Transmisión vertical del virus de la rabia cría-madre, fenómeno que podría mantener al virus en especies reservorios de vida silvestre.

INTRODUCTION: The biological test established by the World Health Organization to isolate and amplify the rabies virus consists in inoculating lactating mice by intracranial route and detecting rabies signs for 21 days. OBJECTIVE: To verify viral transmission in mothers of rabies virus-inoculated lactating mice. METHOD: Twenty-seven Mexican rabies virus isolates were inoculated by intracranial route in lactating mice, which were observed for 21 days. The mothers were observed for 60 days. The diagnosis was established by immunofluorescence in brain tissue. The virus was characterized by sequencing and with monoclonal antibodies. RESULTS: All litters showed rabies at between 7 and 15 days post-inoculation (p. i.). Three of the 27 females (11 %) had developed rabies at days 33, 37 and 39 p. i. of their litters. Viral characterization showed that the mothers were infected with the same variant of their offspring, two of them stemming from hematophagous bat and one from dog. The liters that transmitted rabies to their mothers were nine individuals. CONCLUSIONS: In nature, the rabies virus could be preserved by transmission from neonates (more susceptible to contracting and amplifying the rabies virus) to their mothers.

INTRODUCCIÓN: La prueba biológica establecida por la Organización Mundial de la Salud para aislar y amplificar el virus de la rabia consiste en inocular vía intracraneal ratones lactantes para detectar signos de rabia en un periodo de 21 días. OBJETIVO: Constatar el contagio viral en las madres de ratones lactantes inoculados con virus de la rabia. MÉTODO: Veintisiete aislados mexicanos de virus de la rabia se inocularon vía intracraneal en ratones lactantes, los cuales fueron observados por 21 días y sus madres, por 60 días. El diagnóstico se llevó a cabo mediante inmunofluorescencia en cerebro. El virus se caracterizó por secuenciación y anticuerpos monoclonales. RESULTADOS: Todas las camadas presentaron rabia entre siete y 15 días posinoculación (p. i.); tres de las 27 hembras (11 %), a los días 33, 37 y 39 p. i. de sus crías. La caracterización viral mostró que las madres se infectaron con la misma variante de sus crías, dos procedían de murciélago hematófago y una de perro. Las camadas que trasmitieron rabia a sus madres fueron nueve individuos. CONCLUSIONES: En la naturaleza, el virus de la rabia podría preservarse mediante la transmisión de los neonatos (más susceptibles de contraer y amplificar el virus) a sus madres.

Taxonomy of the order Mononegavirales: update 2018.

In 2018, the order Mononegavirales was expanded by inclusion of 1 new genus and 12 novel species. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV) and summarizes additional taxonomic proposals that may affect the order in the near future.

How Social Structure Drives the Population Dynamics of the Common Vampire Bat (Desmodus rotundus, Phyllostomidae).

Social systems are major drivers of population structure and gene flow, with important effects on dynamics and dispersal of associated populations of parasites. Among bats, the common vampire bat (Desmodus rotundus) has likely one of the most complex social structures. Using autosomal and mitochondrial markers on vampires from Mexico, French Guiana, and North Brazil, from both roosting and foraging areas, we observed an isolation by distance at the wider scale and lower but significant differentiation between closer populations (<50 km). All populations had a low level of relatedness and showed deviations from Hardy-Weinberg equilibrium and a low but significant inbreeding coefficient. The associated heterozygote deficiency was likely related to a Wahlund effect and to cryptic structures, reflecting social groups living in syntopy, both in roosting and foraging areas, with only limited admixture. Discrepancy between mitochondrial and nuclear markers suggests female philopatry and higher dispersal rates in males, associated with peripheral positions in the groups. Vampires are also the main neotropical reservoir for rabies virus, one of the main lethal pathogens for humans. Female social behaviors and trophallaxis may favor a rapid spread of virus to related and unrelated offspring and females. The high dispersal capacity of males may explain the wider circulation of viruses and the inefficacy of bat population controls. In such opportunistic species, gene connectivity should be considered for management decision making. Strategies such as culling could induce immigration of bats from neighboring colonies to fill vacant roosts and feeding areas, associated with the dispersal of viral strains.

Potentially Zoonotic Bartonella in Bats from France and Spain.

We detected Bartonella in 11 of 109 insectivorous bats from France and 1 of 26 bats from Spain. These genetic variants are closely related to bat-associated Bartonella described in Finland and the United Kingdom and to B. mayotimonensis, the agent of a human endocarditis case in the United States.

Molecular characterization of atypical antigenic variants of canine rabies virus reveals its reintroduction by wildlife vectors in southeastern Mexico.

Rabies is an infectious viral disease that is practically always fatal following the onset of clinical signs. In Mexico, the last case of human rabies transmitted by dogs was reported in 2006 and canine rabies has declined significantly due to vaccination campaigns implemented in the country. Here we report on the molecular characterization of six rabies virus strains found in Yucatan and Chiapas, remarkably, four of them showed an atypical reaction pattern when antigenic characterization with a reduced panel of eight monoclonal antibodies was performed. Phylogenetic analyses on the RNA sequences unveiled that the three atypical strains from Yucatan are associated with skunks. Analysis using the virus entire genome showed that they belong to a different lineage distinct from the variants described for this animal species in Mexico. The Chiapas atypical strain was grouped in a lineage that was considered extinct, while the others are clustered within classic dog variants.

Unraveling the diversity of Trypanosoma species from Central Mexico: Molecular confirmation on the presence of Trypanosoma dionisii and novel Neobat linages.

Bats are one of the groups of mammals with the highest number of associated Trypanosoma taxa. There are 50 Trypanosoma species and genotypes infecting more than 75 species of bats across five continents. However, in Mexico, the inventory of species of the genus Trypanosoma associated with bats is limited to only two species (Trypanosoma vespertilionis and Trypanosoma cruzi) even though 140 species of bats inhabit this country. Specifically, 91 bat species have been recorded in the state of Veracruz, but records of trypanosomatids associated with this mammalian group are absent. Due to the complex Trypanosoma-bat relationship, the high diversity of bat species in Veracruz, as well as the lack of records of trypanosomatids associated with bats for this state, the aim of this work was to analyze the diversity of species of the genus Trypanosoma and their presence from a bat community in the central area of the state of Veracruz, Mexico. During the period of January to August 2022 in the Tequecholapa Environmental Management Unit where bats were collected using mist nets and blood samples were obtained from their thumbs. We extracted genetic material and amplified a fragment of 800 bp of the 18S ribosomal gene of the genus Trypanosoma by conventional PCR. The positive amplicons were sequenced, and phylogenetic reconstruction was performed to identify the parasite species. A total of 285 bats (149♀, 136♂) belonging to 13 species from 10 genera and a single family (Phyllostomidae) were collected. Twenty-three specimens from six species tested positive for the presence of Trypanosoma dionisii, Trypanosoma sp. Neobat 4, and a potential novelty species provisionally named as Trypanosoma sp. Neobat 6. The results of the present work increase the number of species of the genus Trypanosoma infecting bats in Mexico and in the Neotropical region.

Novel lyssavirus in bat, Spain.

A new tentative lyssavirus, Lleida bat lyssavirus, was found in a bent-winged bat (Miniopterus schreibersii) in Spain. It does not belong to phylogroups I or II, and it seems to be more closely related to the West Causasian bat virus, and especially to the Ikoma lyssavirus.

Rabies surveillance in the United States during 2021.

OBJECTIVE: To provide epidemiological information on the occurrence of animal and human rabies in the US during 2021 and summaries of 2021 rabies surveillance for Canada and Mexico. PROCEDURES: State and territorial public health departments and USDA Wildlife Services provided data on animals submitted for rabies testing in 2021. Data were analyzed temporally and geographically to assess trends in domestic animal and wildlife rabies cases. RESULTS: During 2021, 54 US jurisdictions reported 3,663 rabid animals, representing an 18.2% decrease from the 4,479 cases reported in 2020. Texas (n = 456 [12.4%]), Virginia (297 [8.1%]), Pennsylvania (287 [7.8%]), North Carolina (248 [6.8%]), New York (237 [6.5%]), California (220 [6.0%]), and New Jersey (201 [5.5%]) together accounted for > 50% of all animal rabies cases reported in 2021. Of the total reported rabid animals, 3,352 (91.5%) involved wildlife, with bats (n = 1,241 [33.9%]), raccoons (1,030 [28.1%]), skunks (691 [18.9%]), and foxes (314 [8.6%]) representing the primary hosts confirmed with rabies. Rabid cats (216 [5.9%]), cattle (40 [1.1%]), and dogs (36 [1.0%]) accounted for 94% of rabies cases involving domestic animals in 2021. Five human rabies deaths were reported in 2021. CLINICAL RELEVANCE: The number of animal rabies cases reported in the US decreased significantly during 2021; this is thought to be due to factors related to the COVID-19 pandemic.

Rabies virus in white-nosed coatis (Nasua narica) in Mexico: what do we know so far?

Rabies is a neglected disease that affects all mammals. To determine the appropriate sanitary measures, the schedule of preventive medicine campaigns requires the proper identification of the variants of the virus circulating in the outbreaks, the species involved, and the interspecific and intraspecific virus movements. Urban rabies has been eradicated in developed countries and is being eradicated in some developing countries. In Europe and North America, oral vaccination programs for wildlife have been successful, whereas in Latin America, Asia, and Africa, rabies remains a public health problem due to the habitation of a wide variety of wild animal species that can act as rabies virus reservoirs in their environment. After obtaining recognition from the WHO/PAHO as the first country to eliminate human rabies transmitted by dogs, Mexico faces a new challenge: the control of rabies transmitted by wildlife to humans and domestic animals. In recent years, rabies outbreaks in the white-nosed coati (Nasua narica) have been detected, and it is suspected that the species plays a significant role in maintaining the wild cycle of rabies in the southeast of Mexico. In this study, we discussed cases of rabies in white-nosed coatis that were diagnosed at InDRE (in English: Institute of Epidemiological Diagnosis and Reference; in Spanish: Instituto de Diagnostico y Referencia Epidemiologicos) from 1993 to 2022. This study aimed to determine whether white-nosed coatis might be an emergent rabies reservoir in the country. A total of 13 samples were registered in the database from the Rabies laboratories of Estado de Mexico (n = 1), Jalisco (n = 1), Quintana Roo (n = 5), Sonora (n = 1), and Yucatan (n = 5). Samples from 1993 to 2002 from Estado de Mexico, Jalisco, and Sonora were not characterized because we no longer had any samples available. Nine samples were antigenically and genetically characterized. To date, coatis have not been considered important vectors of the rabies virus. The results from our research indicate that the surveillance of the rabies virus in coatis should be relevant to prevent human cases transmitted by this species.

The New Face of Human Rabies in Mexico, What's Next After Eradicating Rabies in Dogs.

In pre-Hispanic Mexico, dogs were not identified as an important source of rabies. We know from codexes and chronicles of the conquerors that at that time, rabies cases in humans and domestic animals were caused by local wildlife species such as bats. Canine-rabies virus variant seems to have arrived with Europeans. The first documented case of canine rabies in the Americas is found in Mexico in the Annals of the Holy Inquisition (16th century). During Mexico's independence, cases were frequently reported. In the 19th century the first attempts to control human rabies were made through sanitary measures such as elimination of rabid dogs and applying postexposure vaccination. During the first half of the 20th century, the efficacy of canine vaccination to prevent human rabies was established. However, in Mexico, despite reports of numerous human cases (>70/year), canine vaccination did not have enough coverage. It was only during the 1990s that Mexico made a serious commitment to eliminate dog-transmitted human rabies. Since the beginning, vaccination campaigns have been free and massive. Coverage increased from 7,100,000 doses in 1990 to more than 18,000,000 since 2017. This culminated in the elimination of dog-mediated human rabies cases since 2006. Subsequently, the epidemiology of rabies had changed. Nowadays, it is wildlife species (mainly bats and skunks) that are the source of human rabies. As a mega-biodiverse country Mexico has numerous wildlife species with potential to transmit rabies virus. Thus it is paramount to remain vigilant with respect to canine vaccination campaigns and to promote rabies research in wildlife.

Rabies surveillance in the United States during 2020.

OBJECTIVE: To provide epidemiological information on animal and human cases of rabies in the US during 2020 and summaries of 2020 rabies surveillance for Canada and Mexico. ANIMALS: All animals submitted for laboratory diagnosis of rabies in the US during 2020. PROCEDURES: State and territorial public health departments and USDA Wildlife Services provided 2020 rabies surveillance data. Data were analyzed temporally and geographically to assess trends in domestic and wildlife rabies cases. RESULTS: During 2020, 54 jurisdictions submitted 87,895 animal samples for rabies testing, of which 85,483 (97.3%) had a conclusive (positive or negative) test result. Of these, 4,479 (5.2%) tested positive for rabies, representing a 4.5% decrease from the 4,690 cases reported in 2019. Texas (n = 580 [12.9%]), Pennsylvania (371 [8.3%]), Virginia (351 [7.8%]), New York (346 [7.7%]), North Carolina (301 [6.7%]), New Jersey (257 [5.7%]), Maryland (256 [5.7%]), and California (248 [5.5%]) together accounted for > 60% of all animal rabies cases reported in 2020. Of the total reported rabid animals, 4,090 (91.3%) involved wildlife, with raccoons (n = 1,403 [31.3%]), bats (1,400 [31.3%]), skunks (846 [18.9%]), and foxes (338 [7.5%]) representing the primary hosts confirmed with rabies. Rabid cats (288 [6.4%]), cattle (43 [1.0%]), and dogs (37 [0.8%]) accounted for 95% of rabies cases involving domestic animals in 2020. No human rabies cases were reported in 2020. CONCLUSIONS AND CLINICAL RELEVANCE: For the first time since 2006, the number of samples submitted for rabies testing in the US was < 90,000; this is thought to be due to factors related to the COVID-19 pandemic, as similar decreases in sample submission were also reported by Canada and Mexico.

Rabies Virus Variants Detected from Cougar (Puma concolor) in Mexico 2000-2021.

In 2019, the World Health Organization (WHO) and the Pan-American Health Organization (PAHO) recognized Mexico as a country free of human rabies transmitted by dogs. Nevertheless, the sylvatic cycle remains as a public health concern in the country. Although cougars (Puma concolor) are not reservoirs of any rabies virus variant (RVV), these felines could act as vectors at the top of the food chain, and their relationships with other organisms must be considered important for the regulatory effect on their prey's populations. In this study, genetic and antigenic characterization was performed on all cougar rabies cases diagnosed at the Rabies Laboratory Network of the Ministry of Health (RLNMH) in Mexico from 2000 to 2021. Samples from other species, a skunk, a horse (Equus caballus) (attacked by a cougar), and a gray fox (Urocyon cineroargenteus), were included as reference. Rabies cases in cougars were restricted to two Northern states of Mexico (Sonora and Chihuahua). Five out of six samples of cougars were RVV7 (Arizona gray fox RVV) and one from Sonora was RVV1. Interestingly, there is no evidence of RVV1 in dogs in the Northern states since the 1990s but skunk species now harbor this RVV1 in this region of the country.

Biosafety Practices When Working with Bats: A Guide to Field Research Considerations.

Introduction: Field work with bats is an important contribution to many areas of research in environmental biology and ecology, as well as microbiology. Work with bats poses hazards such as bites and scratches, and the potential for exposure to infectious pathogens such as rabies virus. It also exposes researchers to many other potential hazards inherent to field work, such as environmental conditions, delayed emergency responses, or challenging work conditions. Methods: This article discusses the considerations for a thorough risk assessment process around field work with bats, pre- and post-occupational health considerations, and delves into specific considerations for areas related to biosafety concerns-training, personal protective equipment, safety consideration in field methods, decontamination, and waste. It also touches on related legal and ethical issues that sit outside the realm of biosafety, but which must be addressed during the planning process. Discussion: Although the focal point of this article is bat field work located in northern and central America, the principles and practices discussed here are applicable to bat work elsewhere, as well as to field work with other animal species, and should promote careful considerations of how to safely conduct field work to protect both researchers and animals.

Assessing the SARS-CoV-2 threat to wildlife: Potential risk to a broad range of mammals.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect animals, however, the whole range of potential hosts is still unknown. This work makes an assessment of wildlife susceptibility to SARS-CoV-2 by analyzing the similarities of Angiotensin Converting Enzyme 2 (ACE2) and Transmembrane Protease, Serine 2 (TMPRSS2)-both recognized as receptors and protease for coronavirus spike protein-and the genetic variation of the viral protein spike in the recognition sites. The sequences from different mammals, birds, reptiles, and amphibians, and the sequence from SARS-CoV-2 S protein were obtained from the GenBank. Comparisons of aligned sequences were made by selecting amino acids residues of ACE2, TMPRSS2 and S protein; phylogenetic trees were reconstructed using the same sequences. The species susceptibility was ranked by substituting the values of amino acid residues for both proteins. Our results ranked primates at the top, but surprisingly, just below are carnivores, cetaceans and wild rodents, showing a relatively high potential risk, as opposed to lab rodents that are typically mammals at lower risk. Most of the sequences from birds, reptiles and amphibians occupied the lowest ranges in the analyses. Models and phylogenetic trees outputs showed the species that are more prone to getting infected with SARS-CoV-2. Interestingly, during this short pandemic period, a high haplotypic variation was observed in the RBD of the viral S protein, suggesting new risks for other hosts. Our findings are consistent with other published results reporting laboratory and natural infections in different species. Finally, urgent measures of wildlife monitoring are needed regarding SARS-CoV-2, as well as measures for avoiding or limiting human contact with wildlife, and precautionary measures to protect wildlife workers and researchers; monitoring disposal of waste and sewage than can potentially affect the environment, and designing protocols for dealing with the outbreak.

Canine distemper in neotropical procyonids: Molecular evidence, humoral immune response and epidemiology.

Canine Distemper Virus (CDV) can produce a fatal multisystem disease in carnivores and other mammals and is an important threat for wildlife conservation. However, integrative and comparative studies in wild carnivores are scarce and some areas of the world lack of genetic studies. We explore the dynamic of host-CDV in a procyonid community during an outbreak. This study reports for the first time an index case occurred in a common raccoon (Procyon lotor) and for which a complete CDV diagnosis was performed. The long-term epidemiological analysis in two sympatric populations of common raccoons and white-nosed coatis (Nasua narica) was achieved through seroneutralization, RT-PCR and direct immunofluorescence assays. Additionally, hematologic analyses were performed and phylogenetic reconstruction of CDV was done using molecular data from this study. Overall prevalence for white-nosed coatis was 19.6 % and for common raccoons was 25.3 % by seroneutralization, and 13.3 % and 17.3 % by RT-PCR. Antibodies titer average for white-nosed coatis was 1:512 and 1:156 for common raccoons. Significant difference in prevalence between white-nosed coatis and common raccoons was detected during one season (summer 2013). White-nosed coatis showed differences in erythrocytes and monocytes counts between positives and negative animals. A 100 % similarity was found between CDV of white-nosed coati and CDV of common raccoon and is a new CDV sequence not previously described; this sequence is close to Asian and European lineage. An endemic state of distemper in both species was observed but showed different dynamics over time per host species. Differences in cellular and humoral responses were also detected between procyonids. The evidence found here may have serious implications for CDV understanding in wild carnivores, it reveals clear differences in the response over time to the same CDV strain, in two close related carnivore species.

Public Veterinary Medicine: Public Health Rabies virus variants identified in Nuevo Leon State, Mexico, from 2008 to 2015.

OBJECTIVE: To identify rabies virus variants (RVVs) isolated from bats and terrestrial mammals in Nuevo Leon between 2008 and 2015 and Coahuila in 2006. SAMPLE: RVVs isolated from 15 bats and terrestrial mammals in Nuevo Leon and from a cow (Bos taurus) in Coahuila, along with 46 reference rabies virus sequences. PROCEDURES: Antigenic characterization of the 16 isolates was performed with an indirect fluorescent antibody technique. Genomic sequencing of the nucleoprotein gene in the 16 isolates was performed with a reverse transcription PCR assay. Phylogenetic reconstruction of the 62 sequences was performed by means of Bayesian inference. RESULTS: 9 isolates from bats and 1 isolate from a domestic cat that became infected as a result of contact with a Mexican free-tailed bat all clustered in the lineage associated with Lasiurus spp in the Americas or the lineage associated with Tadarida brasiliensis mexicana. An isolate from a domestic dog was identified as a variant associated with the dog-coyote lineage. The RVV isolated from a fox clustered in an Arizona fox lineage. The 3 RVVs from skunks (Mephitis macroura) were placed in a lineage with variants isolated from spotted skunks (Spilogale putorius). The RVV isolated from the cow was clustered in a lineage associated with foxes in Texas and separate from the lineage for the fox from Nuevo Leon. CONCLUSIONS AND CLINICAL RELEVANCE: Results reinforced the need for Mexico to implement rabies surveillance and monitoring programs for bats and wild-living terrestrial carnivores.

Litomosoides sp. (Filarioidea: Onchocercidae) Infection in Frugivorous Bats (Artibeus spp.): Pathological Features, Molecular Evidence, and Prevalence.

Bats can host pathogenic organisms such as viruses and fungi, but little is known about the pathogenicity of their parasites. Hemoparasites are frequently recorded in Neotropical bats, particularly Litomosoides (Filarioidea: Onchocercidae), but their pathogenic effect on bats is scarcely known. In this work, Litomosoides microfilariae were identified in four (8%) out of 51 sampled frugivorous bats belonging to three different species: Artibeus aztecus, Artibeus jamaicensis, and Artibeus lituratus, which are located in Yautepec, Morelos, Mexico. Two infected animals showed weakness, tachypnoea, and ecchymosis on their wings. In these animals, histopathology revealed microfilariae in the blood vessels of the lung, liver, and spleen. Both animals presented exudative pneumonia with congestion and concomitant edema, in addition to moderate arterial hypertrophy. Parasitemia was quantified in blood samples of the infected animals (>3000 parasites/mL). Phylogenetic analysis placed the obtained sequence inside the Litomosoides genus, reaching over 98% identity to the related species. Due to the relevance of bats in ecosystems, any new record of their parasite repertoire offers noteworthy insights into our understanding of the ecology and impact of new parasite species in bats.

Detection of Bartonella species, including Candidatus Bartonella ovis sp. nov, in ruminants from Mexico and lack of evidence of Bartonella DNA in saliva of common vampire bats (Desmodus rotundus) predating on them.

Bartonella spp. have been identified in many bat species worldwide, including the zoonotic species, Candidatus Bartonella mayotimonensis. The common vampire bat (Desmodus rotundus) preys preferentially on livestock in Latin America and is frequently infected with Bartonella spp. To determine the potential role of D. rotundus in transmitting Bartonella to livestock, common vampire bats and bat-bitten domestic ruminants from Mexico were tested for Bartonella infection by blood culture or conventional PCR. Furthermore, to explore the possibility of bite transmission during blood feeding, saliva swabs from 35 D. rotundus known to be either Bartonella bacteremic (N = 17) or blood culture negative (N = 18) were tested by PCR to detect the presence of Bartonella DNA. Twenty (17.1%) of 117 sheep and 16 (34.8%) of 46 cattle were Bartonella bacteremic by PCR testing. However, none of them were infected with Bartonella strains previously isolated from vampire bats and none of the 35 D. rotundus saliva swabs tested were PCR positive for Bartonella. All but two animals among those which were Bartonella culture and/or PCR positive, were infected with either B. bovis (cattle) or B. melophagi (sheep). Two sheep were infected by a possible new species, Candidatus Bartonella ovis, being phylogenetically closer to B. bovis than B. melophagi. This study does not support the role of D. rotundus as a reservoir of Bartonella species infecting livestock, which could be transmitted via bite and blood feeding and therefore suggest limited risk of zoonotic transmission of Bartonella from common vampire bats to humans.