A nationwide survey of naturally produced oysters for infection with <i>Gymnophalloides seoi</i> metacercariae

, Lee, S H; , Sohn, W M; , Hong, S J; , Huh, S; , Seo, M; , Choi, M H; , Chai, J Y

doi:1996.34.2.107

Korean J Parasito > Volume 34(2):1996 > Article

Original Article


Korean J Parasitol. 1996 Jun;34(2):107-112. English. Published online Jun 20, 1996. http://dx.doi.org/10.3347/kjp.1996.34.2.107
Copyright © 1996 by The Korean Society for Parasitology


A nationwide survey of naturally produced oysters for infection with Gymnophalloides seoi metacercariae
S H Lee,¹W M Sohn,²S J Hong,³S Huh,⁴M Seo,¹M H Choi,¹ and J Y Chai^*¹
¹Department of Parasitology, Seoul National University College of Medicine, Seoul 110-799, Korea.

Received April 10, 1996; Accepted May 10, 1996.
Abstract
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.

Figures


	Fig. 1 Map showing the areas where naturally produced oysters were collected and examined for G. seoi metacercariae. Boxed area shows Shinan-gun, the known endemic area, which is shown in detail in Fig. 2 (⊕: positive for G. seoi infection, ⊖: negative for G. seoi infection).


	Fig. 2 Geographical distribution of G. seoi infection in oysters from Shinan-gun (⊕: positive for G. seoi infection, ⊖: negative for G. seoi infection).

Tables


	Table 1 Results of oyster examination for G. seoi metacercariae in non-endemic areas


	Table 2 The infection status of oysters from Shinan-gun, Chollanam-do, with G. seoi metacercariae

References


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