JaLCDOI 10.18926/fest/11424
FullText URL 011_009_014.pdf
Author Nishina Tomohiko| Tian Tian Chen| Fujita Kazutoshi| Ishikawa, Hirofumi|
Abstract The red fox (Vulpes vulepes) and the vole ( Clethrionomys refocanus) are principal hosts of Echinococcus multilocularis in Hokkaido, Japan. How protoscoleces increases in voles and the level of immunity in foxes remain unknown because of the lack of survey data, so that it is important to clarify these mecahnisms in order to develop control strategies against E. multilocularis. In this study, the growth of protoscoleces in the infected voles was approximated as the logistic curve, the level of immunity in the fox was assumed to depend on the experience of the infection with E. multilocularis, and the worm burden in the fox was assumed to be governed by the amount of protoscoleces in the vole. Our model showed that the population densities of the hosts and the level of immunity influenced the prevalence of the E. multilocularis.
Keywords Echinococcus multilocularis protoscoleces immunity worm burden stochastic model
Publication Title 岡山大学環境理工学部研究報告
Published Date 2006-03-15
Volume volume11
Issue issue1
Start Page 9
End Page 14
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002314034
JaLCDOI 10.18926/fest/11422
FullText URL 011_001_007.pdf
Author Fujita Kazutoshi| Tian Tian Chen| Nishina Tomohiko| Ishikawa, Hirofumi|
Abstract Plasmodium vivax re-emerged in 1993 near the demilitarized zone (DMZ) in South Korea, although P. vivax malaria disappeared in South Korea in 1979. The re-emergence of malaria in South Korea is believed to have originated from infection by mosquitoes from North Korea across the DMZ. The principal vector of P. vivax in the Korean Peninsula is Anopheles sinensis. The density of An. sinensis has a peak during the second week of July. The North Korean strain of P. vivax has 2 characteristics: a wide distribution of the terms of relapse and a high rate of relapse. Therefore, we may well wonder why the incidence of malaria is concentrated in summer, especially in August. Mathematical models in North Korea and South Korea were constructed in which the South Korean model was affected unidirectionally by the North Korean model. We carried out simulations of the model for the Paju-shi and Yonchon-gun situations near the DMZ region. The simulation results followed the time-course of the re-emergence of P. vivax there, and revealed the mechanism of the elevation of the incidence of P. vivax in summer.
Keywords DMZ Korea model Plasmodium vivax re-emergence
Publication Title 岡山大学環境理工学部研究報告
Published Date 2006-03-15
Volume volume11
Issue issue1
Start Page 1
End Page 7
ISSN 1341-9099
language 英語
File Version publisher
NAID 40007297549