• Parasites, Hosts and Diseases
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• 제58권3호
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• pp.267-278
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• 2020

The heterogeneity and complexity of malaria involves political and natural environments, socioeconomic development, cross-border movement, and vector biology; factors that cannot be changed in a short time. This study aimed to assess the impact of economic growth and cross-border movement, toward elimination of malaria in Yunnan Province during its pre-elimination phase. Malaria data during 2011-2016 were extracted from 18 counties of Yunnan and from 7 villages, 11 displaced person camps of the Kachin Special Region II of Myanmar. Data of per-capita gross domestic product (GDP) were obtained from Yunnan Bureau of Statistics. Data were analyzed and mapped to determine spatiotemporal heterogeneity at county and village levels. There were a total 2,117 malaria cases with 85.2% imported cases; most imported cases came from Myanmar (78.5%). Along the demarcation line, malaria incidence rates in villages/camps in Myanmar were significantly higher than those of the neighboring villages in China. The spatial and temporal trends suggested that increasing per-capita GDP may have an indirect effect on the reduction of malaria cases when observed at macro level; however, malaria persists owing to complex, multi-faceted factors including poverty at individual level and cross-border movement of the workforce. In moving toward malaria elimination, despite economic growth, cooperative efforts with neighboring countries are critical to interrupt local transmission and prevent reintroduction of malaria via imported cases. Cross-border workers should be educated in preventive measures through effective behavior change communication, and investment is needed in active surveillance systems and novel diagnostic and treatment services during the elimination phase.

• Parasites, Hosts and Diseases
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• 제55권5호
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• pp.473-480
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• 2017

Plasmodium vivax merozoite surface protein-1 (PvMSP1) gene codes for a major malaria vaccine candidate antigen. However, its polymorphic nature represents an obstacle to the design of a protective vaccine. In this study, we analyzed the genetic polymorphism and natural selection of the C-terminal 42 kDa fragment within PvMSP1 gene ($PvMSP1_{42}$) from 77 P. vivax isolates, collected from imported cases of China-Myanmar border (CMB) areas in Yunnan province and the inland cases from Anhui, Yunnan, and Zhejiang province in China during 2009-2012. Totally, 41 haplotypes were identified and 30 of them were new haplotypes. The differences between the rates of non-synonymous and synonymous mutations suggest that $PvMSP1_{42}$ has evolved under natural selection, and a high selective pressure preferentially acted on regions identified of $PvMSP1_{33}$. Our results also demonstrated that $PvMSP1_{42}$ of P. vivax isolates collected on China-Myanmar border areas display higher genetic polymorphisms than those collected from inland of China. Such results have significant implications for understanding the dynamic of the P. vivax population and may be useful information towards China malaria elimination campaign strategies.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.677-681
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• 2013

Paragonimiasis is an important food-borne parasitic zoonosis caused by infection with lung flukes of the genus Paragonimus. Of the 7 members of the genus known in Thailand until recently, only P. heterotremus has been confirmed as causing human disease. An 8th species, P. pseudoheterotremus, has recently been proposed from Thailand, and has been found in humans. Molecular data place this species as a sister species to P. heterotremus, and it is likely that P. pseudoheterotremus is not specifically distinct from P. heterotremus. In this study, we collected metacercariae of both nominal species (identification based on metacercarial morphology) from freshwater crabs from Phetchabun Province in northern Thailand, Saraburi Province in central Thailand, and Surat Thani Province in southern Thailand. In addition, we purchased freshwater crabs imported from Myanmar at Myawaddy Province, western Thailand, close to the Myanmar-Thailand border. The DNAs extracted from excysted metacercariae were PCR-amplified and sequenced for ITS2 and cox1 genes. The ITS2 sequences were nearly identical among all samples (99-100%). Phylogenies inferred from all available partial cox1 sequences contained several clusters. Sequences from Indian P. heterotremus formed a sister group to sequences from P. pseudoheterotremus-type metacercariae. Sequences of P. heterotremus from Thailand, Vietnam, and China formed a separate distinct clade. One metacercaria from Phitsanulok Province was distinct from all others. There is clearly considerable genetic variation in the P. heterotremus complex in Thailand and the form referred to as P. pseudoheterotremus is widely distributed in Thailand and the Thai-Myanmar border region.

• 적정기술학회지
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• 제6권1호
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• pp.21-27
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• 2020

아프리카에서 시작돼 전 세계를 위협하는 ASF는 2018년 중국지역에서 발생해 아시아에 상륙하였고 2019년 5월 북한이 OIE에 ASF를 정식신고 함으로써 한반도 축산안보에 엄중한 위협으로 되었다. 1921년 영국의 수의병리학자 몽고메리는 동아프리카에서 풍토병으로 존재하던 치사율이 높은 바이러스에 의한 열성 돼지열병에 '아프리카돼지열병 African swine fever(ASF),'이라는 이름을 달아 세상에 알렸다. 아프리카지역에서 풍토병으로 유행하던 ASF는 1957년경 포르트갈에 상륙하여 포르투갈 리스본의 농장을 휩쓸었다. ASF는 계속하여 스페인과 포르투갈에 정착하여 1990년대 말까지 40년 동안 피해를 주었으며, 1978년에 이탈리아의 사르디니아섬에 상륙하여 현재진행형이다. 2007년에 흑해 연안의 죠지아 공화국의 포티항구에 상륙한 바이러스는 러시아까지 퍼졌고, 2018년에 중국에 침입하여 막대한 피해를 주면서 베트남, 라오스, 미얀마 등지로 급속히 퍼지다가 2019년 5월 북한에서 발병하여 전국에 확산되어 양돈업계에 막대한 피해를 주었으며 현재 진행형이다. 북한에서의 발병사실 확인후 불과 3개월 만에 2019년 9월 16일 파주와 연천의 농가에서 발병이 확인되면서 한국도 ASF발병국의 오명을 가지게 되었으며 ASF의 전국확산은 막았지만 야생 멧돼지에서 현재 진행형이다. 남북한에서 현재 진행중인 ASF가 토착화된다면 양돈산업은 물론 한반도 경제에 막대한 피해를 주는 역대 급 재앙으로 될 것이다. 현재의 상황상 ASF 발병으로 인한 위험요인을 배제하고, 남한지역에 국한된 수의방역에만 치중할 수 없다. 현재 북한의 열악한 수의방역현실로는 ASF발생으로 인한 양돈업계의 피해를 방지하기 어렵고, 지리적으로 각종 유행성 전염병의 발병위험이 높은 중국과 인접되어 있어 국경지역에 대한 검역과 방역을 남북한이 공동으로 진행하여야 할 필요성이 제기된다. 우선 한반도공동방역체계를 구축하기전 과제로 ASF 및 기타 질병에 대한 신속한 정보교류와 교육이 필요하다고 생각한다. 북한의 ASF발생지역 및 중국, 러시아 접경지역에 대한 철저한 방역과 소독을 실시하고 유통되는 가축 및 축산물에 대한 철저한 검역과 통제 등을 공동으로 진행하는 것이 중요하다. 모든 수단과 방법을 동원하여 한반도에서 ASF의 장기화를 막아 한반도 축산안보를 보장하기 위한 남북한 수의방역업계의 협력이 필수적이다.