Main results to date


1) We found that gentle gradient lakeshores provide a wide range of thermal conditions, suggesting that
 fish can choose tempertures to alleviate stress associated with unfavorable water temperatures, and
 thus reduce susceptibility to KHV (Yamanaka et al., 2010).

2) We established an innnovative method to quantitatively detect KHV in natural environments
 (Minamoto et al., 2009 (Fig.3);Honjo et al., 2010). The method revealed that since it was first
 detected in 2003, KHV is now found throughout the Lake Biwa ecosystem, including in plankton and
 sediment, lagoons and ponds, and now in almost all the rivers in Japan. We demonstrated that
 it is impossible to eliminate KHV, but that precautionary environmental management can eliminate
 "fertile" disease environments.
 

3) We have developed a preliminary break-through method allowing determination of the number and
 location of carp in their natural environments.

4) We found that breeding habitats can became hot spots for transmission of infectious diseases if hosts
 aggregate for mating and pathogen activation occurs during the host breeding season (Uchii et al.,
 2011
) (Photo 3).
 

5) We developed a non-invasive method (i.e. a method that does not require handling fish) to quantify
 how water conditions stress carp. Using this method we found that changes in water temperature do
 induce stress.

6) We applied a Based on our assessment of KHV disease in Lake Biwa, we applied our conceptual model
 of linked environment-pathogen-human interactions to Lake Erhai, China, schistosomiasis in Kenya,
 fish diseases in the Ping River at Chaing Mai, Thailand (Photo 4), and Legionella disease (Yamaguchi et
 al., 2010), MRSA, Norovirus disease, and nontuberculous mycobacteria disease (Ichijo et al., 2010) in
 Japan. These applications helped us understand how pathogens interact with humans and suggested
 enviromental conditions that might prevent disease outbreaks and spread as well asstrategies for safe
 coexistence of humans with pathogens.
 

7) By combining the results from each work group, ranging from molecular biology to envirnmental
 sciences to human society, we are providing evidence to support the hypothesis that anthropogenic
 encironmental changes promote disease outbreaks.

8) We have presented our findings at national and international conferences of the linkages between the
 environment, pathogens and humans, emphsizing their significance to preventionand control of
 infectious disease.


Research background and objectives

 The rapid spread of emerging infectious diseases is a serious global environmental problem that is not only threatening humans, wildlife, and livestock worldwide, but also inducing economical loss and collapse of ecosystems. This project has study has three objectives, in the following successive order:
 (1) To verify the hypothesis that anthropogenic environmental changes mediate disease outbreaks and spread by analyzing the lakeshore degradation- koi herpesvirus (KHV)–human linkage as a case study, and develop a conceptual infectious disease model of the environment-pathogen–human linkage (Figs. 1 and 2),
 (2) To describe the link between the environment, pathogens, and humans for other infectious diseases based on the conceptual infectious disease model derived from KHV disease (Fig. 2) in order to understand the common structure of disease outbreaks,
 (3) To suggest how interactions between pathogens and humans can be modified to prevent disease outbreaks and mitigate the human and environmental damage associated with infectious diseases to realize a long-term societal security. (Fig. 2).

 



The most significant findings or outcomes of the study

 Specific significant outcomes are as follows:
 1) Innovative methods were established to describe the environment–pathogen–human linkage.
 2) We partially verified the hypothesis that anthropogenic alterations of the environment facilitate infectious diseases.
 3) The conceptual infectious disease model of the environment–pathogen–human linkage derived from KHV disease in Lake Biwa was applicable to other infectious disease cases.
 4) We showed that it was impossible to eradicate KHV. Thus, precautionary environmental management is needed to eliminate “fertile” disease environments to alleviate human and environmental damage associated with infectious disease.


Research Communications>

 We shared our research outputs with international and national academic communities and society.
The concept of the environment–pathogen–human linkage was introduced to academic communities and society by publishing a general paper (Kawabata et al., 2011) and more than 30 papers on individual subjects involved in the linkage, editing 10 special articles (Kawabata 2011; Kawabata 2011) for an international journal, organizing five international conferences and presenting at these events. These activities formed the base of an international alliance of researchers to study ‘environmental diseases’ (Environment–pathogen–human–linkage) and promote activities that could help alleviate infectious diseases worldwide.




 *Other research work see "here", please.



©2006-2012

Effects of Environmental Change on Interactions
between Pathogens and Humans.
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