Ohio Vectorborne Disease Surveillance Update

The Ohio Department of Health (ODH) Zoonotic Disease Program, in partnership with ODH Laboratory, local public health partners, and sanitary district partners, conducts statewide vectorborne disease surveillance which includes monitoring for human and veterinary cases.

We will monitor for diseases transmitted by mosquitoes and ticks throughout the summer and fall and will report positive results and summary statistics on this website, updated each Friday at noon. Please download the attached document for a more detailed summary of mosquito and tick surveillance in Ohio.

2022 Numbers-At-A-Glance

As of August 4, 2022

2022 Mosquito-borne diseases

West Nile virus

Mosquito surveillance

• 286,356 Culex spp. from 63 agencies in 51 counties pooled into 8,005* samples.
• 136 West Nile virus positive mosquito samples.

* Testing agencies: Ohio Department of Health using RT-PCR assay = 6,220 pools reported, Franklin County Public Health using RAMP assay = 810 pools reported, Columbus Public Health using VecTOR assay = 555 pools reported, Columbus Public Health using RAMP assay = 325 pools reported, Licking County Health Department using RAMP assay = 95 pools reported.

Human surveillance

• 0 West Nile virus cases.
• 0 West Nile virus asymptomatic viremic blood donors.
• 0 West Nile virus asymptomatic viremic organ donors.

Veterinary surveillance

• 0 West Nile virus veterinary cases.

La Crosse/California encephalitis virus

Human surveillance

• 0 La Crosse virus disease cases.
• 0 unspecified California virus cases.

Travel-associated mosquito-borne diseases

Human surveillance

• 0 chikungunya virus cases.
• 2 dengue virus cases: 1 female and 1 male, median age 18 years, traveled to - El Salvador (1) and Guatemala (1).
• 0 Zika virus cases.
• 36 malaria cases: 18 females and 18 males, median age 37 years, traveled to - Cameroon (2), Cote d'Ivoire (2), Democratic Republic of the Congo (2), Ghana (2), Guinea (2), Liberia (1), Nigeria (2), Senegal (1), Sierra Leone (13), Tanzania (1), Uganda (4), and unknown countries (4).

* Ohioans traveling to areas where local transmission is occurring should be aware of the ongoing situation and make every effort to avoid mosquito bites. Additional information can be found from the Centers for Disease Control and Prevention (CDC)'s Travelers' Health and Pan-American Health Organization websites.

2022 Tickborne diseases

Lyme disease, anaplasmosis, babesiosis

Tick surveillance

• 441 blacklegged ticks, Ixodes scapularis, identified from 43 counties - Allen (1), Ashland (1), Ashtabula (13), Athens (19), Belmont (2), Carroll (5), Clermont (3), Columbiana (111), Coshocton (106), Cuyahoga (9), Erie (4), Franklin (6), Gallia (64), Geauga (5), Greene (1), Guernsey (1), Hamilton (5), Highland (2), Hocking (3), Holmes (4), Jackson (2), Jefferson (3), Knox (3), Lake (5), Licking (4), Lucas (1), Mahoning (1), Medina (3), Meigs (2), Montgomery (1), Morrow (1), Noble (1), Ottawa (1), Portage (7), Richland (1), Ross (12), Scioto (1), Stark (3), Summit (11), Tuscarawas (1), Washington (1), Wayne (9), and Williams (2).

Human surveillance

• 168 Lyme disease cases: 57 females and 111 males, median age 15 years, from 39 counties - Athens (1), Belmont (19), Butler (2), Carroll (2), Clermont (8), Columbiana (9), Coshocton (8), Cuyahoga (10), Delaware (3), Fairfield (8), Franklin (12), Gallia (2), Geauga (2), Guernsey (4), Hamilton (4), Hancock (1), Harrison (2), Highland (1), Holmes (5), Jackson (5), Jefferson (6), Knox (3), Lake (1), Licking (3), Mahoning (3), Marion (1), Medina (2), Monroe (1), Morrow (1), Muskingum (6), Noble (2), Richland (1), Ross (4), Scioto (1), Stark (6), Summit (4), Trumbull (7), Tuscarawas (6), and Warren (2).
• 4 anaplasmosis cases: 2 females and 2 males, median age 65 years, from 2 counties - Jackson (2) and Warren (2).
• 3 babesiosis cases: 1 female and 2 males, median age 56 years, from 3 counties - Hamilton (1), Montgomery (1), and Stark (1).

Rocky Mountain spotted fever

Tick surveillance

• 1,005 American dog ticks, Dermacentor variabilis, identified.

Human surveillance

• 14 Rocky Mountain spotted fever cases: 9 females and 5 males, median age 44 years, from 10 counties - Butler (1), Clermont (1), Gallia (2), Jackson (3), Lucas (1), Montgomery (1), Pike (2), Ross (1), Stark (1), and Warren (1).

Ehrlichiosis

Tick surveillance

• 249 Lone star ticks, Amblyomma americanum, identified.

Human surveillance

• 5 ehrlichiosis cases: 1 female and 4 males, median age 67 years from 5 counties - Athens (1), Hocking (1), Meigs (1), Ross (1), and Stark (1).

2021 Numbers-At-A-Glance

As of December 7, 2021

2021 Mosquito-borne diseases

West Nile virus

Mosquito surveillance

• 544,582 Culex spp. from 60 agencies in 49 counties pooled into 15,561 samples.
• 1,286 West Nile virus positive mosquito samples.

Human surveillance

• 13 West Nile virus cases: 7 females and 6 males, median age 68 years, from 12 counties - Clark (2), Cuyahoga (1), Fulton (1), Hardin (1), Jefferson (1), Lucas (1), Mahoning (1), Mercer (1), Montgomery (1), Richland (1), Summit (1), and Wood (1).
• 1 West Nile virus asymptomatic viremic blood donor.
• 0 West Nile virus asymptomatic viremic organ donors.

Veterinary surveillance

• 1 West Nile virus equine case.
• Reported by the Ohio Department of Agriculture Animal Disease Diagnostic Laboratory.

La Crosse/Unspecified California encephalitis virus

Human surveillance

• 17 La Crosse virus cases: 5 females and 12 males, median age 6 years, from 12 counties - Franklin (1), Geauga (1), Holmes (1), Knox (4), Marion (1), Morrow (2), Preble (1), Stark (1), Summit (1), Trumbull (1), Tuscarawas (1), and Wayne (2).
• 1 unspecified California virus case: 1 male, aged 9 years.

Travel-associated mosquito-borne diseases

Human surveillance

• 0 chikungunya virus cases.
• 3 dengue cases: 2 females and 1 male, median age 33 years, traveled to - Ecuador (1), India (1), and Mexico (1).
• 0 Zika virus cases.
• 62 malaria cases: 25 females and 37 males, median age 33 years, traveled to - Cameroon (6), Chad (1), Cote d'Ivoire (2), Gambia (1), Ghana (4), Guinea (8), Kenya (4), Liberia (2), Mali (1), Nigeria (4), Senegal (2), Sierra Leone (10), Sudan (2), Togo (1), Uganda (1), and unknown countries (13).

* Ohioans traveling to areas where local transmission is occurring should be aware of the ongoing situation and make every effort to avoid mosquito bites. Additional information can be found from the Centers for Disease Control and Prevention (CDC)'s Travelers' Health and Pan-American Health Organization websites.

2021 Tickborne diseases

Lyme disease, anaplasmosis, babesiosis

Tick surveillance

• 659 blacklegged ticks, Ixodes scapularis, submitted from 50 counties - Ashland (62), Ashtabula (9), Athens (37), Belmont (1), Butler (1), Champaign (1), Clark (2), Clermont (1), Clinton (1), Columbiana (7), Coshocton (214), Cuyahoga (3), Delaware (7), Erie (19), Fairfield (8), Fayette (9), Franklin (7), Gallia (1), Geauga (3), Greene (2), Guernsey (2), Hamilton (3), Highland (8), Hocking (7), Jackson (1), Jefferson (1), Knox (56), Lake (4), Lawrence (1), Licking (30), Lorain (4), Lucas (1), Madison (9), Medina (4), Meigs (2), Mercer (2), Monroe (13), Morrow (8), Muskingum (1), Ottawa (1), Portage (6), Richland (63), Ross (2), Stark (8), Summit (9), Trumbull (5), Tuscarawas (2), Vinton (1), Warren (4), and Wayne (6).

Human surveillance

• 542 Lyme disease cases: 215 females and 327 males, median age 40 years, from 59 counties - Allen (1), Ashland (1), Ashtabula (1), Belmont (42), Carroll (6), Clark (3), Clermont (8), Columbiana (8), Coshocton (19), Cuyahoga (27), Delaware (9), Erie (3), Fairfield (6), Franklin (23), Gallia (2), Geauga (4), Guernsey (3), Hamilton (8), Hardin (1), Harrison (23), Henry (1), Hocking (4), Holmes (10), Jackson (11), Jefferson (32), Knox (23), Lake (3), Lawrence (1), Licking (27), Logan (1), Lorain (1), Lucas (2), Madison (1), Mahoning (10), Mercer (3), Monroe (3), Montgomery (8), Morrow (1), Muskingum (16), Noble (10), Ottawa (2), Paulding (1), Perry (1), Pickaway (1), Pike (2), Portage (15), Richland (9), Ross (6), Sandusky (1), Scioto (1), Seneca (2), Stark (42), Summit (28), Trumbull (16), Tuscarawas (38), Union (1), Warren (3), Wayne (5), and Wood (2).
• 2 anaplasmosis cases: 0 females and 2 males, median age 57 years, from 2 counties - Delaware (1) and Henry (1).
• 3 babesiosis cases: 3 females and 0 males, median age 63 years, from 3 counties - Cuyahoga (1), Medina (1), and Scioto (1).

Rocky Mountain spotted fever

Tick surveillance

• 1,400 American dog ticks, Dermacentor variabilis, submitted.

Human surveillance

• 29 Rocky Mountain spotted fever cases: 9 females and 20 males, median age 50 years, from 14 counties - Athens (1), Cuyahoga (1), Erie (1), Franklin (1), Gallia (2), Hamilton (2), Jackson (13), Knox (1), Meigs (1), Montgomery (2), Pike (1), Vinton (1), Warren (1), and Wayne (1).

Ehrlichiosis

Tick surveillance

• 564 Lone star ticks, Amblyomma americanum, submitted.

Human surveillance

• 8 ehrlichiosis cases: 5 females and 3 males, median age 54 years, from 7 counties - Athens (1), Butler (1), Clermont (1), Franklin (1), Gallia (1), Hamilton (1), and Jackson (2).

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