Annual rabies report
Utah Department of Health and Human Services
2024
Background
Rabies is a preventable viral disease that affects the brain and
spinal cord of mammals. It is most often transmitted through the bite of
an infected animal. In the US, wildlife is the main reservoir of rabies.
In Utah, all rabies testing for animals is performed at the Utah Public
Health Laboratory (UPHL). Animals suspected of having rabies, or that
have exposed a human or domestic animal, are prioritized for testing.
Over the past 5 years (2019–2023), an average of 16 animals tested
positive for rabies each year. Most of these animals were bats, which
are the main wildlife reservoir of rabies in Utah. Because human rabies
is nearly always fatal once symptoms appear, it is critical to report
all possible rabies exposures to public health to ensure life-saving
treatment is provided when necessary. No human cases of rabies have been
reported in the state since 2018; however, an average of 1–2 cases are
reported in the US every year.
Introduction
In 2024, 484 animals were submitted for rabies testing. Of those
submissions, 31 were positive, 404 were negative, and 49 could not be
tested because of poor specimen quality. All 31 rabid animals were bats.
This is the highest known number of positive rabies detections reported
in a single year. A total of 228 bats were tested for rabies virus,
resulting in a 13.6% test positivity rate.
These 31 rabid bats resulted in 13 people and 13 pets being exposed
to rabies. Positive bats were identified across the state in Cache (2),
Davis (3), Grand (3), Iron (1), Kane (2), Salt Lake (6), Sanpete (2),
Wasatch (1), Washington (5), Wayne (1), and Weber (5) counties.
Weekly rabies activity
Most rabid animals in Utah are detected during the months of
June–October. In 2024, the first and last rabid animal detections were a
little earlier than average, on May 17 and October 4, respectively.
Figure 1 shows the number of rabid animals detected each week in 2024
compared to the average number of detections for that week over the past
5 years (2019–2023).
Figure 1. Epidemiological curve, 2024 vs. 5 year average
Summary of rabies testing by local health jurisdiction
In Utah, there are 13 local health jurisdictions. In 2024, specimens
were submitted from every health jurisdiction. Table 1 shows the total
number of specimens tested from each health jurisdiction and a breakdown
of results. Salt Lake County submitted the most specimens for testing.
Figure 2 shows where the positive animals were found. Southwest Utah had
the largest number of rabid animals detected (8). No rabid animals were
detected in San Juan, Summit County, Tooele County, TriCounty, or in
Utah County, despite submitting specimens for testing.
Table 1. Positive, negative, and unsatisfactory results by local
health jurisdiction, 2024
Jurisdiction
Positive
Negative
Unsatisfactory
Total
Bear River (Cache, Rich, and Box Elder counties)
2
23
5
30
Central Utah (Juab, Millard, Piute, Sanpete, Sevier, and Wayne counties)
3
5
1
9
Davis County
3
35
2
40
Salt Lake County
6
172
9
187
San Juan
0
1
1
2
Southeast Utah (Carbon, Emery, and Grand counties)
3
6
2
11
Southwest Utah (Beaver, Garfield, Iron, Kane, and Washington counties)
8
35
12
55
Summit County
0
10
4
14
Tooele County
0
2
0
2
TriCounty (Daggett, Duchesne, and Uintah counties)
0
4
2
6
Utah County
0
59
6
65
Wasatch County
1
7
0
8
Weber-Morgan (Weber and Morgan counties)
5
40
5
50
Unknown
0
5
0
5
Total
31
404
49
484
Figure 2. Map of rabid animal detections by local health
jurisdiction, 2024
Species of animals tested at UPHL
All specimens that tested positive for rabies in 2024 were bats. A
breakdown by species is shown below in Table 2. Note that
Myotis bats were not identified past the genus level. As such,
there were more Myotis bats tested than any other species.
Mexican Free-tailed bats made up the largest share of rabid bats.
Table 2. Rabid bats by species, 2024
Bat species
Positive
Total tested
Percent positivity
Big Brown
7
33
21.2%
Big Free-tailed
0
2
0.0%
Hoary
1
1
100.0%
Mexican Free-tailed
10
59
16.9%
Myotis
5
67
7.5%
Pallid
1
7
14.3%
Silver-haired
1
23
4.3%
Townsend’s Big Ear
0
1
0.0%
Western Pipistrelle
6
11
54.5%
Western Red Bat
0
6
0.0%
Unknown
0
18
0.0%
Any animal that exposes a person or pet or is suspected of having
rabies is tested for rabies at UPHL. Table 3 provides a list of all
species submitted for testing in 2024. Nearly half (47.1%) of all
animals submitted were bats. Cats and dogs combined also made up a large
proportion of animals submitted (41.5%).
Table 3. Species of all animals submitted for testing, 2024
Animal type
Total tested
Percent
Badger
1
0.2%
Bat
228
47.1%
Bear
1
0.2%
Cat
78
16.1%
Dog
123
25.4%
Ferret
1
0.2%
Fox
1
0.2%
Gopher
1
0.2%
Mink
2
0.4%
Mouse
1
0.2%
Raccoon
38
7.9%
Skunk
5
1.0%
Squirrel
4
0.8%
Historical trends in positive rabies detections
Figure 3 shows the number and percentage of bats that tested positive
and the total number tested each year during 2014–2024. The number of
bats testing positive for rabies in a single year over the previous 10
years has ranged from 12–23. As the number of bats submitted for testing
has steadily increased, the percentage of bats testing positive has
decreased. 2024 was notable for the largest number of bats ever
submitted for testing (228), resulting in the largest number of rabid
bat detections (31).
Figure 3. Percent positivity among bats, 2014–2024
Currently, the bat rabies virus variant is the only rabies virus
variant known to be in Utah. Occasionally, terrestrial mammals test
positive for rabies in Utah. In recent years, there have been four wild
animals (3 foxes and 1 skunk) that tested positive. These animals were
likely bitten by a rabid bat, as additional testing revealed they were
infected with a bat virus variant, which aligns with our current
understanding that bats are the main rabies reservoir in Utah. Table 4
lists all species of animal known to test positive for rabies in Utah
and the year of most recent detection as of December 31, 2024. Animals
not included on this list have no recorded positive detections in the
state.
Table 4. Most recent year of positive rabies detection by species
(as of December 31, 2024)
Species
Year of last positive
Bat
2024
Fox
2021
Skunk
2014
Cat
1995
Dog
1993
