Zoonotic infections and biological safety in southern Kyrgyzstan
Molecular detection and identification of zoonotic bacterial infections in rodents and their ectoparasites in southern Kyrgyzstan
Tech Area / Field
- BIO-SFS/Biosafety and BioSecurity/Biotechnology
- MED-DIS/Disease Surveillance/Medicine
3 Approved without Funding
Republican Center of Quarantine and Especially Dangerous Infections / Antiplague Department, Kyrgyzstan, Osh
- Department of Zoology and Ecology of Osh State University, Kyrgyzstan, Osh
- Centers for Disease Control and Prevention (CDC) / National Center for Infectious Diseases/ Division of Vector-Born Infectious Diseases, USA, CO, Fort Collins
Project summaryThe purpose of this project is to improve monitoring and control of zoonotic bacterial infections (plague, pseudotuberculosis, rickettsiosis, bartonellosis, brucellosis) of rodents and their ectoparasites (fleas, ticks) in South-West Tian-Shan and Pamir-Alai (Osh, Jalal-Abad and Batken region of Kyrgyzstan). Yersinia pestis (agent of plague), some Rickettsia spp. and Bartonella spp. are infectious agents carried by rodents and transmitted by fleas thus have some similarities in their lifestyle. Brucella was reported in rodents in Central Asia, but its identification is no longer possible due to the lack of appropriate expertise in the country. Yersinia pseudotuberculosis is closely related to the causative agent of plague (Y.pestis), which has also been found in rodents in Kyrgyzstan, but the relationship between these two species of Yersinia is unclear. Data obtained from the proposed project will be very important to the health authorities and other government agencies in Kyrgyzstan enabling them to detect (define) and promptly report cases and outbreaks of diseases (natural or intentionally delivered), and to provide a system that is sustainable by budget and infrastructure of Kyrgyzstan. From the public health perspective, it is important to know what kinds of animals are reservoirs and what kinds of ectoparasites are vectors for specific agents of infectious diseases.
Status of research. Kyrgyzstan is located in Central Asia. It is not well characterized by agents of zoonoses available, as compared to the same species found in Europe, North America and East Asia. As a result, their persity may occur both at genotypic and phenotypic level, compared with other parts of the world. For example, PCR, which determined the sequence specific to European and North American strains, may not recognize the strains from Central Asia, because their sequences differ. As a result, strains isolated in Kyrgyzstan should be tested to improve diagnosis by recognizing the differences found in the local strains. This project aims to develop and implement the screening method for unknown pathogens that may be present in the body of fleas.
More than 10 species of rodents (Marmota caudata, Dryomys nitedula, Cricetulus migratorius, Alticola argentatus, Microtus carruthersigalis, Microtus gregalis, Apodemus sylvaticus, Mus musculus, Rattusturkestanicus etc.) are found in southern Kyrgyzstan. This list of rodents was recently updated with the Norway rats (Rattus norvegicus), which invaded the territory of Kyrgyzstan from neighboring Uzbekistan and this species rapidly expands its area of distribution. There are reports demonstrating spread and increase of the rat population. Therefore, epizootic and epidemiological consequences of the invasion of rats should be investigated.
Plague is a re-emerging disease and is still a serious danger in the world, and the possibility of human outbreaks of plague in many parts of the world, including Kyrgyzstan, is increasing. The ability of Y.pestis to develop a resistance against antibiotics in natural environment is also a concern for public health. Rickettsial diseases are caused by a small obligate intracellular bacterium of the genus Rickettsia, and they are being distributed throughout the world. Our study will focus on R. typhi and R. felis, which are carried by rodents and transmitted by fleas, which are the causative agents of murine (endemic) typhus and old typhus of flea. Clinical symptoms of spotted fever and typhus in humans are very similar. This underlines importance of rapid diagnosis for specific pathogens, such as multiplex PCR. Bartonellos is caused by a small optional intracellular bacterium of the genus Bartonella (including B. elizabethae, B. grahamii, B.vinsonii, and B.henselae). Bartonella henselae is the causative agent of cat scratch fever, and at least 10 more species of Bartonella can cause human disease and are considered as the new pathogens to humans. Bartonella spp. has been studied in most regions of the world, but it remains unknown in Kyrgyzstan and other Central Asian countries.
Yersinia, Rickettsia and Bartonella primarily infect small mammals, which act as a reservoir where they spread agents from infected hosts to uninfected inpiduals by flea (and also by ticks in case of Rickettsia). Co-detection of Y. pestis and Bartonella species, both Gram-negative rods, has been found in ancient plague burial sites and detected in prairie dogs in the western US. Culture isolation and serological methods are commonly used to identify Y. pestis, Y. pseudotuberculosis, Bartonella, Brucella and Rickettsia spp., however we will focus on molecular diagnostics where these methods have been implemented for rapid detection of Yersinia, Bartonella, Brucella, and Rickettsia in rodents and fleas. PCR detection of plague and rickettsia pathogens, which is genetically strain specific, is a very sensitive method of detection and suitable for rapid identification of pathogens. However, in order to detect novel strains, PCR assays will need to be continually updated or sequencing done where amplification material from multiplex PCR can be used for sequencing. Culture isolation of pathogens will not be conducted, because a BSL-3 is not available.
Our justification and rationale for this project is summarized in the following points:
1. Use of modern molecular and biological methods of diagnosis of disease agents for more accurate, quicker, and sensitive diagnosis.
2. Collect field data for detection and identification of Y.pestis, Y. pseudotuberculosis, Bartonella, Brucella, and Rickettsia spp. among rodents and their ectoparasites in southwestern Tian-Shan and Pamir-Alai (Osh, Jalal-Abad and Batken region of Kyrgyzstan).
3. Determine the role of specific types of rodents and their ectoparasites in the spread of plague, pseudotuberculosis bartonellosis, brucellosis and rickettsiosis in southwestern Tian-Shan and Pamir-Alai and the development of prevention methods.
Impact of the proposed project on the progress in this area
This project allows institutions in Kyrgyzstan to participate in studies that will: 1) lead to the development of predictive models for coexistence of several rodent-borne bacterial diseases, which, in turn, allow implementation of appropriate prevention and control strategies; 2) describe the impact of mixed infections on epidemiology of zoonotic disease; and 3) design improved rapid techniques for detection and identification of multiple bacterial pathogens from animal samples.
Moreover, the project will provide to some Kyrgyz researchers, who previously worked on the State Ministry of Defense, the possibility to gain new experience and establish international connections for carrying out fundamental and applied studies within the framework of international science and technology programs for biology and medicine. Therefore, the proposal will allow Kyrgyz researchers to establish and conduct collaborative studies with other international scientific community.
Project team competences in the area. Project members have extensive experience conducting epidemiological surveys of plague, which is confirmed by publications in the area and participation in various international conferences. Bacteriologists have identified a large number of strains of the plague microbe. Bacteriologists, zoologists and bacteriology laboratory assistants attended and successfully completed training and professional development courses on diagnosis of plague in different anti-plague institutes of the CIS. Recent training courses attended were held at the Kazakh Science Center for Quarantine and Zoonotic Diseases named after M. Aikimbayev conducted with the support of ISTC Project K-1817.
Scientists of Zoology and Ecology Department at Osh State University have extensive experience in conducting field research. In recent years, they have carried out an inventory of fauna of specially protected natural areas in southern Kyrgyzstan.
Expected outcomes and their use. The project implementation will lead to a number of important outcomes:
- PCR diagnostics will be introduced for accurate, more rapid, and sensitive diagnostics of Y.pestis, Y. pseudotuberculosis, Bartonella, Brucella, and Rickettsia spp. in rodents and their ectoparasites in Kyrgyzstan.
- Will be created the electronic database and digital map to illustrate distribution of Y.pestis, Y. pseudotuberculosis, Bartonella, Brucella, and Rickettsia spp. in the southern region of Kyrgyzstan, to allow efficient monitoring and surveillance of these zoonosis.
- Will be identified the role of specific types of rodents and ectoparasites in distribution of certain zoonosis.
- Will be developed a series of measures to prevent plague, pseudotuberculosis bartonellosis, brucellosis and rickettsiosis in south-western Tian Shan and Pamir-Alai.
- Will be created a controlling system of zoonosis, which is sustainable by the budget and infrastructure of Kyrgyzstan.
- The risk of unpredictable epidemic complications on plague, pseudotuberculosis, bartonellosis, brucellosis and rickettsial disease in southwestern Tian-Shan and Pamir-Alai will be reduced.
- Will be provided opportunities for scientists and engineers to address scientific and technical challenges of epizootic survey and develop their knowledge and expertise in modern methods of laboratory diagnosis of plague.
Relevance of the project to objectives of the ISTC. The proposed project is consistent with the objectives of the ISTC, as it is aimed at applied research and contributes to the solution of national and international issues related to countering biological threats. Also, compliance with these objectives is achieved through the planned involvement of scientists from the participating organizations in the world scientific community by providing information on the project at international conferences and seminars.