Data & Statistics

Annual Summaries

Number and incidence of reported cases of babesiosis, by state and year, 2014–2020*

 

2014

2015

2016

2017

2018

2019

2020

State

No.

Rate

No.

Rate

No.

Rate

No.

Rate

No.

Rate

No.

Rate

No.

Rate

Alabama

1

<0.1

2

<0.1

0

0.0

1

<0.1

0

0

0

0

 0

 0

Alaska§

Arizona

0

0

0

0

0

0

Arkansas

0

0.0

1

<0.1

0

0.0

2

<0.1

1

<0.1

0

0

California

3

<0.1

5

<0.1

3

<0.1

4

<0.1

6

<0.1

2

<0.1

1

<0.1

Colorado§

Connecticut

205

5.7

328

9.1

322

9.0

309

8.6

248

6.9

323

9.0

151

4.2

Delaware

1

0.1

1

0.1

2

0.2

4

0.4

3

0.3

3

0.3

4.0

0.4

District of
Columbia

2

0.3

0

0.0

0

0

Florida

9

<0.1

19

<0.1

24

<0.1

2

<0.1

Georgia

0

0

1

<0.1

0

0

Hawaii§

Idaho§

Illinois

1

<0.1

3

<0.1

2

<0.1

0

0.0

1

<0.1

1

<0.1

5

<0.1

Indiana

0

0.0

0

0.0

0

0.0

1

<0.1

1

<0.1

0

0.00

1

<0.1

Iowa

2

0.1

0

0

0 0

1

<0.1

Kansas

0

0

0

0

0

0

Kentucky

0

0.0

0

0.0

0

0.0

0

0

0

0

0

0

Louisiana

0

0.0

1

<0.1

0

0.0

1

<0.1

1

<0.1

0

0

0

<0.1

Maine

42

3.2

55

4.1

82

6.2

118

8.8

101

7.5

138

10.3

66

4.8

Maryland

2

<0.1

4

0.1

6

0.1

5

<0.1

7

0.1

7

0.1

9

<0.1

Massachusetts

535

7.9

444

6.

517

7.6

591

8.6

527

7.6

636

9.2

580

8.3

Michigan

2

<0.1

3

<0.1

2

<0.1

3

<0.1

1

<0.1

1

<0.1

0

0

Minnesota

49

0.9

45

0.8

50

0.9

60

1.1

49

0.9

55

1.0

Mississippi§

Missouri

1

<0.1

0

0.0

0

0

1

<0.1

0

0

Montana

0

0.0

0

0.0

1

0.1

0

0.0

0

0

0

0

0

0

Nebraska

0

0.0

0

0.0

1

0.1

0

0.0

0

0

0

0

0

0

Nevada§

New Hampshire§

42

3.2

53

4.0

13

1.0

78

5.8

37

2.7

63

4.6

28

2.0

New Jersey

159

1.8

281

3.1

174

1.9

193

2.1

247

2.8

236

2.6

237

2.6

New Mexico§

New York

471

2.4

581

2.9

430

2.2

696

3.5

641

3.3

663

3.4

461

2.3

North Carolina§

North Dakota

0

0.0

3

0.4

1

0.1

0

0.0

1

0.1

0

0.0

0

0.0

Ohio

1

<0.1

2

<0.1

1

<0.1

4

<0.1

4

<0.1

1

<0.1

Oklahoma§

Oregon

1

<0.1

2

<0.1

2

<0.1

5

0.1

2

<0.1

2

<0.1

4

0.1

Pennsylvania§

Rhode Island

172

16.3

190

18.0

155

14.7

161

15.2

165

15.6

158

14.9

193

17.6

South Carolina

3

0.1

2

<0.1

2

<0.1

2

<0.1

1

<0.1

0

0

0

0

South Dakota

1

0.1

0

0.0

0

0.0

0

0.0

0

0

0

0

1

<0.1

Tennessee

0

0.0

1

<0.1

1

<0.1

1

<0.1

1

<0.1

1

<0.1

1

<0.1

Texas

1

<0.1

1

<0.1

1

<0.1

0

0.0

2

<0.1

2

<0.1

3

<0.1

Utah

0

0.0

0

0.0

0

0.0

1

<0.1

1

<0.1

0

0

0

0

Vermont

3

0.5

9

1.4

15

2.4

22

3.5

21

3.4

34

5.4

16

2.5

Virginia

0

0.0

5

<0.1

1

<0.1

3

<0.1

Washington

4

0.1

2

<0.1

0

0.0

1

<0.1

0

0

1

<0.1

0

0

West Virginia

0

0.0

0

0.0

0

0.0

1

0.1

1

<0.1

0

<0.1

0

0

Wisconsin

43

0.7

56

1.0

68

1.2

88

1.5

64

1.1

58

1.0

57

1.0

Wyoming

0

0.0

0

0.0

0

0.0

0

0.0

0

0

0

0

1

<0.1

Total¶#

1,742

0.8

2,074

0.9

1,909

0.8

2,358

0.9

2,161

0.77

2,418

0.86

1,827

0.65

* Year as reported by the health department

† Cases were reported by state of residence, which was not necessarily the state of exposure.

‡ Rate per 100,000 population (11)

§ Babesiosis is not a reportable condition by law in these states

¶ The denominators for calculations of total incidence rates included only the populations of states in which babesiosis was a reportable condition during the pertinent year.

# 2020 data may be lower or higher than previous years. COVID-19 likely had an impact on public health activities including case identification, case investigations, as well as possibly impacting transmission rates. This may reflect the impact of isolation and prevention measures, whether people sought health care when they were ill, and other changes in behavior during the COVID-19 pandemic period.