Haemoplasmas in wild rodents: Routes of transmission and infection dynamics

Molecular Detection and Characterization of Hemotropic Mycoplasma in Assamese Macaques (Macaca assamensis) of Northern Thailand

Hemotropic mycoplasmas, also known as hemoplasmas, are parasitic bacteria that infect red blood cells, potentially leading to varying degrees of anemia across numerous mammalian species, including nonhuman primates. The present study aims to investigate the prevalence of hemoplasma infection and identify the species involved among free-ranging Assamese macaques (Macaca assamensis) inhabiting northern Thailand. A total of 133 blood samples were collected from Assamese macaques in Chiang Rai province, Thailand, and subjected to screening for hemoplasma infection utilizing nested PCR amplification targeting the 16S rRNA gene. Positive samples were subsequently analyzed through nucleotide sequencing and phylogenetic analysis for putative species identification. Current study results revealed that 17.3% (23/133; 95% CI 11.29-24.81) of Assamese macaques tested positive for hemoplasma infection using the nested PCR assay. Partial 16S rRNA sequences derived from hemoplasma isolates in Assamese macaques exhibited 99% homology, forming a cluster within the same phylogenetic clade as "Candidatus Mycoplasma haematomacacae," previously identified in long-tailed macaques, rhesus macaques, and Japanese macaques. These findings suggest the presence of "Ca. M. haematomacacae" not only in long-tailed macaques and rhesus macaques but also in Assamese macaques in Thailand. To our knowledge, this marks the first molecular detection of "Ca. M. haematomacacae" in Assamese macaques in Thailand. These results hold significance as they enhance our understanding of hemoplasma infection distribution among macaque populations in Thailand.

High diversity, novel genotypes, and vertical transmission of hemotropic Mycoplasma in micromammals

Hemotropic mycoplasmas (hemoplasmas) are emerging zoonotic pathogens. Micromammals have received little attention as hosts for hemoplasmas despite their ubiquitous presence, high population abundances, and close association with humans. A PCR protocol targeting a fragment of the 16 S rRNA gene and direct sequencing in blood samples of 189 adult specimens and 35 fetuses belonging to three species of Eulipotyphla (shrews) and seven species of Rodentia, captured in three ecologically diverse habitats in North-Eastern Spain (Steppe, High Mountain, Mediterranean) yielded and occurrence of 26%, including 36% of 39 shrews and 23% of 150 rodents. Sequencing revealed the presence of 14 nucleotide sequence types (ntST) among the 56 readable sequences. In general, each ntST was associated with a given host species, although in some cases, the same ntST was sequenced in different species (chiefly rodents). Most ntST were closely related to rodent and/or bat hemoplasmas, but one was identical with Mycoplasma haemocanis/haemofelis, and others can be considered novel genotypes. High sequence diversity was detected in rodents, whereas in the white-toothed shrew (Crocidura russula), 9/11 sequences from two distant areas were identical. Phylogenetic and network analyses classified our sequences in different clades including hemoplasmas of rodents, carnivores, bats, and humans. Twelve of the fetuses (34.2%) of 9/12 litters (75.0%) of shrews and rodents were hemoplasma-positive, indicating frequent vertical transmission. Our study contributes to expanding our knowledge about the distribution, diversity, and transmission of hemoplasmas.

Hemotropic Mycoplasmas (Hemoplasmas) in Free-Ranging Azara's Agoutis (Dasyprocta azarae) from an Urban Area of Southern Brazil

Hemotropic mycoplasmas (hemoplasmas) are opportunistic bacteria that attach to the erythrocyte surface, causing infectious anemia in several mammalian species, including rodents. Studies surveying native Azara's agoutis (Dasyprocta azarae) in Brazil are lacking. Accordingly, the present study aimed to assess hemoplasmas infection in free-ranging agoutis from an urban environmental conservation area in Curitiba, southern Brazil. Overall, 11/35 (31.43%) agoutis were positive to hemoplasmas by quantitative PCR (cycle threshold≤34.4). Sequencing of the 16S ribosomal RNA gene indicated Mycoplasma haemomuris infection, closely related to M. haemomuris subsp. ratti, suggesting hemoplasma transmission from urban rats to agoutis. Because the main route of M. haemomuris transmission has been direct rodent-to-rodent infection, the relatively lower positivity that we detected may be the result of low intraspecies contact due to the smaller social units of agoutis, generally consisting of two to four individuals, and low interspecies contact due to only sporadic agouti-rat interactions in urban settings, compared with other rodent species interactions. Further studies should be conducted to determine whether the hemoplasma infection that we found can cause clinical onset and life-threatening anemia in agoutis.

Bat cellular immunity varies by year and dietary habit amidst land conversion

Monitoring the health of wildlife populations is essential in the face of increased agricultural expansion and forest fragmentation. Loss of habitat and habitat degradation can negatively affect an animal's physiological state, possibly resulting in immunosuppression and increased morbidity or mortality. We sought to determine how land conversion may differentially impact cellular immunity and infection risk in Neotropical bats species regularly infected with bloodborne pathogens, and to evaluate how effects may vary over time and by dietary habit. We studied common vampire bats (Desmodus rotundus), northern yellow-shouldered bats (Sturnira parvidens) and Mesoamerican mustached bats (Pteronotus mesoamericanus), representing the dietary habits of sanguivory, frugivory and insectivory respectively, in northern Belize. We compared estimated total white blood cell count, leukocyte differentials, neutrophil to lymphocyte ratio and infection status with two bloodborne bacterial pathogens (Bartonella spp. and hemoplasmas) of 118 bats captured in a broadleaf, secondary forest over three years (2017-2019). During this period, tree cover decreased by 14.5% while rangeland expanded by 14.3%, indicating increasing habitat loss and fragmentation. We found evidence for bat species-specific responses of cellular immunity between years, with neutrophil counts significantly decreasing in S. parvidens from 2017 to 2018, but marginally increasing in D. rotundus. However, the odds of infection with Bartonella spp. and hemoplasmas between 2017 and 2019 did not differ between bat species, contrary to our prediction that pathogen prevalence may increase with land conversion. We conclude that each bat species invested differently in cellular immunity in ways that changed over years of increasing habitat loss and fragmentation. We recommend further research on the interactions between land conversion, immunity and infection across dietary habits of Neotropical bats for informed management and conservation.

Molecular detection and characterization of vector-borne agents in common opossums (Didelphis marsupialis) from northeastern Brazil

Opossums are synanthropic marsupials able to interchange among wild, peri-urban and urban environments, playing an epidemiologically important role as hosts for emerging pathogens and ectoparasites of relevance in public health. The present study aimed to detect and molecularly characterize vector-borne agents in a population of common opossums (Didelphis marsupialis) from the Island of São Luís do Maranhão, northeastern Brazil. Of the 45 animals analyzed, one (2.22%) was positive in the nested PCR assay based on the 18S rRNA gene of piroplasmids. The obtained sequence was phylogenetically positioned in a clade containing sequences of Babesia sp. previously detected in Didelphis aurita, Didelphis albiventris and associated ticks from Brazil. Eight (17.77%) samples were positive in PCR for Ehrlichia spp. based on the dsb gene; four samples were sequenced and positioned into a new clade, sister to E. minasensis and Ehrlichia sp. clade detected in Superorder Xenarthra mammals. No samples tested positive in the screening PCR assays based on the 16S rRNA gene of Anaplasma spp. Two samples were positive in the qPCR for Bartonella spp. based on the nuoG gene. Seven animals (15.56%) were positive in the nPCR based on the 16S rRNA gene of hemoplasmas. Of these, three were positive in a PCR based on the 23S rRNA gene. The phylogenies based on both 16S rRNA and 23S rRNA genes corroborated to each other and positioned the sequences in the same clade of hemoplasmas previously detected in D. aurita and D. albiventris sampled in Brazil. Finally, three (6.66%) animals were positive in the PCR for Hepatozoon spp.; the obtained 18S rRNA sequence was positioned into the H. felis clade.The present study showed, for the first time, the circulation of piroplasmids, Hepatozoon spp., Ehrlichia spp., hemoplasmas and Bartonella spp. in D. marsupialis sampled in northeastern Brazil, with description of putative novel genotypes of Ehrlichia and Hepatozoon and copositivity by different vector-borne agents. The present work consolidates the "South American Marsupialia" piroplasmid clade, adding one more genotype of Babesia sp. to this clade.

Molecular Survey of Hemotropic Mycoplasma spp. and Bartonella spp. in Coatis (Nasua nasua) from Central-Western Brazil

Even though previous works showed molecular evidence of hemotropic Mycoplasma spp. (hemoplasmas) in ring-tailed coatis (Nasua nasua) from Brazil, Bartonella sp. has not been reported in these mammals so far. The present study aimed to detect the above-mentioned agents in coatis’ blood and associated ectoparasites, assessing the association between these infections and red blood parameters. Between March 2018 and January 2019, coati (n = 97) blood samples, Amblyomma sp. ticks (2242 individual ticks, resulting in 265 pools), and Neotrichodectes pallidus louse (n = 59) were collected in forested urban areas from midwestern Brazil. DNA extracted from coatis’ blood, and ectoparasite samples were submitted to quantitative PCR (qPCR) (16S rRNA) and conventional PCR (cPCR) (16S rRNA and 23S rRNA) for hemoplasmas and qPCR (nuoG gene) and culturing (only blood) for Bartonella spp. Two different hemoplasma genotypes were detected in blood samples: 71% coatis positive for myc1 and 17% positive for myc2. While 10% of ticks were positive for hemoplasmas (myc1), no louse was positive. The estimated bacterial load of hemoplasmas showed no association with anemia indicators. All coatis were negative for Bartonella sp. in qPCR assay and culturing, albeit two Amblyomma sp. larvae pools, and 2 A. dubitatum nymph pools were positive in the qPCR. The present work showed a high occurrence of hemoplasmas, with two distinct hemoplasma genotypes, in coatis from forested urban areas in midwestern Brazil.

High prevalence and genetic diversity of hemoplasmas in bats and bat ectoparasites from China

Hemoplasmas can cause severe hemolytic anemia in humans. To explore the genetic diversity and the potential transmission routes of hemoplasmas among bat population, bats and bat-ectoparasites including bat-flies, bat-mites, and bat-ticks were collected in Eastern and Central China from 2015 to 2021, and tested with PCR for hemoplasmas 16S rRNA gene. Based on 16S rRNA PCR, 18.0% (103/572) adult bats were positive for hemoplasmas, but none of 11 fetuses from hemoplasmas-positive pregnant bats was positive for hemoplasmas. These results indicated that adult bats had a high prevalence of hemoplasma, but vertical transmission of hemoplasmas did not occurr in the bats. Based on the 16S rRNA gene PCR, the minimum infection rate of bat-ectoparasite for hemoplasmas was 4.0% (27/676), suggesting that bat-ectoparasite also had a high prevalence for hemoplasmas. Phylogenetic analysis revealed that bat hemoplasmas from this study clustered into 4 genotypes (I-IV). Genotype I clustered together with hemoplasmas identified in bats from America. Genotype II shared high similarity with a human-pathogenic hemoplasma Candidatus Mycoplasma haemohominis. Genotype III and IV were unique, representing 2 new hemoplasma genotypes. Only genotype I was identified in both bats and all bat-ectoparasites including bat-flies, bat-mites, and bat-ticks. In conclusion, bats and bat-ectoparasites from China harbored abundant genetically diverse hemoplasmas including potential human-pathogenic hemoplasmas, indicating bats and bat-ectoparasites may play important roles in the maintenance and transmission of hemoplasmas in the natural foci.

Co-infection by multiple vector-borne agents in wild ring-tailed coatis (Nasua nasua) from Iguaçu National Park, southern Brazil

The present study aimed to detect molecularly the presence of co-infections by vector-borne agents (VBA) in ring-tailed coatis' (Nasua nasua) blood samples from Iguaçu National Park (INP), southern Brazil, and assess the phylogenetic positioning of the detected agents. DNA blood samples were submitted to molecular screening and characterization for Anaplasmataceae agents, Piroplasmids, Hepatozoon sp., hemotropic mycoplasmas, and Bartonella spp. In total, 42 (85.7%) coatis were positive for hemotropic Mycoplasma sp., 12 (24.5%) for Bartonella machadoae, 7 (14.3%) for Anaplasma sp. closely related to 'Candidatus Anaplasma brasiliensis', and 3 (6%) for Hepatozoon procyonis. The most prevalent co-infections observed was from bacterial VBA: while 18.3% were co-infected by hemotropic Mycoplasma sp. and Bartonella sp., 12.2% were co-infected by Anaplasma sp. and hemotropic Mycoplasma sp. Only two animals (4%) presented co-infections by three VBA (Bartonella sp., Anaplasma sp. and hemotropic Mycoplasma sp.). The coati is a wild carnivore found in INP, mainly in areas visited by tourists. These animals are frequently seen searching for food in garbage dumps or in tourists' belongings. The present study expands the host specificity range of B. machadoae, which has been isolated only from rodents until the present moment. Since the zoonotic potential and transmission routes of the detected VBA are not yet known, surveillance in this area is much needed.

Multilayer Networks Assisting to Untangle Direct and Indirect Pathogen Transmission in Bats

The importance of species that connect the different types of interactions is becoming increasingly recognized, and this role may be related to specific attributes of these species. Multilayer networks have two or more layers, which represent different types of interactions, for example, between different parasites and hosts that are nonetheless connected. The understanding of the ecological relationship between bats, ectoparasites, and vector-borne bacteria could shed some light on the complex transmission cycles of these pathogens. In this study, we investigated a multilayer network in Brazil formed by interactions between bat-bacteria, bat-ectoparasite, and ectoparasite-bacteria, and asked how these interactions overlap considering different groups and transmission modes. The multilayer network was composed of 31 nodes (12 bat species, 14 ectoparasite species, and five bacteria genera) and 334 links, distributed over three layers. The multilayer network has low modularity and shows a core-periphery organization, that is, composed of a few generalist species with many interactions and many specialist species participating in few interactions in the multilayer network. The three layers were needed to accurately describe the multilayer structure, while aggregation leads to loss of information. Our findings also demonstrated that the multilayer network is influenced by a specific set of species that can easily be connected to the behavior, life cycle, and type of existing interactions of these species. Four bat species (Artibeus lituratus, A. planirostris, Phyllostomus discolor, and Platyrrhinus lineatus), one ectoparasite species (Steatonyssus) and three bacteria genera (Ehrlichia, hemotropic Mycoplasma and Neorickettsia) are the most important species for the multilayer network structure. Finally, our study brings an ecological perspective under a multilayer network approach on the interactions between bats, ectoparasites, and pathogens. By using a multilayer approach (different types of interactions), it was possible to better understand these different ecological interactions and how they affect each other, advancing our knowledge on the role of bats and ectoparasites as potential pathogen vectors and reservoirs, as well as the modes of transmission of these pathogens.

First Report of ‘Candidatus Mycoplasma haematomacacae’ in Laboratory-Kept Rhesus Monkeys (Macaca mulatta) Maintained in Rio de Janeiro, Brazil

Simple Summary

Health assessment in animals used in research studies are essential, since only animals that present no diseases are considered suitable for these purposes. In laboratory kept animals, a bacterium that infects red blood cells, named hemotropic Mycoplasma (also called hemoplasmas), has been described as problem for research studies. Different hemoplasma species have been detected infecting monkeys from Brazil. However, the occurrence of these bacteria in monkeys maintained in laboratory in Brazil have never been described. Accordingly, this study aimed: (1) to screen laboratory-kept rhesus monkeys for hemoplasmas; (2) to verify if any of the hemoplasma-positive animals demonstrate a decrease in their red blood cells counts; and (3) to investigate the genetic diversity of hemoplasma species in monkeys from Brazil. Five out of eight (62.5%) rhesus monkeys tested positive for hemoplasmas using a technique that detects DNA from these bacteria in monkey’s blood. Further analysis demonstrated that rhesus monkeys were infected by a species named ‘Candidatus Mycoplasma haematomacacae’ that had already been described occurring in monkeys from Japan and USA. Although no decreases on red blood cells count were perceived in rhesus monkeys evaluated herein, future studies are needed to elucidate if ‘Ca. M. haematomacacae’ is a problem for research studies that use rhesus monkeys.

Abstract

Health monitoring programs in animals used as experimental models are essential, since only disease-free subjects are considered suitable for research purposes. In laboratory-kept animals, hemoplasmas have been described as an important confounding variable. Different hemoplasma species have been detected infecting non-human primates (NHP) from Brazil. However, the occurrence of hemoplasma species in laboratory-kept NHP in Brazil has not-yet been assessed. Accordingly, this study aimed (i) to screen laboratory-kept rhesus monkeys for hemoplasmas, (ii) to verify if any of the hemoplasma-positive animals demonstrate hematological abnormalities, and (iii) to assess the genotype diversity of hemoplasma species in NHP from Brazil. Five out of eight (62.5%; 95% CI: 3.05–8.63) rhesus monkeys tested positive for hemotropic Mycoplasma spp. by PCR. Sequencing, phylogenetic, distance, and genotype diversity analyses of partial 16S rRNA gene demonstrate that rhesus monkeys were infected by ‘Candidatus Mycoplasma haematomacacae’ (formerly ‘Candidatus Mycoplasma haemomacaque’). Assessments of partial 16S rRNA diversity of hemoplasma species in NHP suggest that at least four genetically diverse groups may occur in Brazil. Although no hematological abnormalities were demonstrated in rhesus monkeys evaluated herein, future studies are needed to elucidate the influence of ‘Ca. M. haematomacacae’ as a confounding variable on research studies.

Haemoplasma Prevalence and Diversity in Three Invasive Rattus Species from Gauteng Province, South Africa

Invasive Rattus species are carriers of haemotropic Mycoplasmas (haemoplasmas) globally, but data from Africa are lacking. Using a PCR-sequencing approach, we assessed haemoplasma prevalence and diversity in kidney and buccal swabs collected from three invasive Rattus species (Rattus rattus, R. norvegicus and R. tanezumi) in Gauteng Province, South Africa. Whilst the overall sequence-confirmed haemoplasma prevalence was 38.4%, infection rates in R. rattus (58.3%) were significantly higher (χ2 = 12.96; df = 2; n = 99 p < 0.05) than for R. tanezumi (14.3%). Differences between host sex (χ2 = 3.59 × 10−31; df = 1; n = 99; p = 1.00) and age (χ2 = 4.28; df = 2; n = 99; p = 0.12) were not significant. Whilst buccal (1.01%) and ectoparasite positivity (2.13%) were low, these results suggest that multiple transmission routes are possible. Three phylogenetically distinct lineages, consistent with global rat-associated strains described to date, were detected, namely, ‘Candidatus Mycoplasma haemomuris subsp. Ratti’, and two Rattus-specific haemoplasmas that are yet to be formally described. These results expand the known distribution of invasive rat-associated haemoplasmas and highlight the potential for pathogen co-invasion of new territories together with invading rodent hosts.

Molecular detection and genotype diversity of hemoplasmas in non-hematophagous bats and associated ectoparasites sampled in peri-urban areas from Brazil

Hemoplasmas have already been detected in bats in the United States of America, Spain, Australia, Chile, Brazil, Peru, Belize, Nigeria, Costa Rica, Germany, Switzerland and New Caledonia. The recent detection of hemoplasmas closely related to Mycoplasma haematohominis, an agent causing disease in humans, emphasizes the need for additional studies on the diversity of hemoplasmas in bats. The present work aimed to investigate the occurrence and assess the phylogenetic positioning and genetic diversity of hemoplasmas in bats and associated ectoparasites sampled in central-western Brazil. Overall, 43% (58/135) sampled bats and 1.56% (1/64) bat flies (Megistopoda aranea) were positive for hemoplasmas, however, twenty-four and two hemoplasma sequences were obtained from PCR assays targeting 16S and 23S rRNA genes, respectively, since the majority of the obtained amplicons showed faint bands in agarose gel electrophoresis. The obtained 16S rRNA sequences showed to be broadly distributed along the phylogenetic tree, albeit positioned within the 'Haemofelis group' and clustering with other bat-associated hemoplasmas. Twelve 16S rRNA hemoplasma genotypes were found among the 24 obtained sequences. When compared to other bat-related hemoplasmas sequences retrieved from the Genbank, 52 genotypes were found. The two 23S rRNA sequences obtained were positioned as a sister clade to "Candidatus Mycoplasma haematohydrochaerus", M. haemofelis and M. haemocanis. High genetic diversity was found among 16S rRNA hemoplasma sequences detected in non-hematophagous bats from central-western Brazil and previously detected in other regions of the world. Even though the genotype analysis showed that hemoplasmas from the same genus tend to group together, the results from the unipartite and bipartite analyses did not robustly support the hypothesis. Further studies addressing the specificity of hemoplasma genotypes according to bat species and genera should be performed.

'Candidatus Mycoplasma haematonasua' and tick-borne pathogens in ring-tailed coatis (Nasua nasua Linnaeus, 1976) from the Iguaçu National Park, Paraná State, southern Brazil

The Iguaçu National Park (INP) is the largest remnant of Atlantic Forest in southern Brazil, representing an ecological continuum with Argentina. The INP harbours a diverse fauna, with ring-tailed coatis (Nasua nasua Linnaeus, 1976, Carnivora: Procyonidae) in close contact with tourists either begging and/or snatching food from visitors. A potentially novel haemotropic Mycoplasma sp. has been previously detected in the ring-tailed coatis from central-western and southern Brazil. Therefore, the aims of this study were to investigate the occurrence of haemotropic Mycoplasma sp. and tick-borne pathogens in wild ring-tailed coatis from the INP, Foz do Iguaçu municipality, Paraná State, southern Brazil. Blood samples were collected from 18 wild ring-tailed coatis and evaluated by conventional PCR (cPCR) assays for haemotropic Mycoplasma spp. (16S and 23S rRNA), Theileria/Babesia spp. (18S rRNA) and Ehrlichia/Anaplasma spp. (16S rRNA, sodB, dsb and groEL). Eight out of 18 (44.44%; 95% CI: 24.56%-66.28%) animals were positive for haemotropic Mycoplasma spp. All ring-tailed coatis tested negative for Theileria/Babesia spp. and only one out of 18 (5.56%; 95% CI: 0.99%-25.76%) animals tested positive for Ehrlichia/Anaplasma spp. by the 16S rRNA cPCR. Unfortunately, multiple attempts to sequence the 16S rRNA gene of the Ehrlichia/Anaplasma-positive sample have failed. Phylogenetic and network analysis of the hemoplasma 16S and 23S rRNA gene fragments confirmed that animals were infected by a potentially novel haemotropic Mycoplasma sp. previously reported in ring-tailed coatis from Brazil. The name 'Candidatus Mycoplasma haematonasua' is proposed for this novel organism.

The dilution effect behind the scenes: testing the underlying assumptions of its mechanisms through quantifying the long-term dynamics and effects of a pathogen in multiple host species

Disentangling the mechanisms that mediate the relationships between species diversity and disease risk has both theoretical and applied implications. We employed a model system of rodents and their Mycoplasma pathogens, in which an extreme negative diversity-disease relationship was demonstrated, to test the assumptions underlying three mechanisms that may explain this field pattern. Through quantifying the long-term dynamics and effects of the pathogen in its three host species, we estimated the between-host differences in pathogen spreading and transmission potentials, and host recovery potential and vulnerability to infection. The results suggest that one of the hosts is a pathogen amplifier and the other two hosts function as diluters. Considering the similarity in infection success and intensity among hosts, and the failure to detect any pathogen-induced damage, we could not validate the assumption underlying the hypotheses that diluters reduce the overall transmission or increase the mortality of infected hosts in the system. Instead, the results demonstrate that diluters clear the infection faster than amplifiers, supporting the possibility that the addition of diluters to the community may reduce the overall number of infected hosts through this mechanism. This study highlights the contribution of experimental studies that simultaneously explore different aspects of host-pathogen interactions in multiple hosts, in diversity-disease research.

'Candidatus Mycoplasma haemosphiggurus' a novel haemoplasma species in orange-spined hairy dwarf porcupines (Sphiggurus villosus) from Southern Brazil

In Brazil, the orange-spined hairy dwarf porcupine (Sphiggurus villosus) is widely distributed in the Atlantic Rainforest biome being amongst the most frequently road-killed animal. Porcupines may also be commonly found on forest borders and occasionally, near urban areas where human and domestic dogs injuries caused by its spines may occur. Therefore, the aims of this study were (a) to screen porcupines for TBD pathogens and haemoplasmas and (b) to identify the tick species parasitizing these rodents in Paraná State, southern Brazil. Blood and/or spleen samples were collected from nine orange-spined hairy dwarf porcupines. A total of 275 ticks (34 males, 11 females, 7 nymphs and 223 larvae) were collected from eight porcupines: Amblyomma longirostre, A. parkeri and Amblyomma spp. larvae. Two out of nine (22%; 95% CI: 3%-60%) porcupines were PCR-positive for haemoplasmas. All animals tested negative for Theileria/Babesia spp. and Ehrlichia/Anaplasma spp. by PCR. Phylogenetic and network analysis of the 16S and 23S rRNA gene fragments confirmed that animals were infected by a potentially novel haemotropic Mycoplasma sp. The name 'Candidatus Mycoplasma haemosphiggurus' is proposed for this novel organism that should be further fully characterized.

Molecular detection and characterization of novel haemotropic Mycoplasma in free-living mole rats from South Africa

The importance of haemotropic Mycoplasma (haemoplasma) infections to animal and human health is increasingly recognised. Although wild rodents are known to host these bacteria, haemoplasma prevalence and diversity in small mammals is under-documented, globally. This is due to the reliance on molecular approaches to detect these unculturable, obligate bacteria and to a paucity of assays targeting informative gene regions. We attempted to address these challenges by evaluating the performance of three 16S rRNA PCR assays for detecting Mycoplasma in four African mole-rat species of the family Bathyergidae. This was achieved by screening DNA samples prepared from lung and liver samples of 260 bathyergids, sampled from natural and urban landscapes in the Western Cape Province with one published and two novel conventional PCR assays. Sequence-confirmed Mycoplasma presence guided calculations of the relative sensitivity and specificity of the assays and revealed that 26.5% of the rodents were haemoplasma-positive. Bathyergus suillus sampled near an informal human settlement had a significantly higher infection rate (42%) than the three bathyergid species sampled from natural settings, for which PCR-positivity ranged from 0% to 36%. The 16S rRNA gene phylogeny identified the presence of six Mycoplasma strains in bathyergids that form a novel monophyletic lineage belonging to the haemofelis group, with 16S rRNA and Rnase P gene phylogenies indicating that the bathyergid-associated haemoplasmas were novel and closely related to Mycoplasma coccoides. Assay sensitivity ranged from 60.3% to 76.8% and specificity from 94.8% to 100% and both were highest for the novel assay targeting a ~ 300 bp region of the 16S rRNA gene. Results confirm the presence of novel haemoplasma strains in bathyergid species from South Africa and emphasise the need for expanded studies on haemoplama prevalence, diversity, and transmission routes in other small mammal species from this biodiverse region.

The Enemy Within: How Does a Bacterium Inhibit the Foraging Aptitude and Risk Management Behavior of Allenby's Gerbils?

AbstractMicrobes inhabiting multicellular organisms have complex, often subtle effects on their hosts. Gerbillus andersoni allenbyi are commonly infected with Mycoplasma haemomuris-like bacteria, which may cause mild nutrient (choline, arginine) deficiencies. However, are there more serious ecological consequences of infection, such as effects on foraging aptitudes and risk management? We tested two alternatives: the nutrient compensation hypothesis (does nutrient deficiency induce infected gerbils to make up for the shortfall by foraging more and taking greater risks?) and (2) the lethargy hypothesis (do sick gerbils forage less, and are they compromised in their ability to detect predators or risky microhabitats?). We compared the foraging and risk management behavior of infected and noninfected gerbils. We experimentally infected gerbils with the bacteria, which allowed us to compare between noninfected, acutely infected (peak infection loads), and chronically infected (low infection loads) individuals. Our findings supported the lethargy hypothesis over the nutrient compensation hypothesis. Infected individuals incurred dramatically elevated foraging costs, including less efficient foraging, diminished "quality" of time spent vigilant, and increased owl predation. Interestingly, gerbils that were chronically infected (lower bacteria load) experienced larger ecological costs than acutely infected individuals (i.e., peak infection loads). This suggests that the debilitating effects of infection occur gradually, with a progressive decline in the quality of time gerbils allocated to foraging and managing risk. These increased long-term costs of infection demonstrate how small direct physiological costs of infection can lead to large indirect ecological costs. The indirect ecological costs of this parasite appear to be much greater than the direct physiological costs.

Worldwide occurrence of haemoplasmas in wildlife: Insights into the patterns of infection, transmission, pathology and zoonotic potential

Haemotropic mycoplasmas (haemoplasmas) have increasingly attracted the attention of wildlife disease researchers due to a combination of wide host range, high prevalence and genetic diversity. A systematic review identified 75 articles that investigated haemoplasma infection in wildlife by molecular methods (chiefly targeting partial 16S rRNA gene sequences), which included 131 host genera across six orders. Studies were less common in the Eastern Hemisphere (especially Africa and Asia) and more frequent in the Artiodactyla and Carnivora. Meta-analysis showed that infection prevalence did not vary by geographic region nor host order, but wild hosts showed significantly higher prevalence than captive hosts. Using a taxonomically flexible machine learning algorithm, we also found vampire bats and cervids to have greater prevalence, whereas mink, a subclade of vesper bats, and true foxes all had lower prevalence compared to the remaining sampled mammal phylogeny. Haemoplasma genotype and nucleotide diversity varied little among wild mammals but were marginally lower in primates and bats. Coinfection with more than one haemoplasma species or genotype was always confirmed when assessed. Risk factors of infection identified were sociality, age, males and high trophic levels, and both prevalence and diversity were often higher in undisturbed environments. Haemoplasmas likely use different and concurrent transmission routes and typically display enzootic dynamics when wild populations are studied longitudinally. Haemoplasma pathology is poorly known in wildlife but appears subclinical. Candidatus Mycoplasma haematohominis, which causes disease in humans, probably has it natural host in bats. Haemoplasmas can serve as a model system in ecological and evolutionary studies, and future research on these pathogens in wildlife must focus on increasing the geographic range and taxa of studies and elucidating pathology, transmission and zoonotic potential. To facilitate such work, we recommend using universal PCR primers or NGS protocols to detect novel haemoplasmas and other genetic markers to differentiate among species and infer cross-species transmission.

Molecular Survey and Genetic Diversity of Hemoplasmas in Rodents from Chile

Even though hemotrophic mycoplasma (hemoplasma) infections are well documented in a wide variety of hosts worldwide, there is a gap in the knowledge aobut hemoplasmas in rodents. This study aimed to molecularly survey and investigate the genetic diversity of hemoplasmas in rodents from Chile. Synanthropic and wild rodents (n = 74) were captured in the southern province of Valdivia (Corral, Valdivia, Riñihue, and Reumén localities). Spleen samples were submitted to a conventional PCR for hemotrophic Mycoplasma spp. targeting the 16S rRNA gene (800 bp), followed by sequencing, phylogenetic, and genetic diversity analyses. The overall occurrence of hemotrophic mycoplasmas in rodents from Valdivia was 24.5% (18/74) [95% CI (14.5; 34.1)]. Hemoplasmas were detected in Mus musculus (1/4), Rattus norvegicus (1/16), Abrothrix longipilis (7/13), A. olivaceo (6/8), and Oligoryzomys longicaudatus (3/10). The nucleotide polymorphism analysis of the targeted 16S rRNA region showed low diversity, with two genotypes and a high identity to the variants detected in wild rodents from Brazil. Hemoplasmas are described for the first time in rodents from Chile with a moderate occurrence and low 16S rDNA genetic diversity within the sampled rodent population. The detected hemoplasma genotypes were specific to rodents and were not shared with other mammals.

'Candidatus Mycoplasma haemoalbiventris', a novel hemoplasma species in white-eared opossums (Didelphis albiventris) from Brazil

Opossums of the genus Didelphis are considered synanthropic animals due to their close contact with human beings. Previously, two species of hemotropic mycoplasmas (hemoplasmas) have been detected in opossums: 'Candidatus Mycoplasma haemodidelphidis' in the North American opossum (Didelphis virginiana) and a potentially novel hemotropic Mycoplasma sp. in the white-eared opossums (Didelphis albiventris) from Brazil. Accordingly, the aims of this study were as follows: (a) to determine the prevalence of hemotropic Mycoplasma spp. in free-ranging opossums, (b) to characterize molecularly the hemotropic Mycoplasma sp. infecting opossums and (c) to determine factors associated with hemoplasma infection in opossums from Canoinhas municipality, Santa Catarina State, southern Brazil. For this purpose, 50 white-eared opossums (33 captured and 17 road-killed animals) were evaluated by a pan-hemoplasma PCR assay based on 16S rRNA. Six out of 50 (12%; 95% CI: 5.6%-23.8%) opossums were infested by Ctenocephalides felis fleas. Twenty out of 50 (40%; 95% CI: 26.41%-54.82%) opossums tested positive for hemotropic Mycoplasma sp. by PCR. Sequencing and phylogenetic analysis of the 16S and 23S rRNA gene fragments confirmed that animals were infected by a potentially novel hemotropic Mycoplasma sp. previously reported in white-eared opossums from Brazil. No significant association was found between gender (p = .7759), trap area (p = .0887) or presence of fleas (p = .3811) and positivity for hemoplasmas. The potentially novel hemoplasma species seems to be highly prevalent in white-eared opossums from the states of Paraná, Santa Catarina and Mato Grosso do Sul. Based on the phylogenetic analyses of the 16S rRNA and 23S rRNA genes along with epidemiological data, the name 'Candidatus Mycoplasma haemoalbiventris' is proposed for this novel organism.

Ecological and evolutionary drivers of haemoplasma infection and bacterial genotype sharing in a Neotropical bat community

Most emerging pathogens can infect multiple species, underlining the importance of understanding the ecological and evolutionary factors that allow some hosts to harbour greater infection prevalence and share pathogens with other species. However, our understanding of pathogen jumps is based primarily around viruses, despite bacteria accounting for the greatest proportion of zoonoses. Because bacterial pathogens in bats (order Chiroptera) can have conservation and human health consequences, studies that examine the ecological and evolutionary drivers of bacterial prevalence and barriers to pathogen sharing are crucially needed. Here were studied haemotropic Mycoplasma spp. (i.e., haemoplasmas) across a species-rich bat community in Belize over two years. Across 469 bats spanning 33 species, half of individuals and two-thirds of species were haemoplasma positive. Infection prevalence was higher for males and for species with larger body mass and colony sizes. Haemoplasmas displayed high genetic diversity (21 novel genotypes) and strong host specificity. Evolutionary patterns supported codivergence of bats and bacterial genotypes alongside phylogenetically constrained host shifts. Bat species centrality to the network of shared haemoplasma genotypes was phylogenetically clustered and unrelated to prevalence, further suggesting rare-but detectable-bacterial sharing between species. Our study highlights the importance of using fine phylogenetic scales when assessing host specificity and suggests phylogenetic similarity may play a key role in host shifts not only for viruses but also for bacteria. Such work more broadly contributes to increasing efforts to understand cross-species transmission and the epidemiological consequences of bacterial pathogens.

Genetic diversity and lack of molecular evidence for hemoplasma cross-species transmission between wild and synanthropic mammals from Central-Western Brazil

Globally, hemotropic mycoplasmas (hemoplasmas) comprise an emerging or remerging bacteria group that attaches to red blood cells of several mammal's species and in some cases, causing hemolytic anemia. Herein, we assessed the occurrence, genetic diversity, the factors coupled to mammals infection, and the phylogeographic distribution of hemoplasmas in sylvatic and synanthropic mammals and their associated ectoparasites from Brazil. We collected spleen and/or blood samples from synanthropic rodents (Rattus rattus [N = 39] and Mus musculus [N = 9]), sylvatic rodents (Hydrochoerus hydrochaeris [N = 14]) and opossums (Didelphis albiventris [N = 43]). In addition, ticks (Amblyomma spp. [N = 270] and lice (Polyplax spinulosa [N = 6]) specimens were also sampled. Using a PCR targeting the 16S rRNA region, out of 48 small rodents, 14 capybaras and 43 opossums DNA samples, hemoplasma DNA was found in 25%, 50%, and 32.5% animals, respectively. Besides, we reported hemoplasma DNA in Amblyomma sp. (22.2% [2/9]) and lice (100% [2/2]) pools samples from rats, and one female A. sculptum DNA sample (3% [1/33]) obtained from a capybara. Additionally, and in agreement with ML analysis, the network analyses showed a clear phylogenetic separation among the hemoplasmas genotypes found in the different host species sampled, thus, suggesting the absence of cross-species hemoplasmas transmission between the mammals trapped. Finally, using the NTC network analysis, we reported the same 16S rRNA Mycoplasma genotype circulating in Rattus sampled in Brazil, Hungary, and Japan.

The dynamics between limited-term and lifelong coinfecting bacterial parasites in wild rodent hosts

Interactions between coinfecting parasites may take various forms, either direct or indirect, facilitative or competitive, and may be mediated by either bottom-up or top-down mechanisms. Although each form of interaction leads to different evolutionary and ecological outcomes, it is challenging to tease them apart throughout the infection period. To establish the first step towards a mechanistic understanding of the interactions between coinfecting limited-term bacterial parasites and lifelong bacterial parasites, we studied the coinfection of Bartonella sp. (limited-term) and Mycoplasma sp. (lifelong), which commonly co-occur in wild rodents. We infected Bartonella- and Mycoplasma-free rodents with each species, and simultaneously with both, and quantified the infection dynamics and host responses. Bartonella benefited from the interaction; its infection load decreased more slowly in coinfected rodents than in rodents infected with Bartonella alone. There were no indications for bottom-up effects, but coinfected rodents experienced various changes, depending on the infection stage, in their body mass, stress levels and activity pattern, which may further affect bacterial replication and transmission. Interestingly, the infection dynamics and changes in the average coinfected rodent traits were more similar to the chronic effects of Mycoplasma infection, whereas coinfection uniquely impaired the host's physiological and behavioral stability. These results suggest that parasites with distinct life history strategies may interact, and their interaction may be asymmetric, non-additive, multifaceted and dynamic through time. Because multiple, sometimes contrasting, forms of interactions are simultaneously at play and their relative importance alternates throughout the course of infection, the overall outcome may change under different ecological conditions.