−16 |
| Collect information about mosquito surveillance from LHDs in state? (states only) | |||
| Yes | 49 (90) | 49 (94) | −4 |
| By species? |
43 (86) |
45 (80) |
+6 |
| Do most LHDs in your state conduct surveillance for (states only) | |||
| Adult mosquitoes | 44 (34) | 44 (48) | −14 |
| Larval mosquitoes | 44 (18) | 44 (30) | −11 |
| Adequate access to entomologist in agency or by contract | 50 (64) | 49 (71) | −7 |
*–, not asked; NA, not applicable; asked; LHDs, local health departments.