Utah monthly rabies surveillance report
August 2023
Summary
As of August 31, 2023, 12 positive bats were reported in Utah. The first bat to test positive in 2023 was identified on May 31. Two bats tested positive during the month of June, two bats tested positive during the month of July, and seven additional bats tested positive during the month of August. The first positive bat of the year is most often identified in June in Utah. Positive bats were identified in Davis (2), Grand (2), Kane (1), Salt Lake (5), and Washington (2) counties. During the five-year period during 2018-2022, the average number of positive bats reported between January and August was 8.6, and the average for the month of August was 2.4.
In 2022, 13 bats (10% of bats tested) tested positive for rabies virus. These 13 rabid bats resulted in 14 people and 17 pets with a confirmed rabies exposure. Positive bats were identified in Davis (2), Garfield (1), Kane (1), Salt Lake (3), Utah (2), Washington (2), and Weber (2) Counties. The species of these bats were: Mexican free-tailed (5, 38%), Myotis (3, 23%), Big brown (3, 23%), Pallid (1, 8%), and unknown (1, 8%–this bat was tested in Orange County, CA and species information was not available). Of the 333 animals tested for rabies at the Utah Public Health Laboratory (UPHL) in 2022, there were 127 bats, 85 dogs, 67 cats, 30 raccoons, 4 foxes, 3 skunks, and 17 other species.
Background: Rabies is a preventable viral disease of mammals and is most often transmitted through the bite of a rabid animal. In Utah, all rabies testing for animals is performed at UPHL. Animals submitted to UPHL for laboratory testing are categorized by the county of the submitting facility. Animals believed to pose a risk for rabies transmission are prioritized for testing. Nearly all of these have potentially exposed a human or domestic animal. Rabies is primarily found in bats in Utah. In each of the past 5 years (2018–2022), an average of 14.2 bats tested positive for rabies. One positive fox was identified in 2021, one fox in 2020, one skunk in 2014, and one fox in 2006. All 4 of these terrestrial mammals were infected with a bat variant of rabies virus. Because human rabies is nearly always fatal, it is critical to report all possible rabies exposures to public health to ensure life-saving postexposure prophylaxis is provided when necessary.
Rabid bat counts by county, Utah, 2023
NOTE: Positive bat counts are indicated with a black data point. Data points overlaid on map are randomly generated within the county in which the bat was found and do not indicate exact locations in each individual county where the animals were found.
Rabid animal counts by month, 2023
NOTE: Rabies surveillance occurs year-round. The months that are most likely to have positive samples based on the seasonality of rabies in Utah are presented here.| Health District | May | June | July | August | September | October | YTD Totals |
|---|---|---|---|---|---|---|---|
| Bear River | 0 | 0 | 0 | 0 | – | – | 0 |
| Central | 0 | 0 | 0 | 0 | – | – | 0 |
| Davis | 0 | 1 | 1 | 0 | – | – | 2 |
| Salt Lake | 1 | 0 | 1 | 3 | – | – | 5 |
| San Juan | 0 | 0 | 0 | 0 | – | – | 0 |
| Southeast | 0 | 0 | 0 | 2 | – | – | 2 |
| Southwest | 0 | 1 | 0 | 2 | – | – | 3 |
| Summit | 0 | 0 | 0 | 0 | – | – | 0 |
| Tooele | 0 | 0 | 0 | 0 | – | – | 0 |
| TriCounty | 0 | 0 | 0 | 0 | – | – | 0 |
| Utah County | 0 | 0 | 0 | 0 | – | – | 0 |
| Wasatch | 0 | 0 | 0 | 0 | – | – | 0 |
| Weber Morgan | 0 | 0 | 0 | 0 | – | – | 0 |
| Total | 1 | 2 | 2 | 7 |
|
|
12 |
Rabid bat counts by species, 2023
| Health District | Big brown | Brazilian free-tailed | Hoary | Pallid | Mexican free-tailed | Myotis | Silver haired | Western Pipistrelle | Unknown | YTD Totals |
|---|---|---|---|---|---|---|---|---|---|---|
| Bear River | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Central | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Davis | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 2 |
| Salt Lake | 1 | 0 | 2 | 0 | 1 | 1 | 0 | 0 | 0 | 5 |
| San Juan | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Southeast | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 2 |
| Southwest | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 3 |
| Summit | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Tooele | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| TriCounty | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Utah County | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Wasatch | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Weber Morgan | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Total | 2 | 0 | 2 | 0 | 1 | 2 | 2 | 2 | 1 | 12 |