렙토스피라증은 특정 지역에 국한하지 않고 전 세계적으로 발생하고 있는 인수 공통감염병으로 매년 수많은 사망자가 보고되고 있는 질병이다. 최근에는 수상레저와 캠핑 등 다양한 취미활동의 증가로 인해 점차 유행양상에 변화가 있다는 보고가 있어, 이에 광주지역 내 렙토스피라증의 유행양상을 살펴보기 위하여 렙토스피라증의 주요 매개체인 야생들쥐가 보유할 수 있는 렙토스피라균의 분자역학적 연구를 통해 병원체의 종 및 야생들쥐에서의 유병률을 조사하였다. 4년동안 (2015.9~2019.12) 매월 두 지역 (광산구 서봉동, 북구 생용동)에서 환경별로 5개 지점을 선정하여 야생들쥐를 포획하여 연구를 수행하였다. 총 801마리의 야생들쥐를 포획하였으며 그 중 Apodemus agrarius가 699마리, Crocidura lasiura가 69마리, Myodes regulus가 33마리를 차지하였으며 계절별로는 봄 200마리, 여름 192마리, 가을 205마리, 겨울에 204마리가 포획되었다. 렙토스피라균의 유전자 검출은 FlaB, SecY, 16srRNA를 기반으로 한 Conventional PCR을 통해 이루어졌으며 렙토스피라균의 FlaB, SecY, 16SrRNA 유전자를 1개 이상 가지고 있는 야생들쥐는 총 26마리였고, 이 중 FlaB, SecY, 16SrRNA 유전자 3개 모두 검출된 개체수는 19마리, FlaB와 16SrRNA 유전자 2개가 검출된 개체수는 1마리, FlaB와 SecY 유전자 2개가 검출된 개체수는 1마리, SecY와 16SrRNA 유전자 2개가 검출된 개체수는 4마리, 16SrRNA만 검출된 개체수는 1마리였다. FlaB 유전자에 대한 염기서열분석결과 총 21마리 중 5마리가 Leptospira borgpetesenii, 16마리는 렙토스피라균으로 구분되었다. SecY 유전자에 대해서는 총 세 그룹으로 나누어졌으며 총 24마리 중 19마리가 렙토스피라균, 3마리는 Leptospira interrogans, 2마리는 Leptospira biflexa로 나눠졌다. 16SrRNA 유전자에 대해서는 총 25마리 중 7마리가 Leptospira borgpetesenii, 18마리는 Leptospira interrogans로 구분되었다. 야생들쥐에서 렙토스피라균의 감염과 4년간의 계절요인과의 분석결과 특정 계절과의 상관 관계는 보이지 않아 연중 주의해야할 것으로 판단되며, 광주지역 내 기후변화와 관련하여 의미있는 결과분석을 위해서는 지속적인 모니터링이 필요할 것으로 본다.

Leptospira isolated from the patients with so called epidemic pulmonary hemorrhagic fever were comparatively studied with standard strains obtained from ATCC. The specific aim of this study was to clarify the morphologic heterogeneity of the isolates, i. e., coexistence of spiral forms in both handness, right and left, rod and spherical forms in their population by comparing them with those of the ATCC strains. No differences between our strains and ATCC strains were noticed in their growth characteristics, responses to the culture media, temperature, antibiotics and antifungal agents. Furthermore, the morphologic heterogeneity had been repeatedly observed even in cultures of standard ATCC strains, which had been noticed in the cultures of bacteria isolated in this laboratory. The serologic analysis of our isolates demonstrated that the bacteria reacted with L. icterohaemorrhagiae and L. australis regardless their differences in time of isolation(1984, 1985). Thus, it was concluded that the spiral bacteria isolated in this laboratory are Leptospira of a new serovar which still remained to be determined. And the previous reports on the morphology of the Leptospira, which described that the Leprospira population has only spiral forms with right. handed coils might be reconsidered.

Leptospirosis is the most wide spread zoonosis worldwide; it is present in all continents except Antarctica and evidence for the carriage of Leptospira has been found in virtually all mammalian species examined. Humans most commonly become infected through occupational, recreational, or domestic contact with the urine of carrier animals, either directly or via contaminated water or soil. Leptospires are thin, helical bacteria classified into at least 12 pathogenic and 4 saprophytic species, with more than 250 pathogenic serovars. Immunity following infection is generally, but not exclusively, mediated by antibody against leptospiral LPS and restricted to antigenically related serovars. Vaccines currently available consist of killed whole cell bacterins which are used widely in animals, but less so in humans. Current work with recombinant protein antigens shows promise for the development of vaccines based on defined protective antigens. The cellular and molecular basis for virulence remains poorly understood, but comparative genomics of pathogenic and saprophytic species suggests that Leptospira expresses unique virulence determinants. However, the recent development of defined mutagenesis systems for Leptospira heralds the potential for gaining a much improved understanding of pathogenesis in leptospirosis.

Ribosomal DNA fingerprints from 103 pathogenic Leptospira strains were examined using EcoRI restriction and fragment length polymorphisms of rRNA genes. Sixty-nine new leptospiral ribotypes were described, in addition to 49 previously observed. Except for 5 strains, a good correlation between DNA homology data and ribotyping was observed. The genospecies of 31 reference strains could be presumed, since they shared 13 ribotypes with strain(s) previously studied by DNA homology. Furthermore, the definition of common rRNA hybridization fragments in each recognized DNA hybridization group provides information about the status of Leptospira reference strains yet to be classified. With 118 ribotypes now defined among the validated serovar reference strains, rRNA fingerprints constitute a database for subtyping Leptospira species.