Tick-borne illness

Ehrlichia chaffeensis ehrlichiosis

Ehrlichia chaffeensis ehrlichiosis is a bacterial infection of white blood cells spread by lone star ticks across the Southeast and south-central US.

Continental risk map
Where Ehrlichia chaffeensis ehrlichiosis hits hardest
H3 hexagon heatmap of 11,396 reported cases across 51 states.
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State-by-state cases

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Alaska — no CDC-reported casesAKMaine — 73 casesMEVermont — 118 casesVTNew Hampshire — 60 casesNHWashington — 6 casesWAIdaho — no CDC-reported casesIDMontana — 1 caseMTNorth Dakota — 6 casesNDMinnesota — 66 casesMNWisconsin — 390 casesWIMichigan — 35 casesMINew York — 1,005 casesNYMassachusetts — 47 casesMAOregon — 4 casesORNevada — 3 casesNVWyoming — 2 casesWYSouth Dakota — 5 casesSDIowa — 78 casesIAIllinois — 326 casesILIndiana — 191 casesINOhio — 127 casesOHPennsylvania — 119 casesPANew Jersey — 388 casesNJConnecticut — 25 casesCTCalifornia — no CDC-reported casesCAUtah — no CDC-reported casesUTColorado — no CDC-reported casesCONebraska — 63 casesNEMissouri — 2,253 casesMOKentucky — 331 casesKYWest Virginia — 46 casesWVVirginia — 640 casesVAMaryland — 480 casesMDDelaware — 85 casesDERhode Island — 279 casesRIArizona — 6 casesAZNew Mexico — no CDC-reported casesNMKansas — 335 casesKSArkansas — 1,458 casesARTennessee — 684 casesTNNorth Carolina — 867 casesNCSouth Carolina — no CDC-reported casesSCDistrict of Columbia — 4 casesDCHawaii — no CDC-reported casesHIOklahoma — 282 casesOKLouisiana — 13 casesLAMississippi — 40 casesMSAlabama — 128 casesALGeorgia — 48 casesGATexas — 72 casesTXFlorida — 207 casesFLCASES · PER STATE
none
most cases

11,396 reported cases across 51 states.

Top 8 states
#NameCases
1Missouri2,253
2Arkansas1,458
3New York1,005
4North Carolina867
5Tennessee684
6Virginia640
7Maryland480
8Wisconsin390
JFMAMJJASOND

Cases peak in June — about 1,841 cases reported.

MonthCases
Jan62
Feb56
Mar129
Apr334
May1,081
Jun1,841
Jul1,484
Aug801
Sep534
Oct248
Nov152
Dec78

Year-over-year

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5,8434,3822,9221,461020192022REPORTED CASES · PER YEAR

Ticks that carry it

1 known
TickScientific nameOne-liner
Lone star tickAmblyomma americanumThe lone star tick spreads ehrlichiosis, STARI, and the bite-acquired alpha-gal red-meat allergy across the Southeast and lower Midwest.

Pathogens that cause it

0 known

Pathogen association not yet seeded for Ehrlichia chaffeensis ehrlichiosis.

Wild facts

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