Michael Kosoy - Academia.edu (original) (raw)
Papers by Michael Kosoy
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Background/Question/Methods A central question in disease ecology is how pathogen diversity is ge... more Background/Question/Methods A central question in disease ecology is how pathogen diversity is generated and maintained in host populations and its influence on disease dynamics. We use Bartonella in African fruit bats to explore how host population structure supports high pathogen diversity and infection prevalence. Bartonella are facultative intracellular bacteria that infect a variety of mammals worldwide, showing particularly high prevalence and diversity in bats. Bartonella species are transmitted by hematophagous arthropods and it is hypothesized that ectoparasitic bat flies are vectors of the bacteria in bats. However, little is known about how bat and bat fly ecology contribute to Bartonella transmission dynamics. Recent studies show that the fruit bat Eidolon helvum is panmictic across its African range. We hypothesize that this level of connectivity allows for high transmission of Bartonella among distant populations, resulting in minimal population structure and high dive...
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Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused ... more Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused by a ratborne Bar-tonella strain related B. tribocorum and B. elizabethae. The finding suggests that this Bartonella strain could be spread by infected rats and represents a potential human risk.
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From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genu... more From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genus Rattus is exceptional. The review analyzes specific characteristics of rats that contribute to their important role in hosting pathogens, such as host–pathogen relations and rates of rat-borne infections, taxonomy, ecology, and essential factors. Specifically the review addresses recent taxonomic revisions within the genus Rattus that resulted from applications of new genetic tools in understanding relationships between the Old World rats and the infectious agents that they carry. Among the numerous species within the genus Rattus, only three species—the Norway rat (R. norvegicus), the black or roof rat (R. rattus), and the Asian black rat (R. tanezumi)—have colonized urban ecosystems globally for a historically long period of time. The fourth invasive species, R. exulans, is limited to tropical Asia–Pacific areas. One of the points highlighted in this review is the necessity to discriminate the roles played by rats as pathogen reservoirs within the land of their original diversification and in regions where only one or few rat species were introduced during the recent human history.
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Infectious agents, their hosts, and relevant abiotic components are directly involved in the comp... more Infectious agents, their hosts, and relevant abiotic components are directly involved in the complex dynamic process of maintaining infectious diseases in Nature. The current tendency to focus on host-pathogen interactions at the molecular and organismal levels does not advance our knowledge about infectious diseases, as much as it potentially could, by ignoring the ecological context pivotal for understanding the biology of the diseases. A new model of investigation requires a dynamic shift of perspectives in the " simplicity-complexity " dimension: from virulence factors to multi-sided descriptions of the pathogens; from particular microbes to wide microbial communities; from clinical manifestations to a variety of infectious patterns; from findings of infectious agents to defining a natural focus of the infection as a self-regulated system; from single factors affecting host-parasite relations to the complex ecological context. Various aspects of interactions between hosts, vectors, pathogens, and environmental niches should be integrated at multiple spatiotemporal scales and at different levels of biological organization (molecular, genomic, organismal, population, and ecosystem).
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The presence of bartonellae in invasive rats (Rattus rattus) and indigenous rodents (Arvicanthis ... more The presence of bartonellae in invasive rats (Rattus rattus) and indigenous rodents (Arvicanthis niloticus and Cricetomys gambianus) from two districts in Uganda, Arua and Zombo, was examined by PCR detection and culture. Blood from a total of 228 R. rattus, 31 A. niloticus, and 5 C. gambianus was screened using genus-specific primers targeting the 16S–23S intergenic spacer region. Furthermore, rodent blood was plated on brain heart infusion blood agar, and isolates were verified as Bartonella species using citrate synthase gene-(gltA) specific primers. One hundred and four fleas recovered from R. rattus were also tested for the presence of Bartonella species using the same gltA primer set. An overall prevalence of 1.3% (three of 228) was obtained in R. rattus, whereas 61.3% of 31 A. niloticus and 60% of five C. gambianus were positive for the presence of Bartonella species. Genotypes related to Bartonella elizabethae, a known zoonotic pathogen, were detected in three R. rattus and one C. gambianus. Bartonella strains, similar to bacteria detected in indigenous rodents from other African countries, were isolated from the blood of A. niloticus. Bartonellae, similar to bacteria initially cultured from Ornithodorus sonrai (soft tick) from Senegal, were found in two C. gambianus. Interestingly, bartonellae detected in fleas from invasive rats were similar to bacteria identified in indigenous rodents and not their rat hosts, with an overall prevalence of 6.7%. These results suggest that if fleas are competent vectors of these bartonellae, humans residing in these two districts of Uganda are potentially at greater risk for exposure to Bartonella species from native rodents than from invasive rats. The low prevalence of bartonellae in R. rattus was quite surprising, in contrast, to the detection of these organisms in a large percentage of Rattus species from other geographical areas. A possible reason for this disparity is discussed.
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PLOS ONE, 2015
Our study highlights the surveillance of Bartonella species among rodents and their associated ec... more Our study highlights the surveillance of Bartonella species among rodents and their associated ectoparasites (ticks, fleas, lice, and mites) in several regions across Thailand. A total of 619 rodents and 554 pooled ectoparasites (287 mite pools, 62 flea pools, 35 louse pools, and 170 tick pools) were collected from 8 provinces within 4 regions of Thailand. Bandicota indica (279), Rattus rattus (163), and R. exulans (96) were the most prevalent species of rats collected in this study. Real-time PCR assay targeting Bartonella-specific ssrA gene was used for screening and each positive sample was confirmed by PCR using nuoG gene. The prevalence of Bartonella DNA in rodent (around 17%) was recorded in all regions. The highest prevalence of Bartonella species was found in B. savilei and R. rattus with the rate of 35.7% (5/14) and 32.5% (53/163), respectively. High prevalence of Bartonella-positive rodent was also found in B. indica (15.1%, 42/279), and R. norvegicus (12.5%, 5/40). In contrast, the prevalence of Bartonella species in ectoparasites collected from the rats varied significantly according to types of ectoparasites. A high prevalence of Bartonella DNA was found in louse pools (Polyplax spp. and Hoplopleura spp., 57.1%) and flea pools (Xenopsylla cheopis, 25.8%), while a low prevalence was found in pools of mites (Leptotrombidium spp. and Ascoschoengastia spp., 1.7%) and ticks (Haemaphysalis spp., 3.5%). Prevalence of Bartonella DNA in ectoparasites collected from Bartonella-positive rodents (19.4%) was significantly higher comparing to ectoparasites from Bartonella-negative rodents (8.7%). The phylogenetic analysis of 41 gltA sequences of 16 Bartonella isolates from rodent blood and 25 Bartonella-positive ectoparasites revealed a wide range of diversity among Bartonella species with a majority of sequences (61.0%) belonging to Bartonella elizabethae complex (11 rodents, 1 mite pool, and 5 louse pools), while the remaining sequences were identical to B. phoceensis (17.1%, 1 mite pool, 5 louse pools, and 1 tick pool), B. coopersplainensis (19.5%, 5 rodents, 1 louse pool, and 2 tick pools), and one previously unidentified Bartonella species (2.4%, 1 louse pool).
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Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused ... more Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused by a ratborne Bar-tonella strain related B. tribocorum and B. elizabethae. The finding suggests that this Bartonella strain could be spread by infected rats and represents a potential human risk.
Bookmarks Related papers MentionsView impact
American Journal of Tropical Medicine and Hygiene, 2011
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Voprosy virusologii
The employment of two serological tests (indirect fluorescence antibody technique and neutralizat... more The employment of two serological tests (indirect fluorescence antibody technique and neutralization test) demonstrated the leading role of Hantaan virus serotype 1 strains isolated from field mice in the pattern of the incidence of hemorrhagic fever with renal syndrome (HFRS). Proofs of the etiological importance of strains of serotypes 3 and 5 occurring in brown rats and Cl. rufocanus were obtained. No data on any association of human HFRS cases with strains of serotype 4 isolated from reed voles could be demonstrated.
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Zhurnal mikrobiologii, epidemiologii, i immunobiologii
The use of the serological method (the indirect fluorescent antibody test) for the examination of... more The use of the serological method (the indirect fluorescent antibody test) for the examination of 255 persons coming in contact with patients having hemorrhagic fever with the renal syndrome (HFRS) in the foci of this infection where outbreaks of group infection had been registered made it possible to detect mild, unclear and asymptomatic forms of HFRS in 17.7-20.9% of cases. The simultaneous titration of 317 serum samples with two antigens revealed that HFRS virus of serotype 1, similar to strain Hantaan from Korea, may cause, besides the classical forms of the disease, the development of mild and asymptomatic forms of this infection.
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Bookmarks Related papers MentionsView impact
Voprosy virusologii
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The American journal of tropical medicine and hygiene
The objectives of this study were to extend our knowledge of the geographic distribution and rode... more The objectives of this study were to extend our knowledge of the geographic distribution and rodent host range of arenaviruses in North America. Sera from wild rodents collected from the southern and western United States were tested for antibody against Tamiami, Pichinde, Junin, and lymphocytic choriomeningitis viruses, using an indirect fluorescent antibody test. Antibody to at least one arenavirus was found in 220 (3.1%) of 7,106 rodents tested. The antibody-positive animals included Mus musculus from Florida and Texas; Neotoma albigula from Arizona, Colorado, and New Mexico; N. fuscipes and N. lepida from California: N. mexicana from Arizona, New Mexico, and Utah; N. stephensi from Arizona and New Mexico; and Oryzomys palustris and Sigmodon hispidus from Florida. Sigmodon hispidus seropositive for Tamiami virus were found only in Florida (156 [27.0%] of 578 tested), although 463 hispid cotton rats from outside that state were examined. High-titered antibodies to Tamiami virus were present in sera from S. hispidus, (geometric mean antibody titer [GMAT] of 1:792), whereas sera from Neotoma spp. reacted at high titer to both Tamiami (GMAT = 1:905) and Pichinde (GMAT = 1:433) viruses. The results suggest that arenaviruses are widely distributed in the southern United States and that one or more indigenous arenaviruses are associated with Neotoma spp. in North America.
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Zhurnal mikrobiologii, epidemiologii, i immunobiologii
The sporadic character of the occurrence of hemorrhagic fever with the renal syndrome in the Prim... more The sporadic character of the occurrence of hemorrhagic fever with the renal syndrome in the Primorye Territory has been established. Three rodent species have been found to be spontaneously infected with the causative agent of this disease. Antibodies in patients with this disease are detected at its early stages and persist for a long time after convalescence. The possibility of the formation of a contingent immune to hemorrhagic fever, due to the persons who have had mild and asymptomatic forms of this infection has been shown.
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Voprosy virusologii
Examinations of 6362 small mammals of 18 species revealed the main reservoirs of the causative ag... more Examinations of 6362 small mammals of 18 species revealed the main reservoirs of the causative agent of hemorrhagic fever with the renal syndrome (HFRS) in foci of the Primorsky Krai, and demonstrated the importance of individual species in the epidemiology of the infection. Data on the circulation in the region of antigenically different serotypes of HFRS virus are presented.
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Bookmarks Related papers MentionsView impact
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Background/Question/Methods A central question in disease ecology is how pathogen diversity is ge... more Background/Question/Methods A central question in disease ecology is how pathogen diversity is generated and maintained in host populations and its influence on disease dynamics. We use Bartonella in African fruit bats to explore how host population structure supports high pathogen diversity and infection prevalence. Bartonella are facultative intracellular bacteria that infect a variety of mammals worldwide, showing particularly high prevalence and diversity in bats. Bartonella species are transmitted by hematophagous arthropods and it is hypothesized that ectoparasitic bat flies are vectors of the bacteria in bats. However, little is known about how bat and bat fly ecology contribute to Bartonella transmission dynamics. Recent studies show that the fruit bat Eidolon helvum is panmictic across its African range. We hypothesize that this level of connectivity allows for high transmission of Bartonella among distant populations, resulting in minimal population structure and high dive...
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Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused ... more Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused by a ratborne Bar-tonella strain related B. tribocorum and B. elizabethae. The finding suggests that this Bartonella strain could be spread by infected rats and represents a potential human risk.
Bookmarks Related papers MentionsView impact
From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genu... more From the perspective of ecology of zoonotic pathogens, the role of the Old World rats of the genus Rattus is exceptional. The review analyzes specific characteristics of rats that contribute to their important role in hosting pathogens, such as host–pathogen relations and rates of rat-borne infections, taxonomy, ecology, and essential factors. Specifically the review addresses recent taxonomic revisions within the genus Rattus that resulted from applications of new genetic tools in understanding relationships between the Old World rats and the infectious agents that they carry. Among the numerous species within the genus Rattus, only three species—the Norway rat (R. norvegicus), the black or roof rat (R. rattus), and the Asian black rat (R. tanezumi)—have colonized urban ecosystems globally for a historically long period of time. The fourth invasive species, R. exulans, is limited to tropical Asia–Pacific areas. One of the points highlighted in this review is the necessity to discriminate the roles played by rats as pathogen reservoirs within the land of their original diversification and in regions where only one or few rat species were introduced during the recent human history.
Bookmarks Related papers MentionsView impact
Infectious agents, their hosts, and relevant abiotic components are directly involved in the comp... more Infectious agents, their hosts, and relevant abiotic components are directly involved in the complex dynamic process of maintaining infectious diseases in Nature. The current tendency to focus on host-pathogen interactions at the molecular and organismal levels does not advance our knowledge about infectious diseases, as much as it potentially could, by ignoring the ecological context pivotal for understanding the biology of the diseases. A new model of investigation requires a dynamic shift of perspectives in the " simplicity-complexity " dimension: from virulence factors to multi-sided descriptions of the pathogens; from particular microbes to wide microbial communities; from clinical manifestations to a variety of infectious patterns; from findings of infectious agents to defining a natural focus of the infection as a self-regulated system; from single factors affecting host-parasite relations to the complex ecological context. Various aspects of interactions between hosts, vectors, pathogens, and environmental niches should be integrated at multiple spatiotemporal scales and at different levels of biological organization (molecular, genomic, organismal, population, and ecosystem).
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The presence of bartonellae in invasive rats (Rattus rattus) and indigenous rodents (Arvicanthis ... more The presence of bartonellae in invasive rats (Rattus rattus) and indigenous rodents (Arvicanthis niloticus and Cricetomys gambianus) from two districts in Uganda, Arua and Zombo, was examined by PCR detection and culture. Blood from a total of 228 R. rattus, 31 A. niloticus, and 5 C. gambianus was screened using genus-specific primers targeting the 16S–23S intergenic spacer region. Furthermore, rodent blood was plated on brain heart infusion blood agar, and isolates were verified as Bartonella species using citrate synthase gene-(gltA) specific primers. One hundred and four fleas recovered from R. rattus were also tested for the presence of Bartonella species using the same gltA primer set. An overall prevalence of 1.3% (three of 228) was obtained in R. rattus, whereas 61.3% of 31 A. niloticus and 60% of five C. gambianus were positive for the presence of Bartonella species. Genotypes related to Bartonella elizabethae, a known zoonotic pathogen, were detected in three R. rattus and one C. gambianus. Bartonella strains, similar to bacteria detected in indigenous rodents from other African countries, were isolated from the blood of A. niloticus. Bartonellae, similar to bacteria initially cultured from Ornithodorus sonrai (soft tick) from Senegal, were found in two C. gambianus. Interestingly, bartonellae detected in fleas from invasive rats were similar to bacteria identified in indigenous rodents and not their rat hosts, with an overall prevalence of 6.7%. These results suggest that if fleas are competent vectors of these bartonellae, humans residing in these two districts of Uganda are potentially at greater risk for exposure to Bartonella species from native rodents than from invasive rats. The low prevalence of bartonellae in R. rattus was quite surprising, in contrast, to the detection of these organisms in a large percentage of Rattus species from other geographical areas. A possible reason for this disparity is discussed.
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PLOS ONE, 2015
Our study highlights the surveillance of Bartonella species among rodents and their associated ec... more Our study highlights the surveillance of Bartonella species among rodents and their associated ectoparasites (ticks, fleas, lice, and mites) in several regions across Thailand. A total of 619 rodents and 554 pooled ectoparasites (287 mite pools, 62 flea pools, 35 louse pools, and 170 tick pools) were collected from 8 provinces within 4 regions of Thailand. Bandicota indica (279), Rattus rattus (163), and R. exulans (96) were the most prevalent species of rats collected in this study. Real-time PCR assay targeting Bartonella-specific ssrA gene was used for screening and each positive sample was confirmed by PCR using nuoG gene. The prevalence of Bartonella DNA in rodent (around 17%) was recorded in all regions. The highest prevalence of Bartonella species was found in B. savilei and R. rattus with the rate of 35.7% (5/14) and 32.5% (53/163), respectively. High prevalence of Bartonella-positive rodent was also found in B. indica (15.1%, 42/279), and R. norvegicus (12.5%, 5/40). In contrast, the prevalence of Bartonella species in ectoparasites collected from the rats varied significantly according to types of ectoparasites. A high prevalence of Bartonella DNA was found in louse pools (Polyplax spp. and Hoplopleura spp., 57.1%) and flea pools (Xenopsylla cheopis, 25.8%), while a low prevalence was found in pools of mites (Leptotrombidium spp. and Ascoschoengastia spp., 1.7%) and ticks (Haemaphysalis spp., 3.5%). Prevalence of Bartonella DNA in ectoparasites collected from Bartonella-positive rodents (19.4%) was significantly higher comparing to ectoparasites from Bartonella-negative rodents (8.7%). The phylogenetic analysis of 41 gltA sequences of 16 Bartonella isolates from rodent blood and 25 Bartonella-positive ectoparasites revealed a wide range of diversity among Bartonella species with a majority of sequences (61.0%) belonging to Bartonella elizabethae complex (11 rodents, 1 mite pool, and 5 louse pools), while the remaining sequences were identical to B. phoceensis (17.1%, 1 mite pool, 5 louse pools, and 1 tick pool), B. coopersplainensis (19.5%, 5 rodents, 1 louse pool, and 2 tick pools), and one previously unidentified Bartonella species (2.4%, 1 louse pool).
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Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused ... more Lymphadenopathy and fever that developed in a woman in Tbilisi, Georgia, most likely were caused by a ratborne Bar-tonella strain related B. tribocorum and B. elizabethae. The finding suggests that this Bartonella strain could be spread by infected rats and represents a potential human risk.
Bookmarks Related papers MentionsView impact
American Journal of Tropical Medicine and Hygiene, 2011
Bookmarks Related papers MentionsView impact
Voprosy virusologii
The employment of two serological tests (indirect fluorescence antibody technique and neutralizat... more The employment of two serological tests (indirect fluorescence antibody technique and neutralization test) demonstrated the leading role of Hantaan virus serotype 1 strains isolated from field mice in the pattern of the incidence of hemorrhagic fever with renal syndrome (HFRS). Proofs of the etiological importance of strains of serotypes 3 and 5 occurring in brown rats and Cl. rufocanus were obtained. No data on any association of human HFRS cases with strains of serotype 4 isolated from reed voles could be demonstrated.
Bookmarks Related papers MentionsView impact
Zhurnal mikrobiologii, epidemiologii, i immunobiologii
The use of the serological method (the indirect fluorescent antibody test) for the examination of... more The use of the serological method (the indirect fluorescent antibody test) for the examination of 255 persons coming in contact with patients having hemorrhagic fever with the renal syndrome (HFRS) in the foci of this infection where outbreaks of group infection had been registered made it possible to detect mild, unclear and asymptomatic forms of HFRS in 17.7-20.9% of cases. The simultaneous titration of 317 serum samples with two antigens revealed that HFRS virus of serotype 1, similar to strain Hantaan from Korea, may cause, besides the classical forms of the disease, the development of mild and asymptomatic forms of this infection.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Voprosy virusologii
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Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
The American journal of tropical medicine and hygiene
The objectives of this study were to extend our knowledge of the geographic distribution and rode... more The objectives of this study were to extend our knowledge of the geographic distribution and rodent host range of arenaviruses in North America. Sera from wild rodents collected from the southern and western United States were tested for antibody against Tamiami, Pichinde, Junin, and lymphocytic choriomeningitis viruses, using an indirect fluorescent antibody test. Antibody to at least one arenavirus was found in 220 (3.1%) of 7,106 rodents tested. The antibody-positive animals included Mus musculus from Florida and Texas; Neotoma albigula from Arizona, Colorado, and New Mexico; N. fuscipes and N. lepida from California: N. mexicana from Arizona, New Mexico, and Utah; N. stephensi from Arizona and New Mexico; and Oryzomys palustris and Sigmodon hispidus from Florida. Sigmodon hispidus seropositive for Tamiami virus were found only in Florida (156 [27.0%] of 578 tested), although 463 hispid cotton rats from outside that state were examined. High-titered antibodies to Tamiami virus were present in sera from S. hispidus, (geometric mean antibody titer [GMAT] of 1:792), whereas sera from Neotoma spp. reacted at high titer to both Tamiami (GMAT = 1:905) and Pichinde (GMAT = 1:433) viruses. The results suggest that arenaviruses are widely distributed in the southern United States and that one or more indigenous arenaviruses are associated with Neotoma spp. in North America.
Bookmarks Related papers MentionsView impact
Zhurnal mikrobiologii, epidemiologii, i immunobiologii
The sporadic character of the occurrence of hemorrhagic fever with the renal syndrome in the Prim... more The sporadic character of the occurrence of hemorrhagic fever with the renal syndrome in the Primorye Territory has been established. Three rodent species have been found to be spontaneously infected with the causative agent of this disease. Antibodies in patients with this disease are detected at its early stages and persist for a long time after convalescence. The possibility of the formation of a contingent immune to hemorrhagic fever, due to the persons who have had mild and asymptomatic forms of this infection has been shown.
Bookmarks Related papers MentionsView impact
Voprosy virusologii
Examinations of 6362 small mammals of 18 species revealed the main reservoirs of the causative ag... more Examinations of 6362 small mammals of 18 species revealed the main reservoirs of the causative agent of hemorrhagic fever with the renal syndrome (HFRS) in foci of the Primorsky Krai, and demonstrated the importance of individual species in the epidemiology of the infection. Data on the circulation in the region of antigenically different serotypes of HFRS virus are presented.
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Bookmarks Related papers MentionsView impact
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