A nationwide survey of naturally produced oysters for infection with Gymnophalloides seoi metacercariae.
A nationwide survey was performed to know the geographical distribution of Gymnophalloides seoi (Digenea: Gymnophallidae) metacercariae in Korea, by examining the infection status of locally produced oysters, Crassostrea gigas. A total of 24 coastal areas (myons) of 14 guns ( = counties) in Kyonggi-do, Chollabuk-do, Chollanam-do, Kyongsangnam-do, Kyongsangbuk-do, or Kangwon-do, where natural oysters are produced but G. seoi has never been reported, and 13 areas (myons) of Shinan-gun, Chollanam-do, nearby the known endemic area, were surveyed. Oysters from nonendemic areas were free from G. seoi infection, except Byonsan-myon of Buan-gun, Chollabuk-do, where one of 50 oysters examined was infected with 15 metacercariae of G. seoi. In Shinan-gun, oysters from 10 areas including Aphae-myon ( = township) and Anjwa-myon were infected with the metacercariae, with the infection rate ranging from 1.7% to 100% by areas. The intensity of infection was the highest in Aphae-myon. 785.9 metacercariae per oyster. The results indicate that high prevalence of G. seoi is confined to Shinan-gun, but low grade prevalence is also present in adjacent areas such as Buan-gun, Chollabuk-do.
Lee
S H
SH
Department of Parasitology, Seoul National University College of Medicine, Korea.
Sohn
W M
WM
Hong
S J
SJ
Huh
S
S
Seo
M
M
Choi
M H
MH
Chai
J Y
JY
D000818:Animals; D007723:Korea; D010125:Ostreidae / Q000469:parasitology*; D015995:Prevalence; D014200:Trematoda / Q000302:isolation & purification*