aDivision of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
bDivision of Laboratory Diagnosis Management, Korea Centers for Disease Control and Prevention, Cheongju, Korea
cDivision of Bacterial Disease Research, Korea Centers for Disease Control and Prevention, Cheongju, Korea
Copyright ©2019, Korea Centers for Disease Control and Prevention
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Area | Detailed location | N | E |
---|---|---|---|
Yesan | Nojeon-ri, Gwangsi-myeon, Yesan-gun, Chungcheongnam-do | 36° 32′ 2.25″ | 125° 45′ 40.7″ |
Jeonju | Samcheon-dong, Jeonju-si, Jeollabuk-do | 35° 48′ 17.46″ | 127° 08′ 15.81 |
Gurye | Samsan-ri, Ganjeon-myeon, Gurye-gun, Jeollanam-do | 35° 9′ 28.79″ | 127° 32′ 49.40″ |
Hapcheon | Jung-ri, Chogye-myeon, Hapcheon-gun, Gyeongsangnam-do | 35° 33′ 40.75″ | 128° 15′ 15.37″ |
No. of scrub typhus patients | No. of installed traps | No. of collected rodents | Rate of rodent trapping (%) | No. of rodents infested by chigger mites | Proportion of rodents infested by chigger mites (%) | No. of collected chigger mites | Chigger Index | No. of Ot positive rodents | Proportion of Ot positive rodents (%) | No. of Ot positive chigger mite pools | No. of tested chigger mites | Minimum infection rate (%) of chigger mites | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2006 | |||||||||||||
Jan | - | 220 | 25 | 11.4 | 12 | 48.0 | 218 | 8.7 | 1 | 4.0 | - | 50 | - |
Feb | - | 270 | 36 | 13.3 | 26 | 72.2 | 1,275 | 35.4 | - | - | 3 | 582 | 0.5 |
Mar | 1 | 300 | 38 | 12.7 | 33 | 86.8 | 2,148 | 56.5 | 5 | 13.2 | 8 | 1,011 | 0.8 |
Apr | - | 265 | 39 | 14.7 | 27 | 69.2 | 2,929 | 75.1 | 5 | 12.8 | 18 | 1,484 | 1.2 |
May | - | 315 | 42 | 13.3 | 26 | 61.9 | 691 | 16.5 | 1 | 2.4 | 1 | 278 | 0.4 |
Jun | - | 450 | 67 | 14.9 | 11 | 16.4 | 34 | 0.5 | 1 | 1.5 | - | - | - |
Jul | - | 441 | 57 | 12.9 | 1 | 1.8 | 1 | 0.0 | - | - | - | - | - |
Aug | - | 430 | 53 | 12.3 | 10 | 18.9 | 81 | 1.5 | - | - | - | 18 | - |
Sep | 1 | 245 | 23 | 9.4 | 6 | 26.1 | 118 | 5.1 | - | - | - | 29 | - |
Oct | 77 | 490 | 44 | 9.0 | 25 | 56.8 | 1,713 | 38.9 | 1 | 2.3 | 8 | 813 | 1.0 |
Nov | 141 | 485 | 38 | 7.8 | 27 | 71.1 | 1,773 | 46.7 | 3 | 7.9 | 7 | 832 | 0.8 |
Dec | 11 | 395 | 44 | 11.1 | 41 | 93.2 | 1,741 | 39.6 | 4 | 9.1 | 5 | 745 | 0.7 |
Subtotal | 231 | 4,306 | 506 | 11.8 | 245 | 48.4 | 12,722 | 25.1 | 21 | 4.2 | 50 | 5,842 | 0.9 |
2007 | |||||||||||||
Jan | - | 345 | 38 | 11.0 | 28 | 73.7 | 499 | 13.1 | 3 | 7.9 | - | 166 | - |
Feb | - | 360 | 40 | 11.1 | 28 | 70.0 | 2,139 | 53.5 | 4 | 10.0 | 5 | 1,029 | 0.5 |
Mar | - | 465 | 52 | 11.2 | 43 | 82.7 | 2,838 | 54.6 | 2 | 3.8 | 6 | 1,373 | 0.4 |
Apr | - | 435 | 46 | 10.6 | 26 | 56.5 | 1,810 | 39.3 | - | - | 4 | 848 | 0.5 |
May | - | 510 | 45 | 8.8 | 18 | 40.0 | 460 | 10.2 | 2 | 4.4 | 2 | 169 | 1.2 |
Jun | 1 | 485 | 47 | 9.7 | 4 | 8.5 | 22 | 0.5 | 1 | 2.1 | - | 9 | - |
Jul | 1 | 505 | 48 | 9.5 | 1 | 2.1 | 1 | 0.0 | - | - | - | - | - |
Aug | - | 315 | 30 | 9.5 | 9 | 30.0 | 28 | 0.9 | - | - | - | - | - |
Sep | 49 | 335 | 26 | 7.8 | 10 | 38.5 | 150 | 5.8 | 1 | 3.8 | 1 | 47 | 2.1 |
Oct | 136 | 430 | 40 | 9.3 | 38 | 95.0 | 4,517 | 112.9 | 3 | 7.5 | 3 | 2,220 | 0.1 |
Nov | 3 | 435 | 44 | 10.1 | 38 | 86.4 | 5,798 | 131.8 | - | - | 25 | 2,779 | 0.9 |
Dec | 190 | 560 | 66 | 11.8 | 54 | 81.8 | 1,577 | 23.9 | - | - | - | 622 | - |
Subtotal | 421 | 5,180 | 522 | 10.1 | 297 | 56.9 | 19,839 | 38.0 | 16 | 3.1 | 46 | 9,262 | 0.5 |
Total | 9,486 | 1,028 | 10.8 | 542 | 52.7 | 32,561 | 31.7 | 37 | 3.6 | 96 | 15,104 | 0.6 |
C. ika | E. kor | L. ful | L. gem | L. ori | L. pall | L. palp | L. scu | L. sub | L. zet | N. gar | N. jap | N. kwa | N. tam | W. fra | L. spp | Total | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2006 | |||||||||||||||||
Jan | - | 1 | - | - | 102 | - | 45 | - | 1 | 19 | - | - | - | - | - | - | 168 |
Feb | - | 2 | - | - | 168 | 353 | 85 | 1 | 2 | 82 | - | - | - | - | - | - | 693 |
Mar | 1 | 8 | - | 1 | 458 | 579 | 48 | 5 | 2 | 35 | - | - | - | - | - | - | 1,137 |
Apr | - | 2 | - | - | 453 | 949 | 9 | 1 | 2 | 29 | - | - | - | - | - | - | 1,445 |
May | 1 | 3 | - | - | 84 | 303 | 2 | - | 5 | 5 | - | - | - | - | 10 | - | 413 |
Jun | - | - | - | - | 8 | 22 | - | - | 2 | 2 | - | - | - | - | - | - | 34 |
Jul | - | - | - | - | 1 | - | - | - | - | - | - | - | - | - | - | - | 1 |
Aug | - | - | - | - | 29 | 9 | - | - | - | - | 19 | - | - | - | - | 6 | 63 |
Sep | - | - | - | - | 7 | 48 | - | 16 | - | - | 9 | - | - | - | - | 9 | 89 |
Oct | 1 | 71 | - | - | 61 | 253 | 9 | 504 | - | - | - | - | 1 | - | - | - | 900 |
Nov | - | 21 | - | - | 128 | 264 | 147 | 361 | - | 6 | - | 1 | 1 | 12 | - | - | 941 |
Dec | 1 | 23 | - | - | 293 | 215 | 274 | 107 | 4 | 58 | - | - | - | 21 | - | - | 996 |
Subtotal | 4 | 131 | - | 1 | 1,792 | 2,995 | 619 | 995 | 18 | 236 | 28 | 1 | 2 | 33 | 10 | 15 | 6,880 |
2007 | |||||||||||||||||
Jan | - | 6 | - | - | 76 | 74 | 137 | 3 | - | 28 | - | - | - | 9 | - | - | 333 |
Feb | - | 5 | - | - | 219 | 638 | 116 | 16 | 7 | 104 | - | - | - | 5 | - | - | 1,110 |
Mar | 1 | 5 | - | - | 361 | 934 | 87 | 5 | 4 | 60 | - | - | - | 8 | - | - | 1,465 |
Apr | - | 3 | - | - | 332 | 582 | 16 | 1 | 5 | 23 | - | - | - | - | - | - | 962 |
May | 1 | 3 | - | - | 69 | 208 | 1 | - | - | 9 | - | - | - | - | - | - | 291 |
Jun | - | - | - | - | 3 | 10 | - | - | - | - | - | - | - | - | - | - | 13 |
Jul | - | - | - | - | 1 | - | - | - | - | - | - | - | - | - | - | - | 1 |
Aug | 3 | - | 7 | - | 10 | 2 | - | - | 1 | - | 5 | - | - | - | - | - | 28 |
Sep | - | 11 | 1 | - | 33 | 43 | - | 2 | 1 | - | 12 | - | - | - | - | - | 103 |
Oct | 2 | 88 | 8 | - | 124 | 817 | 20 | 1,151 | 1 | 11 | 70 | 1 | - | 2 | 2 | - | 2,297 |
Nov | - | 41 | - | - | 180 | 918 | 613 | 892 | 2 | 116 | 2 | 2 | - | 253 | - | - | 3,019 |
Dec | - | 10 | - | - | 101 | 372 | 243 | 91 | 2 | 50 | - | - | - | 86 | - | - | 955 |
Subtotal | 7 | 172 | 16 | - | 1,509 | 4,598 | 1,233 | 2,161 | 23 | 401 | 89 | 3 | - | 363 | 2 | - | 10,577 |
Total | 11 | 303 | 16 | 1 | 3,301 | 7,593 | 1,852 | 3,156 | 41 | 637 | 117 | 4 | 2 | 396 | 12 | 15 | 17,457 |
% | 0.1 | 1.7 | 0.1 | 0.0 | 18.9 | 43.5 | 10.6 | 18.1 | 0.2 | 3.6 | 0.7 | 0.0 | 0.0 | 2.3 | 0.1 | 0.1 | 100.0 |
C. ika = Cheladonta ikaoensis; E. kor = Euschoengastia koreaensis; L. ful = Leptotrombidium fuller; L. gem = Leptotrombidium gemiticulum; L. ori = Leptotrombidium orientale; L. pall = Leptotrombidium pallidum; L. palp = Leptotrombidium palpale; L. scu = Leptotrombidium scutellare; L. sub = Leptotrombidium subintermedium; L. zet = Leptotrombidium zetum; N. gar = Neotrombicula gardellai; N. jap = Neotrombicula japonica; N. kwa = Neotrombicula kwangneungensis; N. tam = Neotrombicula tamiyai; W. fra = Walchia fragilis; L. spp. = Leptotrombidium species.
Coordinates of the rodent collection sites.
Area | Detailed location | N | E |
---|---|---|---|
Yesan | Nojeon-ri, Gwangsi-myeon, Yesan-gun, Chungcheongnam-do | 36° 32′ 2.25″ | 125° 45′ 40.7″ |
Jeonju | Samcheon-dong, Jeonju-si, Jeollabuk-do | 35° 48′ 17.46″ | 127° 08′ 15.81 |
Gurye | Samsan-ri, Ganjeon-myeon, Gurye-gun, Jeollanam-do | 35° 9′ 28.79″ | 127° 32′ 49.40″ |
Hapcheon | Jung-ri, Chogye-myeon, Hapcheon-gun, Gyeongsangnam-do | 35° 33′ 40.75″ | 128° 15′ 15.37″ |
Summary of collection data and O. tsutsugamushi infections in wild rodents and chigger mites.
No. of scrub typhus patients | No. of installed traps | No. of collected rodents | Rate of rodent trapping (%) | No. of rodents infested by chigger mites | Proportion of rodents infested by chigger mites (%) | No. of collected chigger mites | Chigger Index | No. of Ot positive rodents | Proportion of Ot positive rodents (%) | No. of Ot positive chigger mite pools | No. of tested chigger mites | Minimum infection rate (%) of chigger mites | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2006 | |||||||||||||
Jan | - | 220 | 25 | 11.4 | 12 | 48.0 | 218 | 8.7 | 1 | 4.0 | - | 50 | - |
Feb | - | 270 | 36 | 13.3 | 26 | 72.2 | 1,275 | 35.4 | - | - | 3 | 582 | 0.5 |
Mar | 1 | 300 | 38 | 12.7 | 33 | 86.8 | 2,148 | 56.5 | 5 | 13.2 | 8 | 1,011 | 0.8 |
Apr | - | 265 | 39 | 14.7 | 27 | 69.2 | 2,929 | 75.1 | 5 | 12.8 | 18 | 1,484 | 1.2 |
May | - | 315 | 42 | 13.3 | 26 | 61.9 | 691 | 16.5 | 1 | 2.4 | 1 | 278 | 0.4 |
Jun | - | 450 | 67 | 14.9 | 11 | 16.4 | 34 | 0.5 | 1 | 1.5 | - | - | - |
Jul | - | 441 | 57 | 12.9 | 1 | 1.8 | 1 | 0.0 | - | - | - | - | - |
Aug | - | 430 | 53 | 12.3 | 10 | 18.9 | 81 | 1.5 | - | - | - | 18 | - |
Sep | 1 | 245 | 23 | 9.4 | 6 | 26.1 | 118 | 5.1 | - | - | - | 29 | - |
Oct | 77 | 490 | 44 | 9.0 | 25 | 56.8 | 1,713 | 38.9 | 1 | 2.3 | 8 | 813 | 1.0 |
Nov | 141 | 485 | 38 | 7.8 | 27 | 71.1 | 1,773 | 46.7 | 3 | 7.9 | 7 | 832 | 0.8 |
Dec | 11 | 395 | 44 | 11.1 | 41 | 93.2 | 1,741 | 39.6 | 4 | 9.1 | 5 | 745 | 0.7 |
Subtotal | 231 | 4,306 | 506 | 11.8 | 245 | 48.4 | 12,722 | 25.1 | 21 | 4.2 | 50 | 5,842 | 0.9 |
2007 | |||||||||||||
Jan | - | 345 | 38 | 11.0 | 28 | 73.7 | 499 | 13.1 | 3 | 7.9 | - | 166 | - |
Feb | - | 360 | 40 | 11.1 | 28 | 70.0 | 2,139 | 53.5 | 4 | 10.0 | 5 | 1,029 | 0.5 |
Mar | - | 465 | 52 | 11.2 | 43 | 82.7 | 2,838 | 54.6 | 2 | 3.8 | 6 | 1,373 | 0.4 |
Apr | - | 435 | 46 | 10.6 | 26 | 56.5 | 1,810 | 39.3 | - | - | 4 | 848 | 0.5 |
May | - | 510 | 45 | 8.8 | 18 | 40.0 | 460 | 10.2 | 2 | 4.4 | 2 | 169 | 1.2 |
Jun | 1 | 485 | 47 | 9.7 | 4 | 8.5 | 22 | 0.5 | 1 | 2.1 | - | 9 | - |
Jul | 1 | 505 | 48 | 9.5 | 1 | 2.1 | 1 | 0.0 | - | - | - | - | - |
Aug | - | 315 | 30 | 9.5 | 9 | 30.0 | 28 | 0.9 | - | - | - | - | - |
Sep | 49 | 335 | 26 | 7.8 | 10 | 38.5 | 150 | 5.8 | 1 | 3.8 | 1 | 47 | 2.1 |
Oct | 136 | 430 | 40 | 9.3 | 38 | 95.0 | 4,517 | 112.9 | 3 | 7.5 | 3 | 2,220 | 0.1 |
Nov | 3 | 435 | 44 | 10.1 | 38 | 86.4 | 5,798 | 131.8 | - | - | 25 | 2,779 | 0.9 |
Dec | 190 | 560 | 66 | 11.8 | 54 | 81.8 | 1,577 | 23.9 | - | - | - | 622 | - |
Subtotal | 421 | 5,180 | 522 | 10.1 | 297 | 56.9 | 19,839 | 38.0 | 16 | 3.1 | 46 | 9,262 | 0.5 |
Total | 9,486 | 1,028 | 10.8 | 542 | 52.7 | 32,561 | 31.7 | 37 | 3.6 | 96 | 15,104 | 0.6 |
Ot = Orientia tsutsugamushi.
Species of chigger mites collected from wild rodents.
C. ika | E. kor | L. ful | L. gem | L. ori | L. pall | L. palp | L. scu | L. sub | L. zet | N. gar | N. jap | N. kwa | N. tam | W. fra | L. spp | Total | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2006 | |||||||||||||||||
Jan | - | 1 | - | - | 102 | - | 45 | - | 1 | 19 | - | - | - | - | - | - | 168 |
Feb | - | 2 | - | - | 168 | 353 | 85 | 1 | 2 | 82 | - | - | - | - | - | - | 693 |
Mar | 1 | 8 | - | 1 | 458 | 579 | 48 | 5 | 2 | 35 | - | - | - | - | - | - | 1,137 |
Apr | - | 2 | - | - | 453 | 949 | 9 | 1 | 2 | 29 | - | - | - | - | - | - | 1,445 |
May | 1 | 3 | - | - | 84 | 303 | 2 | - | 5 | 5 | - | - | - | - | 10 | - | 413 |
Jun | - | - | - | - | 8 | 22 | - | - | 2 | 2 | - | - | - | - | - | - | 34 |
Jul | - | - | - | - | 1 | - | - | - | - | - | - | - | - | - | - | - | 1 |
Aug | - | - | - | - | 29 | 9 | - | - | - | - | 19 | - | - | - | - | 6 | 63 |
Sep | - | - | - | - | 7 | 48 | - | 16 | - | - | 9 | - | - | - | - | 9 | 89 |
Oct | 1 | 71 | - | - | 61 | 253 | 9 | 504 | - | - | - | - | 1 | - | - | - | 900 |
Nov | - | 21 | - | - | 128 | 264 | 147 | 361 | - | 6 | - | 1 | 1 | 12 | - | - | 941 |
Dec | 1 | 23 | - | - | 293 | 215 | 274 | 107 | 4 | 58 | - | - | - | 21 | - | - | 996 |
Subtotal | 4 | 131 | - | 1 | 1,792 | 2,995 | 619 | 995 | 18 | 236 | 28 | 1 | 2 | 33 | 10 | 15 | 6,880 |
2007 | |||||||||||||||||
Jan | - | 6 | - | - | 76 | 74 | 137 | 3 | - | 28 | - | - | - | 9 | - | - | 333 |
Feb | - | 5 | - | - | 219 | 638 | 116 | 16 | 7 | 104 | - | - | - | 5 | - | - | 1,110 |
Mar | 1 | 5 | - | - | 361 | 934 | 87 | 5 | 4 | 60 | - | - | - | 8 | - | - | 1,465 |
Apr | - | 3 | - | - | 332 | 582 | 16 | 1 | 5 | 23 | - | - | - | - | - | - | 962 |
May | 1 | 3 | - | - | 69 | 208 | 1 | - | - | 9 | - | - | - | - | - | - | 291 |
Jun | - | - | - | - | 3 | 10 | - | - | - | - | - | - | - | - | - | - | 13 |
Jul | - | - | - | - | 1 | - | - | - | - | - | - | - | - | - | - | - | 1 |
Aug | 3 | - | 7 | - | 10 | 2 | - | - | 1 | - | 5 | - | - | - | - | - | 28 |
Sep | - | 11 | 1 | - | 33 | 43 | - | 2 | 1 | - | 12 | - | - | - | - | - | 103 |
Oct | 2 | 88 | 8 | - | 124 | 817 | 20 | 1,151 | 1 | 11 | 70 | 1 | - | 2 | 2 | - | 2,297 |
Nov | - | 41 | - | - | 180 | 918 | 613 | 892 | 2 | 116 | 2 | 2 | - | 253 | - | - | 3,019 |
Dec | - | 10 | - | - | 101 | 372 | 243 | 91 | 2 | 50 | - | - | - | 86 | - | - | 955 |
Subtotal | 7 | 172 | 16 | - | 1,509 | 4,598 | 1,233 | 2,161 | 23 | 401 | 89 | 3 | - | 363 | 2 | - | 10,577 |
Total | 11 | 303 | 16 | 1 | 3,301 | 7,593 | 1,852 | 3,156 | 41 | 637 | 117 | 4 | 2 | 396 | 12 | 15 | 17,457 |
% | 0.1 | 1.7 | 0.1 | 0.0 | 18.9 | 43.5 | 10.6 | 18.1 | 0.2 | 3.6 | 0.7 | 0.0 | 0.0 | 2.3 | 0.1 | 0.1 | 100.0 |
C. ika = Cheladonta ikaoensis; E. kor = Euschoengastia koreaensis; L. ful = Leptotrombidium fuller; L. gem = Leptotrombidium gemiticulum; L. ori = Leptotrombidium orientale; L. pall = Leptotrombidium pallidum; L. palp = Leptotrombidium palpale; L. scu = Leptotrombidium scutellare; L. sub = Leptotrombidium subintermedium; L. zet = Leptotrombidium zetum; N. gar = Neotrombicula gardellai; N. jap = Neotrombicula japonica; N. kwa = Neotrombicula kwangneungensis; N. tam = Neotrombicula tamiyai; W. fra = Walchia fragilis; L. spp. = Leptotrombidium species.
Ot = Orientia tsutsugamushi.
C. ika = Cheladonta ikaoensis; E. kor = Euschoengastia koreaensis; L. ful = Leptotrombidium fuller; L. gem = Leptotrombidium gemiticulum; L. ori = Leptotrombidium orientale; L. pall = Leptotrombidium pallidum; L. palp = Leptotrombidium palpale; L. scu = Leptotrombidium scutellare; L. sub = Leptotrombidium subintermedium; L. zet = Leptotrombidium zetum; N. gar = Neotrombicula gardellai; N. jap = Neotrombicula japonica; N. kwa = Neotrombicula kwangneungensis; N. tam = Neotrombicula tamiyai; W. fra = Walchia fragilis; L. spp. = Leptotrombidium species.