| argentina | la pampa province | ostertagia leptospicularis | species | 0 | 1 |
| australia | new south wales | ostertagia ostertagi | species | 0 | 5 |
| australia | queensland | ostertagia ostertagi | species | 0 | 4 |
| australia | tasmania | ostertagia ostertagi | species | 0 | 2 |
| australia | victoria | ostertagia ostertagi | species | 0 | 2 |
| australia | western australia | ostertagia ostertagi | species | 0 | 2 |
| austria | lower austria | ostertagia ostertagi | species | 0 | 1 |
| austria | salzburg | ostertagia leptospicularis | species | 0 | 1 |
| austria | styria | ostertagia ostertagi | species | 0 | 1 |
| belgium | | ostertagia ostertagi | species | 14 | 0 |
| belgium | bruxelles-capitale | ostertagia ostertagi | species | 0 | 1 |
| belgium | flemish region | ostertagia ostertagi | species | 0 | 5 |
| brazil | santa catarina | ostertagia ostertagi | species | 0 | 1 |
| brazil | sao paulo | ostertagia ostertagi | species | 0 | 1 |
| canada | alberta | ostertagia ostertagi | species | 0 | 1 |
| canada | northwest territories | ostertagia gruehneri | species | 0 | 1 |
| canada | nova scotia | ostertagia ostertagi | species | 0 | 1 |
| canada | ontario | ostertagia ostertagi | species | 0 | 3 |
| canada | prince edward island | ostertagia ostertagi | species | 0 | 2 |
| canada | quebec | ostertagia ostertagi | species | 0 | 1 |
| canada | saskatchewan | ostertagia ostertagi | species | 0 | 1 |
| china | | ostertagia sp. nmg-2010 | species | 1 | 0 |
| china | inner mongolia | ostertagia dahurica | species | 5 | 0 |
| china | qinghai | ostertagia dahurica | species | 24 | 0 |
| china | qinghai | ostertagia occidentalis | species | 3 | 0 |
| china | qinghai | ostertagia wuhingensis | species | 1 | 0 |
| china | qinghai | ostertagia xizangensis | species | 26 | 0 |
| china | tibet | ostertagia nianqingtanggulansis | species | 1 | 0 |
| france | | ostertagia leptospicularis | species | 2 | 0 |
| france | aquitaine region | ostertagia leptospicularis | species | 2 | 0 |
| france | ile-de-france region | ostertagia leptospicularis | species | 4 | 0 |
| france | limousin region | ostertagia leptospicularis | species | 2 | 0 |
| france | poitou-charentes region | ostertagia leptospicularis | species | 2 | 0 |
| germany | schleswig-holstein | ostertagia ostertagi | species | 0 | 1 |
| iran | | ostertagia occidentalis | species | 2 | 0 |
| iran | gilan province | ostertagia lyrata | species | 2 | 0 |
| iran | gilan province | ostertagia ostertagi | species | 4 | 0 |
| iran | gilan province | ostertagia trifurcata | species | 4 | 0 |
| iraq | | ostertagia ostertagi | species | 1 | 0 |
| italy | friuli-venezia giulia autonomous region | ostertagia ostertagi | species | 0 | 1 |
| italy | lombardy region | ostertagia leptospicularis | species | 0 | 1 |
| italy | piemonte region | ostertagia lyrata | species | 0 | 1 |
| italy | piemonte region | ostertagia ostertagi | species | 0 | 1 |
| italy | piemonte region | ostertagia trifurcata | species | 0 | 1 |
| italy | south tyrol autonomous region | ostertagia leptospicularis | species | 0 | 1 |
| italy | umbria region | ostertagia arctica | species | 0 | 1 |
| japan | chiba prefecture | ostertagia ostertagi | species | 2 | 0 |
| japan | hokkaido prefecture | ostertagia ostertagi | species | 62 | 1 |
| japan | ishikawa prefecture | ostertagia ostertagi | species | 2 | 0 |
| japan | iwate prefecture | ostertagia ostertagi | species | 7 | 0 |
| japan | okayama prefecture | ostertagia ostertagi | species | 5 | 0 |
| japan | yamaguchi prefecture | ostertagia ostertagi | species | 4 | 0 |
| netherlands | flevoland province | ostertagia ostertagi | species | 0 | 1 |
| netherlands | utrecht province | ostertagia ostertagi | species | 0 | 1 |
| new zealand | | ostertagia leptospicularis | species | 10 | 0 |
| norway | more og romsdal county | ostertagia gruehneri | species | 0 | 2 |
| norway | more og romsdal county | ostertagia occidentalis | species | 0 | 1 |
| norway | more og romsdal county | ostertagia trifurcata | species | 0 | 1 |
| poland | pomorskie province | ostertagia kolchida | species | 0 | 1 |
| poland | pomorskie province | ostertagia leptospicularis | species | 0 | 1 |
| russia | | ostertagia lyrata | species | 1 | 0 |
| russia | | ostertagia ostertagi | species | 1 | 0 |
| russia | moscow oblast | ostertagia antipini | species | 53 | 0 |
| russia | sakha republic | ostertagia gruehneri | species | 2 | 0 |
| russia | tver oblast | ostertagia antipini | species | 1 | 0 |
| saudi arabia | makkah region | ostertagia trifurcata | species | 0 | 1 |
| south africa | eastern cape province | ostertagia ostertagi | species | 0 | 2 |
| spain | andalusia | ostertagia ostertagi | species | 0 | 1 |
| spain | castilla-la mancha | ostertagia leptospicularis | species | 0 | 1 |
| spain | catalonia | ostertagia ostertagi | species | 0 | 1 |
| spain | extremadura | ostertagia leptospicularis | species | 0 | 1 |
| spain | navarra | ostertagia ostertagi | species | 0 | 1 |
| svalbard and jan mayen | | ostertagia arctica | species | 2 | 0 |
| svalbard and jan mayen | | ostertagia gruehneri | species | 3 | 0 |
| svalbard and jan mayen | svalbard | ostertagia arctica | species | 0 | 1 |
| svalbard and jan mayen | svalbard | ostertagia gruehneri | species | 0 | 2 |
| turkey | | ostertagia ostertagi | species | 5 | 0 |
| turkey | afyonkarahisar province | ostertagia ostertagi | species | 0 | 1 |
| united kingdom | england | ostertagia ostertagi | species | 0 | 3 |
| united kingdom | scotland | ostertagia ostertagi | species | 0 | 6 |
| united kingdom | wales | ostertagia ostertagi | species | 0 | 1 |
| united states | | ostertagia ostertagi | species | 15 | 0 |
| united states | california | ostertagia lyrata | species | 0 | 1 |
| united states | california | ostertagia ostertagi | species | 0 | 4 |
| united states | california | ostertagia trifurcata | species | 0 | 1 |
| united states | georgia | ostertagia ostertagi | species | 0 | 1 |
| united states | idaho | ostertagia ostertagi | species | 0 | 1 |
| united states | illinois | ostertagia mossi | species | 0 | 1 |
| united states | louisiana | ostertagia ostertagi | species | 0 | 10 |
| united states | maine | ostertagia lyrata | species | 0 | 1 |
| united states | maine | ostertagia ostertagi | species | 0 | 2 |
| united states | minnesota | ostertagia ostertagi | species | 0 | 1 |
| united states | mississippi | ostertagia ostertagi | species | 0 | 2 |
| united states | montana | ostertagia bisonis | species | 0 | 1 |
| united states | nevada | ostertagia ostertagi | species | 0 | 1 |
| united states | new york | ostertagia ostertagi | species | 0 | 1 |
| united states | ohio | ostertagia ostertagi | species | 0 | 1 |
| united states | oregon | ostertagia occidentalis | species | 0 | 1 |
| united states | texas | ostertagia ostertagi | species | 0 | 3 |
| united states | washington | ostertagia ostertagi | species | 0 | 1 |
| united states | wyoming | ostertagia bisonis | species | 0 | 1 |
| united states | wyoming | ostertagia ostertagi | species | 0 | 1 |
| uzbekistan | | ostertagia gruehneri | species | 1 | 0 |
| uzbekistan | | ostertagia lyrata | species | 1 | 0 |
| uzbekistan | | ostertagia ostertagi | species | 5 | 0 |