A large-scale survey was conducted to investigate the infection status of fresh water fishes with
Recent trends of helminthic infections in the Republic of Korea are characterized by a remarkable decrease of soil-transmitted nematodiases and moderate endemicity of foodborne trematode (FBT) infections. Among FBT infections prevailing in the Republic of Korea, clonorchiasis has been known as the most important endemic disease, and its endemicity has maintained at relatively high levels in riverside areas [
Clonorchiasis is contracted by eating raw or undercooked fish intermediate hosts containing the metacercariae of
On the other hand, the survey on the infection status of FBT metacercariae in intermediate hosts is one of the important epidemiological indices together with surveys on adult worm infections in the definitive and reservoir hosts. Many Korean workers have investigated the infection status of
Surveyed areas were largely divided into 3 latitudinal regions of the Korean peninsula (
In western parts of Gangwon-do, we collected 678 freshwater
fishes (36 species) from 4 localities, Soyang-gang (Inje-gun in October 2003 and April 2004), Hongcheon-gang (Hongcheon-gun in October 2003, and July and October 2010), Hantan-gang (Cheolwon-gun in April 2005 and October 2010), and Hwa-gang (Cheolwon-gun in June 2010) in Gangwon-do. We also collected 865 fishes (32 species) from 5 localities of eastern parts of Gangwon-do, Sooip-cheon (Yanggu-gun), Namdae-cheon (Yangyang-gun), Dong-gang (Youngweol-gun), Osip-cheon, and Gagok-cheon (Samcheok-si) 2 times in June and October 2009. The numbers and species of fish examined are shown in
In middle regions, a total of 451 fishes (32 species) were collected from 3 sites, Gum-gang (Okcheon-gun in April and September 2006), Cheong-cheon (stream in Goisan-gun on June 2003) and Daecheong-ho (Lake, on June 2003), located in Chungcheongbuk-do. The numbers and species of fish examined are shown in
In western parts of southern localities, 452 freshwater fishes (35 species) were collected from 6 localities, Seomjin-gang (Gokseong-gun in September 2004 and May 2005) (Gurye-gun in September 2004), Youngsan-gang (Naju-si in October 2005), Tamjin-gang (Gangjin-gun and Jangheung-gun, in October 2005) and Boseong-gang (Boseong-gun in October 2005), in Jeollanam-do. The numbers and species of fish examined are shown in
All collected fishes with ice were transferred to the laboratory of the Department of Parasitology, Gyeongsang National University School of Medicine, Jinju, Korea. After identification of fish species [
The metacercariae of
A total of 50
A total of 68
Among 191 fishes (22 species) from Seomjin-gang in Gokseong-gun, 42 (13 species) were infected with 2,496
A total of 1,831
Total 175
Among 1,543 fish from northern areas, only 11 (0.7%) of 2 species,
In an analysis with an index fish,
As the second intermediate hosts of
The successful sampling of subjected materials is one of the important factors in epidemiological surveys. A satisfactory fish collection is not easy in surveys like the present study. Fish ecologies are variable by natural conditions, and collected fish species are different by the catching methods (netting, casting net, and trapping) and timings. Although a total of 4,071 freshwater fish were examined in the present study, the fish examined more than 200 in number were only 7 species, i.e.
By the present study, it is confirmed again that the southern areas are highly endemic for clonorchiasis in Korean peninsula [
On the other hand, in case of
Among the 47 fish species listed as the second intermediate hosts of
The positive rates and densities of
There have been few studies that examined the infection status of
Studies on the
Bae et al. [
This study was supported by an anti-communicable diseases control program (NIH 348-6111-215) and a project on the parasite fauna of the Republic of Korea and management of parasitic diseases cyber-musium (2008-E00165-00) of National Institute of Health, Ministry of Health and Welfare, the Republic of Korea. We thank Young-Kil Kim (Division of Public Health Policy, Province of Gyeongsangbuk-do) and Sook-Nam Hwang (Division of Microbiology, Ulsan Institute of Health and Environment), for their help in collection of freshwater fish, and A-Ra Cho, Hae-In Ryu, Jung-A Kim, and Hee-Joo Kim (Department of Parasitology, Gyeongsang National University School of Medicine, Jinju, Korea), for their help in examination of fishes.
The surveyed areas. The northern area located over 37° North Latitude is comprised of 7 administrative regions of Gangwon-do (① Inje-gun: Soyang-gang, ② Hongcheon-gun: Hongcheon-gang, ③ Cheolwon-gun: Hantan-gang and Hwa-gang, ④ Yanggu-gun: Sooip-cheon, ⑤ Yangyang-gun: Namdae-cheon, ⑥ Youngweol-gun: Dong-gang and ⑦ Samcheok-si: Osip-cheon and Gagok-cheon). The middle area located between 36° and 37° North Latitude is contained 3 regions of Chungcheongbuk-do (⑧ Okcheon-gun: Gum-gang, ⑨ Goisan-gun: Cheong-cheon and ⑩ Daecheong-ho), and 7 regions of Nakdong-gang (⑪ Ahndong-si, ⑫ Sangju-si, ⑬ Bonghwa-gun, ⑭ Yecheon-gun, ⑮ Youngyang-gun, ⑯ Youngdeok-gun and ⑰ Gunwi-gun) in Gyeongsangbuk-do. The southern area located below 36° North Latitude is comprised of 6 administrative regions of Jeollanam-do (⑱ Gokseong-gun: Seomjin-gang, ⑲ Gurye-gun: Seomjin-gang, ⑳ Naju-si: Youngsan-gang, ㉑ Gangjin-gun: Tamjin-gang, ㉒ Jangheung-gun: Tamjin-gang and ㉓ Boseong-gun: Boseong-gang), and ㉔ Ulsan Metropolitan City (Taehwa-gang) and ㉕ Sancheong-gun (Yangcheon-gang) in Gyeongsangnam-do.
Fishes
Species of fish | No. of fish collected from 6 localites |
||||||
---|---|---|---|---|---|---|---|
① | ②-1 | ②-2 | ③-1 | ③-2 | ③-3 | Total | |
Cypriniforms | |||||||
|
40 | 10 | 20 | 16 | 30 | 3 | 119 |
|
14 | 20 | 25 | 8 | 7 | 13 | 87 |
|
6 | - | 16 | 19 | 30 | 10 | 81 |
|
5 | - | 20 | 14 | 3 | 12 | 54 |
|
10 | 1 | 23 | 5 | 8 | 3 | 50 |
|
5 | 3 | 18 | 19 | - | 2 | 47 |
|
- | - | 20 | 4 | - | 8 | 32 |
|
6 | - | 2 | 2 | 3 | 5 | 18 |
|
- | 10 | - | - | - | 4 | 14 |
|
10 | - | 1 | 2 | - | - | 13 |
|
- | - | 6 | - | 6 | - | 12 |
|
5 | - | - | - | - | - | 5 |
|
- | - | - | 5 | - | - | 5 |
|
5 | - | 5 | ||||
|
3 | - | 2 | - | - | - | 5 |
|
1 | 3 | - | - | - | - | 4 |
|
- | - | - | 4 | - | - | 4 |
|
- | - | - | 1 | 3 | - | 4 |
|
- | - | - | 3 | - | - | 3 |
|
- | - | - | - | 1 | 2 | 3 |
|
3 | - | - | - | - | - | 3 |
|
- | - | - | 3 | - | - | 3 |
|
- | 3 | - | - | - | - | 3 |
|
- | - | - | - | 3 | - | 3 |
|
- | - | - | 2 | - | - | 2 |
|
- | - | - | - | 2 | - | 2 |
|
- | - | - | - | 1 | - | 1 |
|
- | - | - | - | 1 | - | 1 |
|
1 | - | - | - | - | - | 1 |
|
- | 1 | - | - | - | - | 1 |
Siluriformes | |||||||
|
4 | 10 | - | - | - | - | 14 |
|
3 | - | - | - | - | - | 3 |
Perciformes | |||||||
|
- | 15 | 20 | 3 | 5 | 7 | 50 |
|
7 | - | 11 | - | - | - | 18 |
|
- | 6 | 2 | - | - | - | 8 |
Total | 123 | 82 | 186 | 110 | 108 | 69 | 678 |
Total 678 freshwater fishes of 36 species were examined.
① Inje-gun (Soyang-gang); ②-1 Hongcheon-gun (Hongcheon-gang, 2003); ②-2 Hongcheon-gun (Hongcheon-gang, 2010); ③-1 Cheolwon-gun (Hantan-gang, 2005); ③-2 Cheolwon-gun (Hantan-gang, 2010); ③-3 Cheolwon-gun (Hwa-gang, 2010).
Fishes
Species of fish | No. of fish collected from 5 localities |
|||||
---|---|---|---|---|---|---|
④ | ⑤ | ⑥ | ⑦-1 | ⑦-2 | Total | |
Cypriniforms | ||||||
|
26 | 30 | 30 | 23 | 19 | 128 |
|
23 | 30 | 30 | - | 20 | 103 |
|
27 | - | 30 | 30 | 8 | 95 |
|
11 | 15 | 16 | - | 17 | 59 |
|
- | 30 | - | 21 | - | 51 |
|
25 | - | 25 | - | - | 50 |
|
10 | 3 | - | 1 | 25 | 39 |
|
14 | - | 16 | - | - | 30 |
|
11 | - | 10 | - | - | 21 |
|
- | - | 18 | - | - | 18 |
|
14 | 2 | - | - | - | 16 |
|
- | - | 13 | - | - | 13 |
|
- | - | 13 | - | - | 13 |
|
2 | - | 10 | - | - | 12 |
|
- | - | 10 | - | - | 10 |
|
- | - | - | 8 | - | 8 |
|
5 | - | - | - | - | 5 |
|
- | - | 5 | - | - | 5 |
|
- | - | - | 3 | - | 3 |
|
- | - | 3 | - | - | 3 |
|
- | - | 2 | - | - | 2 |
|
1 | - | - | - | - | 1 |
|
- | - | 1 | - | - | 1 |
Osmeriformes | ||||||
|
- | 25 | - | 29 | - | 54 |
Salmoniformes | ||||||
|
- | 5 | - | 2 | 3 | 10 |
Siluriformes | ||||||
|
10 | - | 3 | - | - | 13 |
|
- | - | 1 | - | - | 1 |
Perciformes | ||||||
|
17 | 10 | 15 | - | - | 42 |
|
- | - | - | 19 | 8 | 27 |
|
- | - | - | 15 | 9 | 24 |
|
- | - | - | 4 | - | 4 |
|
- | 4 | - | - | - | 4 |
Total | 196 | 154 | 251 | 155 | 109 | 865 |
Total 865 freshwater fishes of 32 species were examined.
5 localities, ④ Yanggu-gun (Sooip-cheon); ⑤ Yangyang-gun (Namdae-cheon); ⑥ Youngweol-gun (Dong-gang); ⑦-1 Samcheok-si (Osip-cheon); ⑦-2 Samcheok-si (Gagok-cheon).
Fishes
Species of fish | No. of fish collected from 3 localities |
|||
---|---|---|---|---|
⑧ | ⑨ | ⑩ | Total | |
Cypriniforms | ||||
|
43 | 20 | 2 | 65 |
|
49 | - | 2 | 51 |
|
41 | - | - | 41 |
|
34 | - | 5 | 39 |
|
28 | - | 4 | 32 |
|
25 | 6 | - | 31 |
|
21 | - | 10 | 31 |
|
14 | - | 10 | 24 |
|
20 | - | - | 20 |
|
20 | - | - | 20 |
|
12 | 5 | - | 17 |
|
- | 15 | - | 15 |
|
6 | - | 7 | 13 |
|
5 | - | - | 5 |
|
2 | 3 | - | 5 |
|
4 | - | - | 4 |
|
4 | - | - | 4 |
|
3 | - | - | 3 |
|
- | 2 | - | 2 |
|
2 | - | - | 2 |
|
1 | - | 1 | 2 |
|
1 | - | - | 1 |
|
1 | - | - | 1 |
|
1 | - | - | 1 |
|
1 | - | - | 1 |
|
- | 1 | - | 1 |
|
1 | - | - | 1 |
Siluriformes | ||||
|
1 | - | - | 1 |
Perciformes | ||||
|
12 | - | - | 12 |
|
2 | - | 1 | 3 |
|
2 | 1 | - | 3 |
Total | 356 | 53 | 42 | 451 |
Total 451 freshwater fishes of 32 species were examined.
3 localities, ⑧ Okcheon-gun (Gum-gang); ⑨ Goisan-gun (Cheong-cheon); ⑩ Daecheong-ho (Lake).
Fishes
Species of fish | No. of fish collected from 7 localities |
|||||||
---|---|---|---|---|---|---|---|---|
⑪ | ⑫ | ⑬ | ⑭ | ⑮ | ⑯ | ⑰ | Total | |
Cypriniforms | ||||||||
|
21 | - | 11 | 26 | 24 | 39 | 37 | 158 |
|
24 | 6 | 11 | 2 | 15 | 14 | 4 | 76 |
|
25 | - | 7 | - | 8 | 2 | 9 | 51 |
|
5 | - | - | - | - | 28 | 9 | 42 |
|
13 | - | 17 | - | 8 | - | - | 38 |
|
1 | 3 | - | 14 | - | 1 | 14 | 33 |
|
- | - | - | - | - | - | 29 | 29 |
|
3 | - | 10 | - | 15 | - | - | 28 |
|
- | 3 | - | 12 | - | - | 1 | 16 |
|
- | - | - | 10 | - | - | 4 | 14 |
|
- | 2 | - | 10 | - | - | 2 | 14 |
|
4 | - | - | - | 2 | - | 6 | 12 |
|
- | 2 | - | 10 | - | - | - | 12 |
|
8 | 2 | - | - | 1 | - | - | 11 |
|
- | 6 | - | 3 | - | - | 1 | 10 |
|
- | - | - | 4 | - | - | 6 | 10 |
|
- | - | - | - | - | - | 9 | 9 |
|
- | - | - | 9 | - | - | - | 9 |
|
- | - | 8 | - | - | - | - | 8 |
|
- | - | - | - | - | 6 | - | 6 |
|
- | 3 | - | 2 | - | - | - | 5 |
|
- | - | 1 | - | 2 | - | - | 3 |
|
- | - | - | - | - | 3 | - | 3 |
|
- | - | - | 2 | - | - | - | 2 |
|
- | - | - | - | 1 | - | - | 1 |
|
- | - | - | 2 | - | - | - | 2 |
|
- | - | - | - | - | - | 1 | 1 |
|
- | - | - | - | - | - | 1 | 1 |
Osmeriformes | ||||||||
|
- | - | - | - | - | 10 | - | 10 |
Siluriformes | ||||||||
|
- | - | 15 | - | - | - | - | 15 |
|
- | - | 10 | - | 1 | - | - | 11 |
|
1 | - | - | 8 | - | - | - | 9 |
Perciformes | ||||||||
|
6 | 10 | 6 | 11 | 6 | - | 3 | 42 |
|
- | 1 | - | 1 | - | - | - | 2 |
|
7 | 7 | 1 | 5 | 3 | - | - | 23 |
Total | 118 | 45 | 97 | 131 | 86 | 103 | 136 | 716 |
Total 716 freshwater fishes in 35 species were examined.
⑪ Ahndong-si; ⑫ Sangju-si; ⑬ Bonghwa-gun; ⑭ Yecheon-gun; ⑮ Youngyang-gun; ⑯ Youngdeok-gun; ⑰ Gunwi-gun.
Fishes
Species of fish | No. of fish collected from 6 localities |
||||||
---|---|---|---|---|---|---|---|
⑱ | ⑲ | ⑳ | ㉑ | ㉒ | ㉓ | Total | |
Cypriniforms | |||||||
|
42 | 1 | 20 | 10 | 10 | 1 | 84 |
|
13 | 7 | 10 | - | 2 | 2 | 34 |
|
4 | 25 | - | - | - | - | 29 |
|
12 | 7 | 3 | 2 | - | 3 | 27 |
|
12 | 1 | - | 6 | 3 | 2 | 24 |
|
8 | 3 | 3 | 3 | 3 | 2 | 22 |
|
21 | - | - | - | - | - | 21 |
|
- | 1 | 8 | - | 10 | - | 19 |
|
8 | - | - | 1 | 10 | - | 19 |
|
4 | - | - | 15 | - | - | 19 |
|
17 | 1 | - | - | - | - | 18 |
|
- | - | - | 8 | 10 | - | 18 |
|
2 | 6 | 4 | 3 | - | - | 15 |
|
12 | - | 1 | - | - | - | 13 |
|
3 | - | 8 | - | - | - | 11 |
|
- | 10 | - | - | - | - | 10 |
|
3 | - | 2 | - | - | 1 | 6 |
|
5 | - | - | - | - | - | 5 |
|
4 | - | - | - | - | - | 4 |
|
3 | - | - | - | - | - | 3 |
|
- | - | - | 3 | - | - | 3 |
|
- | - | - | - | 3 | - | 3 |
|
- | - | - | - | - | 3 | 3 |
|
2 | - | - | - | - | - | 2 |
|
- | 2 | - | - | - | - | 2 |
|
- | - | - | 1 | - | - | 1 |
|
1 | - | - | - | - | - | 1 |
|
- | - | - | - | - | 1 | 1 |
|
- | 1 | - | - | - | - | 1 |
Osmeriformes | |||||||
|
- | 2 | - | 6 | - | - | 8 |
Siluriformes | |||||||
|
- | - | - | - | - | 1 | 1 |
Perciformes | |||||||
|
7 | - | - | - | - | - | 7 |
|
5 | 1 | - | - | - | - | 6 |
|
- | - | 5 | - | - | - | 5 |
|
3 | - | 1 | - | 1 | 2 | 7 |
Total | 191 | 68 | 65 | 58 | 52 | 18 | 452 |
Total 452 freshwater fishes of 35 species were examined;
⑱ Gokseong-gun (Seomjin-gang); ⑲ Gurye-gun (Seomjin-gang); ⑳ Naju-si (Youngsan-gang); ㉑Gangjin-gun (Tamjin-gang); ㉒ Jangheung-gun (Tamjin-gang);㉓Boseong-gun (Boseong-gang).
Fishes
Species of fish | No. of fish collected from 3 localities |
||||
---|---|---|---|---|---|
㉔ | ㉕-1 | ㉕-2 | ㉕-3 | Total | |
Cypriniforms | |||||
|
- | 24 | 44 | 78 | 146 |
|
60 | 21 | 19 | 44 | 144 |
|
- | 34 | 16 | 60 | 110 |
|
4 | 34 | 20 | 32 | 90 |
|
5 | 36 | 13 | 18 | 72 |
|
- | 31 | 15 | 22 | 68 |
|
- | 25 | 13 | 10 | 48 |
|
25 | 7 | 2 | 3 | 37 |
|
- | 15 | - | 15 | 30 |
|
- | - | 2 | 9 | 11 |
|
5 | - | - | 1 | 6 |
|
- | - | 6 | - | 6 |
|
5 | - | - | - | 5 |
|
- | 3 | - | 2 | 5 |
|
- | - | 4 | - | 4 |
|
- | - | 4 | - | 4 |
|
- | - | 2 | 2 | 4 |
|
2 | - | 2 | - | 4 |
|
3 | - | - | - | 3 |
|
- | 2 | - | - | 2 |
|
- | - | 1 | - | 1 |
Perciformes | |||||
|
2 | 19 | 8 | 30 | 59 |
|
- | 2 | - | - | 2 |
|
8 | 8 | 8 | 24 | 48 |
Total | 119 | 261 | 179 | 350 | 909 |
Total 909 freshwater fishes of 24 species were examined;
㉔ Ulsan Metropolitan City (Taehwa-gang); ㉕-1 Sancheong-gun (Yangcheon-gang, 2006); ㉕-2 Sancheong-gun (Yangcheon-gang, 2007); ㉕-3 Sancheong-gun (Yangcheon-gang, 2010).
Prevalence and density of
Location and fish sp. | No. of fish examined | No. (%) of fish infected | No. of metacercariae detected |
||
---|---|---|---|---|---|
Total | Range | Average | |||
⑧ Gum-gang (River) | |||||
|
2 | 1 (50.0) | 20 | - | 20.0 |
|
25 | 1 (4.0) | 2 | - | 2.0 |
|
20 | 8 (40.0) | 15 | 1-4 | 1.9 |
|
41 | 4 (9.8) | 5 | 1-2 | 1.3 |
|
49 | 3 (6.1) | 3 | - | 1.0 |
|
34 | 1 (2.9) | 1 | - | 1.0 |
|
28 | 1 (3.6) | 1 | - | 1.0 |
|
2 | 1 (50.0) | 1 | - | 1.0 |
|
1 | 1 (100) | 1 | - | 1.0 |
|
1 | 1 (100) | 1 | - | 1.0 |
Subtotal | 203 | 22 (10.8) | 50 | 1-20 | 2.3 |
⑨ Cheong-cheon (Stream) in Goisan-gun | |||||
|
6 | 4 (66.7) | 23 | 2-12 | 5.8 |
|
20 | 1 (5.0) | 3 | - | 3.0 |
|
3 | 1 (33.3) | 1 | - | 1.0 |
Subtotal | 29 | 6 (20.7) | 27 | 1-12 | 4.5 |
Total | 232 | 28 (12.1) | 77 | 1-20 | 2.8 |
Prevalence and density of
Location and fish sp. | No. of fish examined | No. (%) of fish infected | No. of metacercariae detected |
||
---|---|---|---|---|---|
Total | Range | Average | |||
⑭ Yecheon-gun | |||||
|
2 | 2 (100) | 33 | 5-28 | 16.5 |
|
2 | 2 (100) | 19 | 2-17 | 9.5 |
|
2 | 1 (50.0) | 8 | - | 8.0 |
|
26 | 1 (3.8) | 4 | - | 4.0 |
|
12 | 1 (8.3) | 1 | - | 1.0 |
|
10 | 1 (10.0) | 2 | - | 2.0 |
|
3 | 1 (33.3) | 1 | - | 1.0 |
Subtotal | 57 | 9 (15.8) | 68 | 1-28 | 7.6 |
⑮ Youngyang-gun | |||||
|
15 | 15 (100) | 3,736 | 13-630 | 249.1 |
|
1 | 1 (100) | 56 | - | 56.0 |
|
2 | 2 (100) | 54 | 1-53 | 27.0 |
|
8 | 7 (87.5) | 45 | 1-16 | 6.4 |
|
2 | 1 (50.0) | 4 | - | 4.0 |
|
24 | 5 (20.8) | 13 | 1-6 | 2.6 |
Subtotal | 52 | 31 (59.6) | 3,908 | 1-630 | 126.1 |
⑰ Gunwi-gun | |||||
|
1 | 1 (100) | 2,105 | - | 2,105 |
|
9 | 9 (100) | 7,463 | 385-1,875 | 829.2 |
|
4 | 4 (100) | 3,279 | 329-1,180 | 819.8 |
|
29 | 29 (100) | 6,872 | 9-875 | 237.0 |
|
2 | 2 (100) | 136 | 54-82 | 68.0 |
|
37 | 9 (24.3) | 126 | 1-77 | 14.0 |
|
1 | 1 (100) | 11 | - | 11.0 |
|
4 | 4 (100) | 34 | 3-13 | 8.5 |
|
6 | 6 (100) | 43 | 2-11 | 7.2 |
|
9 | 1 (11.1) | 3 | - | 3.0 |
|
9 | 1 (11.1) | 2 | - | 2.0 |
|
6 | 1 (16.7) | 1 | - | 1.0 |
|
3 | 1 (33.3) | 1 | - | 1.0 |
|
1 | 1 (100) | 1 | - | 1.0 |
Subtotal | 111 | 70 (63.1) | 20,077 | 1-2,105 | 286.8 |
Total | 220 | 110 (50.0) | 24,053 | 1-2,105 | 218.7 |
Prevalence and density of
Location and fish sp. | No. of fish examined | No. (%) of fish infected | No. of metacercariae detected |
||
---|---|---|---|---|---|
Total | Range | Average | |||
⑱ Gokseong-gun | |||||
|
2 | 2 (100) | 604 | 259-345 | 302.0 |
|
4 | 2 (50.0) | 379 | 20-359 | 189.5 |
|
42 | 1 (2.4) | 118 | - | 118.0 |
|
12 | 10 (83.3) | 1,139 | 1-275 | 113.9 |
|
12 | 3 (25.0) | 164 | 20-93 | 54.7 |
|
3 | 2 (66.7) | 27 | 2-25 | 13.5 |
|
4 | 3 (75.0) | 31 | 4-16 | 10.3 |
|
2 | 2 (100) | 7 | 2-5 | 3.5 |
|
1 | 1 (100) | 2 | - | 2.0 |
|
4 | 2 (50.0) | 4 | - | 2.0 |
|
17 | 11 (64.7) | 18 | 1-3 | 1.6 |
|
13 | 1 (7.7) | 1 | - | 1.0 |
|
3 | 2 (66.7) | 2 | - | 1.0 |
Subtotal | 119 | 42 (35.3) | 2,496 | 1-359 | 59.4 |
⑲ Gurye-gun | |||||
|
1 | 1 (100) | 377 | - | 377.0 |
|
25 | 19 (76.0) | 771 | 1-351 | 40.6 |
|
10 | 10 (100) | 217 | 6-62 | 21.7 |
|
2 | 1 (50.0) | 14 | - | 14.0 |
|
1 | 1 (100) | 4 | - | 4.0 |
|
6 | 1 (16.7) | 3 | - | 3.0 |
|
3 | 2 (66.7) | 2 | - | 1.0 |
|
7 | 1 (14.3) | 1 | - | 1.0 |
|
1 | 1 (100) | 1 | - | 1.0 |
Subtotal | 56 | 37 (66.1) | 1,390 | 1-377 | 37.6 |
Total | 175 | 79 (45.1) | 3,886 | 1-377 | 49.2 |
Prevalence and density of
Location and fish sp. | No. of fish examined | No. (%) of fish infected | No. of metacercariae detected |
||
---|---|---|---|---|---|
Total | Range | Average | |||
⑳ Youngsan-gang in Naju-si | |||||
|
1 | 1 (100) | 815 | - | 815.0 |
|
5 | 5 (100) | 730 | 2-460 | 146.0 |
|
4 | 4 (100) | 215 | 23-107 | 53.8 |
|
2 | 1 (50.0) | 28 | - | 28.0 |
|
3 | 3 (100) | 24 | 1-12 | 8.0 |
|
3 | 2 (66.7) | 10 | 1-9 | 5.0 |
|
20 | 1 (5.0) | 2 | - | 2.0 |
|
8 | 5 (62.5) | 6 | 1-2 | 1.2 |
|
10 | 1 (10.0) | 1 | - | 1.0 |
Subtotal | 56 | 23 (41.1) | 1,831 | 1-460 | 79.6 |
㉑ Tamjin-gang in Gangjin-gun | |||||
|
6 | 6 (100) | 2,520 | 95-846 | 420.0 |
|
15 | 15 (100) | 5,342 | 65-682 | 356.1 |
|
3 | 3 (100) | 122 | 30-52 | 40.7 |
|
1 | 1 (100) | 6 | - | 6.0 |
|
8 | 5 (62.5) | 14 | 1-9 | 2.8 |
|
3 | 3 (100) | 6 | 1-3 | 2.0 |
|
2 | 2 (100) | 4 | 1-3 | 2.0 |
|
3 | 3 (100) | 5 | 1-3 | 1.7 |
|
10 | 1 (10.0) | 1 | - | 1.0 |
Subtotal | 51 | 39 (76.5) | 8,020 | 1-846 | 205.6 |
㉓ Boseong-gang in Boseong-gun | |||||
|
2 | 2 (100) | 157 | 9-148 | 78.5 |
|
2 | 1 (50.0) | 2 | - | 2.0 |
|
3 | 1 (33.3) | 2 | - | 2.0 |
|
1 | 1 (100) | 1 | - | 1.0 |
Subtotal | 8 | 5 (62.5) | 162 | 1-148 | 32.4 |
Total | 115 | 67 (58.3) | 10,013 | 1-846 | 149.4 |
Prevalence and density of
Year examined and fish sp. | No. of fish examined | No. (%) of fish infected | No. of metacercariae detected |
||
---|---|---|---|---|---|
Total | Range | Average | |||
2006 | |||||
|
24 | 24 (100) | 19,044 | 324-1,408 | 793.5 |
|
7 | 7 (100) | 1,775 | 100-380 | 253.6 |
|
34 | 34 (100) | 3,643 | 2-313 | 107.2 |
|
3 | 3 (100) | 187 | 37-112 | 62.3 |
|
15 | 10 (66.7) | 335 | 1-83 | 33.5 |
|
25 | 18 (72.0) | 100 | 1-44 | 5.6 |
|
31 | 7 (22.6) | 13 | 1-3 | 1.9 |
|
34 | 4 (11.8) | 6 | 1-3 | 1.5 |
|
21 | 3 (14.3) | 3 | - | 1.0 |
Subtotal | 194 | 110 (56.7) | 25,106 | 1-1,408 | 228.2 |
2007 | |||||
|
44 | 44 (100) | 28,294 | 106-2,345 | 707.4 |
|
2 | 2 (100) | 658 | 178-480 | 329.0 |
|
2 | 2 (100) | 551 | 145-406 | 275.5 |
|
2 | 2 (100) | 298 | 89-209 | 149.0 |
|
16 | 13 (81.3) | 817 | 1-197 | 62.9 |
|
1 | 1 (100) | 11 | - | 11.0 |
|
2 | 2 (100) | 14 | - | 7.0 |
|
6 | 6 (100) | 35 | 1-16 | 5.8 |
|
8 | 1 (12.5) | 4 | - | 4.0 |
|
15 | 8 (53.3) | 23 | 1-10 | 2.9 |
|
19 | 1 (5.3) | 2 | - | 2.0 |
|
4 | 2 (50.0) | 4 | 1-3 | 2.0 |
|
13 | 9 (69.2) | 16 | 1-4 | 1.8 |
|
13 | 1 (7.7) | 1 | - | 1.0 |
|
8 | 1 (12.5) | 1 | - | 1.0 |
Subtotal | 155 | 95 (61.3) | 30,729 | 1-2,345 | 323.4 |
2010 | |||||
|
2 | 2 (100) | 542 | 240-302 | 271.0 |
|
78 | 71 (91.0) | 13,143 | 1-1,286 | 185.1 |
|
3 | 3 (100) | 235 | 48-131 | 78.3 |
|
1 | 1 (100) | 45 | - | 45.0 |
|
2 | 2 (100) | 51 | 15-36 | 25.5 |
|
9 | 8 (88.9) | 191 | 2-59 | 23.9 |
|
15 | 11 (73.3) | 263 | 4-98 | 23.9 |
|
60 | 55 (91.7) | 994 | 1-136 | 18.1 |
|
44 | 5 (11.4) | 12 | 1-8 | 2.4 |
|
22 | 17 (77.3) | 37 | 1-6 | 2.2 |
|
10 | 1 (10.0) | 1 | - | 1.0 |
Subtotal | 246 | 176 (71.5) | 15,514 | 1-1,286 | 88.1 |
Total | 595 | 381 (64.0) | 71,349 | 1-2,345 | 187.3 |
Comparative prevalence
Items | Infection status (%) in fishes from |
|||
---|---|---|---|---|
Northern | Middle | Southern | Total | |
No. (%) of fish examined | 1,543 (37.9) | 1,167 (28.7) | 1,361 (33.4) | 4,071 (100) |
Total positive rate (%) | 11/1,543 (0.7) | 149/1,167 (12.8) | 538/1,361 (39.5) | 698/4,071 (17.1) |
Overall metacercarial density/fish | 2.6 | 163.7 | 158.8 | 157.4 |
Positive rate (%) of |
9/146 (6.2) | 34/107 (31.8) | 158/170 (92.9) | 201/423 (47.5) |
Metacercarial density in |
2.8 | 214.7 | 409.3 | 358.2 |
Positive rate (%) of |
0/247 (0) | 17/223 (7.6) | 13/228 (5.7) | 30/698 (4.3) |
Metacercarial density in |
0 | 8.6 | 10.7 | 9.5 |
Prevalence: no. of fish infected/no. of fish examined×100; density: mean no. of metacercariae per infected fish.