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Leptospirosis and Lyme borreliosis are zoonotic emerging diseases of global importance and wide distribution. The aim of this study was to detect by molecular testing to Leptospira interrogans and Borrelia burgdorferi sensu lato in wild rodents from Nuevo Leon, Quintana Roo, and Campeche, Mexico. This study is the first in report to Chaetodipus nelsoni, Dipodomys merriami, and Peromyscus eremicus infected with L. interrogans in Mexico. Besides, Chaetodipus hispidus, Heteromys gaumeri, Heteromys irroratus, Neotoma micropus, Peromyscus leucopus, Peromyscus maniculatus, and Sigmodon hispidus infected with B. burgdorferi s.l. in Mexico. Also, is the first report in identify coinfection of L. interrogans and B. burgdorferi s.l. in wild rodents such as H. irroratus and S. hispidus in Nuevo Leon, and H. gaumeri in Quintana Roo, Mexico. These wild rodent species infected represent a risk factor for the exposed population in these sylvatic and rural areas of Mexico.

Dry jungles harbor a large number of species with restricted distribution or endemic, and little is known about the ecological processes involving these species. Such as activity periods, diet, or predation. In October 2016, we registered a predation event on the Mexican endemic rodent Xenomys nelsoni by the colubrid snake Senticolis triapsis in the Chamela-Cuixmala Biosphere Reserve. This rodent species is listed as endangered by the Mexican law. This is the first report of predation on individuals of this threatened rodent genus.

Leptospirosis and Lyme borreliosis are zoonotic emerging diseases of global importance and wide distribution. The aim of this study was to detect by molecular testing to

Se evaluó la influencia de la transformación antropogénica del paisaje por actividades pecuarias sobre la composición y especificidad de las comunidades de ectoparásitos asociadas a murciélagos, en ranchos ganaderos del estado de Veracruz. Se compararon sitios con diferente nivel de transformación del paisaje que incluyeron producciones bajo sistemas de pastoreo en acahual, silvopastoril y pastizal. Se capturaron 944 murciélagos de 23 especies en ocho unidades de producción pecuaria. Se realizó la identificación taxonómica de 1 433 ectoparásitos de 35 especies obtenidos a partir de 428 hospederos. Se realizaron análisis de diversidad taxonómica y especificidad filogenética entre las asociaciones murciélago-ectoparásito. La composición de las comunidades de ectoparásitos asociadas con Artibeus jamaicensis mostró diferencias significativas entre los tres niveles de transformación del paisaje. El acahual, que es el paisaje con menor transformación antropogénica, presentó los valores más altos de diversidad de especies de murciélagos y de ectoparásitos. La filoespecificidad de los estréblidos no presentó cambios significativos entre los diferentes tipos de paisaje del estudio. La consideración de factores antropogénicos que afecten la riqueza, abundancia y diversidad de los ectoparásitos, así como la relación filogenética con sus hospederos es esencial para profundizar en el estudio de las asociaciones hospedero-parásito.

Bats are reservoirs for viruses with zoonotic potential in the Americas, and scattered evidence exists suggesting that bats may act as reservoirs for dengue virus (DENV). To explore further the role of bats as part of DENV sylvatic cycles, 240 bats of 18 species were captured in 2 states of Mexico with contrasting ecological characteristics but concurrent DENV activity in humans. RT-PCR analysis of RNA extracted from liver or spleen tissue from de bats failed to show evidence for the presence of DENV nucleic acids in these organs. In addition, plasma assayed by plaque reduction neutralization test showed no evidence of neutralizing anti-DENV antibodies. These results suggest that American bats may not be reservoirs or amplification host for DENV infection.

To understand the mechanisms driving species diversity is central to community ecology. Here, we explored if habitat partitioning is associated with a species-rich ectoparasite community in small rodents from a tropical dry forest in western Mexico. We trapped 199 mice in three 0.5 ha-plots from eight small rodent species for every two months, from July 2011 to April 2012, and collected their ectoparasites. We identified 17 species of mites, two sucking lice species, two phoretic species, and one commensal species. The most abundant ectoparasite species was Steptolaelaps liomydis, representing 42 percent of all ectoparasites collected; seven ectoparasite species had < 10 individuals. Eighteen ectoparasite species (of 22 species) were collected from the most abundant rodent Liomys pictus. C-score and the number of checkerboard species pairs were significantly higher against a random expectation. Ectoparasite species in L. pictus mice showed host microhabitat partitioning; Fahrenholzia ehrlichi and Fahrenholzia texana were found only in the anterior dorsal area, Ornithonysus sp. occurred along the dorsal part, Ixodes species were restricted to the ears, and Steptolaelaps liomydis was found throughout the body. We also identified ectoparasite communities with distinct species composition in two rodent species that use contrasting macrohabitats (L. pictus, strictly terrestrial; Peromyscus perfulvus, mostly arboreal). The remaining and low abundant rodent species showed a species-poor ectoparasite community composition. We conclude that habitat partitioning at both macro and microhabitat scales appeared to characterize the species-rich ectoparasite community. Conversely, most rodent host species with low abundances showed a species-poor ectoparasite community. Resumen Entender los mecanismos que promueven la diversidad de especies es una pregunta central en ecologia de comunidades. En este trabajo exploramos si la reparticion del habitat se utiliza como mecanismo para mantener una comunidad rica en especies de ectoparasitos. Se colectaron 199 individuos roedores pequenos, pertenecientes a ocho especies, con trampas Sherman en tres parcelas de ca. 0,5 ha, en un bosque tropical seco del oeste de Mexico, de julio de 2011 a abril de 2012. Se colectaron los ectoparasitos al momento de la manipulacion de los roedores capturados en campo y en el laboratorio. Se identificaron 17 especies de acaros, dos especies de piojos y dos especies foreticas y una comensal. La especie mas abundante de ectoparasitos fue Steptolaelaps liomydis, que represento alrededor del 42 por ciento de los individuos colectados; siete especies tuvieron

Leishmaniases are a group of important diseases transmitted to humans through the bite of sandfly vectors. Several forms of leishmaniases are endemic in Mexico and especially in the Southeast region. In the Northeastern region, however, there have only been isolated reports of cases and scanty records of sandfly vectors. The main objective of this study was to analyze the diversity of sandflies and potential reservoir hosts of Leishmania spp. in the states of Nuevo Leon and Tamaulipas. Species richness and abundances of sandflies and rodents were recorded. A fraction of the caught sandflies was analyzed by PCR to detect Leishmania spp. Tissues from captured rodents were also screened for infection. Ecological Niche Models (ENMs) were computed for species of rodent and their association with crop-growing areas. We found 13 species of sandflies, several of which are first records for this region. Medically important species such as Lutzomyia anthophora , Lutzomyia diabolica , Lutzomyia cruciata , and Lutzomyia shannoni were documented. Leishmania spp. infection was not detected in sandflies. Nine species of rodents were recorded, and Leishmania (Leishmania ) mexicana infection was found in four species of Peromyscus and Sigmodon . ENMs showed that potential distribution of rodent pest species overlaps with allocated crop areas. This shows that Leishmania (L .) mexicana infection is present in the Northeastern region of Mexico, and that previously unrecorded sandfly species occur in the same areas. These findings suggest a potential risk of transmission of Leishmania (L. ) mexicana .

Species distribution models were constructed for tenIxodesspecies andAmblyomma cajennensefor a region including Mexico and Texas. The model was based on a maximum entropy algorithm that used environmental layers to predict the relative probability of presence for each taxon. For Mexico, species geographic ranges were predicted by restricting the models to cells which have a higher probability than the lowest probability of the cells in which a presence record was located. There was spatial nonconcordance between the distributions ofAmblyomma cajennenseand theIxodesgroup with the former restricted to lowlands and mainly the eastern coast of Mexico and the latter to montane regions with lower temperature. The risk of Lyme disease is, therefore, mainly present in the highlands where someIxodesspecies are known vectors; ifAmblyomma cajennenseturns out to be a competent vector, the area of risk also extends to the lowlands and the east coast.

Leishmania (Leishmania) mexicana causes cutaneous leishmaniasis, an endemic zoonosis affecting a growing number of patients in the southeastern states of Mexico. Some foci are found in shade-grown cocoa and coffee plantations, or near perennial forests that provide rich breeding grounds for the sand fly vectors, but also harbor a variety of bat species that live off the abundant fruits provided by these shade-giving trees. The close proximity between sand flies and bats makes their interaction feasible, yet bats infected with Leishmania (L.) mexicana have not been reported. Here we analyzed 420 bats from six states of Mexico that had reported patients with leishmaniasis. Tissues of bats, including skin, heart, liver and/or spleen were screened by PCR for Leishmania (L.) mexicana DNA. We found that 41 bats (9.77%), belonging to 13 species, showed positive PCR results in various tissues. The infected tissues showed no evidence of macroscopic lesions. Of the infected bats, 12 species were frugivorous, insectivorous or nectarivorous, and only one species was sanguivorous (Desmodus rotundus), and most of them belonged to the family Phyllostomidae. The eco-region where most of the infected bats were caught is the Gulf Coastal Plain of Chiapas and Tabasco. Through experimental infections of two Tadarida brasiliensis bats in captivity, we show that this species can harbor viable, infective Leishmania (L.) mexicana parasites that are capable of infecting BALB/c mice. We conclude that various species of bats belonging to the family Phyllostomidae are possible reservoir hosts for Leishmania (L.) mexicana, if it can be shown that such bats are infective for the sand fly vector. Further studies are needed to determine how these bats become infected, how long the parasite remains viable inside these potential hosts and whether they are infective to sand flies to fully evaluate their impact on disease epidemiology., Author Summary Leishmaniasis is endemic in southeastern Mexico, where Leishmania (L.) mexicana is the principle parasite species causing disease in humans. Previous studies using methodology for inferring potential biotic interactions between species had shown a high prevalence of bat species as potential hosts for Leishmania, yet bats have not been identified as hosts in Mexico. Motivated by these predictions, we currently analyze whether bats are infected with Leishmania (L.) mexicana and to what extent they serve as hosts for this parasite. We analyzed 420 bats from six states, and through PCR analysis of skin, heart, liver and/or spleen we found that 41 bats (9.77%) of 13 different bat species were infected. Most of the infected bats were netted in an eco-region characterized by plantations grown beneath shade-providing fruit trees that favors breeding conditions for the sand fly vectors and brings them in close proximity with frugivorous, insectivorous or nectarivorous bats. None of the infected bat tissues showed macroscopic lesions. Through artificial infections, we were also able to show that Leishmania (L.) mexicana remains viable and infective after passage through one species of bat. We conclude that various species of bats belonging to the family Phyllostomidae are possible reservoir hosts of Leishmania (L.) mexicana.

Dengue is the most important mosquito-borne viral disease to humans. Bats are potential reservoirs for flaviviruses, including dengue virus (DENV). In this work, Artibeus jamaicensis bats were inoculated with two serotypes of DENV using different routes. For experimental inoculations (EI) 1 and 2, bats were inoculated subcutaneously or intraperitoneally with DENV-4; for EI-3 bats were inoculated intraperitoneally with DENV-1. Mock inoculated bats were kept as controls. In EI-4, bats were bitten by Aedes aegypti mosquitoes infected with DENV-1 or 4. Reverse transcription-polymerase chain reaction assays in plasma and spleen tissue collected from Day 1 to Days 9-17 after inoculation failed to reveal the presence of viral RNA in any of the samples. No evidence of circulating NS1 or specific anti-DENV IgG was detected in the plasma of the inoculated bats. These results indicate that A. jamaicensis bats are incapable of sustaining dengue virus replication and are unlikely to act as reservoirs for this virus.

Zoonoses are an important class of infectious diseases. An important element determining the impact of a zoonosis on domestic animal and human health is host range. Although for particular zoonoses some host species have been identified, until recently there have been no methods to predict those species most likely to be hosts or their relative importance. Complex inference networks infer potential biotic interactions between species using their degree of geographic co-occurrence, and have been posited as a potential tool for predicting disease hosts. Here we present the results of an interdisciplinary, empirical study to validate a model based on such networks for predicting hosts of Leishmania (L.) mexicana in Mexico. Using systematic sampling to validate the model predictions we identified 22 new species of host (34% of all species collected) with the probability to be a host strongly dependent on the probability of co-occurrence of vector and host. The results confirm that Leishmania (L.) mexicana is a generalist parasite but with a much wider host range than was previously thought. These results substantially change the geographic risk profile for Leishmaniasis and provide insights for the design of more efficient surveillance measures and a better understanding of potential dispersal scenarios., Author Summary Emerging and neglected zoonoses are an important global threat to public health. Host range, in particular, is a crucial factor in determining disease risk and the potential for adequate interventions. Here we show that Leishmania has a very wide host range and that Complex Inference Networks can be used to infer ecological relationships in the context of zoonoses, identifying both the potential hosts and their relative importance. These results substantially change the risk profile and potential control measures that can be used to combat the disease, allowing for the design of more efficient surveillance measures and a better understanding of potential dispersal scenarios.

ResumenLos mamíferos son uno de los grupos más conspicuos de las comunidades terrestres de vertebrados y muestran una serie de características internas y externas que los han llevado a ser exitosos en casi todos los ecosistemas del mundo. El objetivo de esta revisión es actualizar el estado de conocimiento de los mamíferos de México. En México los mamíferos forman un grupo altamente diverso, ubicando al país en el tercer lugar mundial con 564 especies silvestres, alcanzando aproximadamente el 10% de la diversidad total. La descripción de las especies no ha sido homogénea a lo largo del tiempo y tuvo un mayor auge desde mediados de 1700 hasta 1950. La distribución de los mamíferos incluye todo el territorio nacional; el 77% son especies menores a 5kg y pertenecen, principalmente, a los órdenes Rodentia, Chiroptera y Soricomorpha. Las tendencias poblacionales están poco documentadas en la mayoría de los órdenes pero, en general, los mamíferos han visto disminuidas sus poblaciones como resultado de las actividades antrópicas. La información analizada sugiere que a pesar de que el grupo de los mamíferos en México es uno de los más estudiados, continúa ofreciendo interesantes retos teóricos y de manejo.AbstractMammals constitute one of the most conspicuous groups of terrestrial vertebrates showing internal and external characteristics that have allowed them to be successful in virtually all ecosystems worldwide. The objective of this revision is to update the current knowledge of mammals occurring in Mexico. In Mexico mammals constitute a highly diverse group, ranking third worldwide with 564 species, representing close to 10% of the total mammal fauna. The description of mammals in Mexico has been uneven through time; a significant increase occurred from 1700 to 1950. Mammals are distributed nationwide; a total of 77% of species are less than 5kg, belonging to the Orders Rodentia, Chiroptera and Soricomorpha. Population trends are poorly documented in most species, but it is likely that populations have been negatively affected by human activities. We conclude that despite mammals are a well-studied group compared with other vertebrates, they continue to offer interesting theoretical insights and challenges for their conservation and sustainable use.