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Bats are important natural reservoir hosts of a diverse range of viruses that can be transmitted to humans and have been suggested to play an important role in the Zika virus (ZIKV) transmission cycle. However, the exact role of these animals as reservoirs for flaviviruses is still controversial. To further expand our understanding of the role of bats in the ZIKV transmission cycle in Latin America, we carried out an experimental infection in wild-caught Artibeus lituratus bats and sampled several free-living neotropical bats across three countries of the region. Experimental ZIKV infection was performed in wild-caught adult bats (4 females and 5 males). The most relevant findings were hemorrhages in the bladder, stomach and patagium. Significant histological findings included inflammatory infiltrate consisting of a predominance of neutrophils and lymphocytes, in addition to degeneration in the reproductive tract of males and females. This suggests that bat reproduction might be at some level affected by ZIKV. Leukopenia was also observed in some inoculated animals. Hemorrhages, genital alterations, and leukopenia are suggested to be caused by ZIKV; however, since these were wild-caught bats, we cannot exclude other agents. Detection of ZIKV by qPCR was observed at low concentrations in only two urine samples in two inoculated animals. All other animals and tissues tested were negative. Finally, no virus-neutralizing antibodies were found in any animal. To determine ZIKV infection in nature, the blood of a total of 2056 bats was sampled for ZIKV detection by qPCR. Most of the sampled individuals belonged to the genus Pteronotus sp. (23%), followed by the species Carollia sp. (17%), Anoura sp. (14%), and Molossus sp. (13.7%). No sample of any tested species was positive for ZIKV by qPCR. These results together suggest that bats are not efficient amplifiers or reservoirs of ZIKV and may not have an important role in ZIKV transmission dynamics. Author summary: In previous works in 2008–2009, we found the presence of antibodies against flaviviruses, and viral RNA was detected in Neotropical chiropterans in Mexico, which led us to support the hypothesis that these animals could be reservoirs of flaviviruses. As controversial opinions have been exposed and based on a previous (2019) experimental ZIKV infection experiment conducted at Colorado State University using adult Artibeus males from a captive colony, in this work, we also experimentally infected adult Artibeus males complementarily adding females and using wild-caught animals instead of laboratory bats. We also monitored a diverse range of natural bat populations in Latin America for the presence of viral RNA against ZIKV in blood. A plaque reduction seroneutralization test was used for the detection of antibodies against ZIKV. Similar to the previous work, we found histopathological alterations in male testicles but also in the ovaries and oviducts of females, as well as gliosis and multifocal necrosis in pyramidal neurons and Purkinge cells of inoculated animals. Only two urine samples from inoculated animals showed viral RNA. Additionally, leukopenia and lymphoid follicular splenic hyperplasia were evidenced. In contrast to what was reported, no neutralizing antibodies against ZIKV were detected in any sample. Viral RNA within the blood was not present in any of the 2056 bat samples collected in French Guiana, Peru and Costa Rica and proceeding from 34 bat genera. These results together suggest that bats are not efficient amplifiers or reservoirs of ZIKV and might not have an important role in ZIKV transmission dynamics. [ABSTRACT FROM AUTHOR]

In humans, co‐infection of hepatitis B and C viruses (HBV, HCV) is common and aggravates disease outcome. Infection‐mediated disease aggravation is poorly understood, partly due to lack of suitable animal models. Carnivores are understudied for hepatitis virus homologues. We investigated Mexican carnivores (ringtails, Bassariscus astutus) for HBV and HCV homologues. Three out of eight animals were infected with a divergent HBV termed ringtail HBV (RtHBV) at high viral loads of 5 × 109 –1.4 × 1010 copies/ml serum. Two of the RtHBV‐infected animals were co‐infected with a divergent hepacivirus termed ringtail hepacivirus (RtHV) at 4 × 106–7.5 × 107 copies/ml in strain‐specific qRT‐PCR assays. Immunofluorescence assays relying on HBV core and RtHV NS3/4a proteins indicated that none of the animals had detectable hepadnavirus core‐specific antibodies, whereas one RtHV‐infected animal had concomitant RtHV‐specific antibodies at 1:800 end‐point titre. RtHBV and RtHV complete genomes showed typical HBV and HCV structure and length. All RtHBV genomes were identical, whereas RtHV genomes showed four amino acid substitutions located predominantly in the E1/E2‐encoding genomic regions. Both RtHBV (>28% genomic nucleotide sequence distance) and RtHV (>30% partial NS3/NS5B amino acid sequence distance) formed new species within their virus families. Evolutionary analyses showed that RtHBV grouped with HBV homologues from different laurasiatherian hosts (carnivores, bats, and ungulates), whereas RtHV grouped predominantly with rodent‐borne viruses. Ancestral state reconstructions showed that RtHV, but not RtHBV, likely emerged via a non‐recent host switch involving rodent‐borne hepacivirus ancestors. Conserved hepatitis virus infection patterns in naturally infected ringtails indicate that carnivores may be promising animal models to understand HBV/HCV co‐infection. [ABSTRACT FROM AUTHOR]

Background: Fluoroscopic‐guided lumbar procedures have increased in daily pain practice because the lumbar spine is one of the most common sources of pain. Interventional pain fellows must develop a minimum number of skills during their training in order to achieve the competences without neglecting radiological safety. However, medical training in fluoroscopic‐guided interventions is being affected by the current coronavirus disease 2019 (COVID‐19) situation. Methods: The objective of this study was to evaluate the use of a phantom model for lumbar injection as a training strategy during the COVID‐19 pandemic in fellows of interventional pain. The study was divided into theoretical and practical modules. The hands‐on practice was performed in a lumbar model phantom where fellows were evaluated in four fluoroscopically guided approaches: intra‐articular facet block (IAFB), medial branch block (MBB), transforaminal block (TFB), and interlaminar block (ILB) divided in 5 sessions. The aim was to make as many punctures as possible in every session. We measured total procedural performance (TPP), total needle hand time (TNH), and total radiation dose generated by the fluoroscopic machine (TRD) during each procedure. Additionally, a survey was applied to evaluate confidence and satisfaction before and after training. Results: A total of 320 lumbar punctures were completed. The results were statistically significant in all approaches attempted (p < 0.01). The fellow's survey for satisfaction and confidence demonstrated a significant difference between pre and post‐test (p < 0.01). Conclusions: The results of this study highlight the importance of adaptations and adoption of new educational models. The use of the phantom model for simulation could be a strategy for other emerging situations, like the COVID‐19 pandemic. Including this practice in the interventional pain programs could lead to better results for the patient and operator radiology safety. [ABSTRACT FROM AUTHOR]

Bartonellae are emerging blood-borne bacteria that have been recovered from a wide range of mammalian species and arthropod vectors around the world. Bats are now recognized as a potential wildlife reservoir for a diverse number of Bartonella species, including the zoonotic Candidatus B. mayotimonensis. These bat-borne Bartonella species have also been detected in the obligate ectoparasites of bats, such as blood-feeding flies, which could transmit these bacteria within bat populations. To better understand this potential for transmission, we investigated the relatedness between Bartonella detected or isolated from bat hosts sampled in Mexico and their ectoparasites. Bartonella spp. were identified in bat flies collected on two bat species, with the highest prevalence in Trichobius parasiticus and Strebla wiedemanni collected from common vampire bats (Desmodus rotundus). When comparing Bartonella sequences from a fragment of the citrate synthase gene (gltA), vector-associated strains were diverse and generally close to, but distinct from, those recovered from their bacteremic bat hosts in Mexico. Complete Bartonella sequence concordance was observed in only one bat-vector pair. The diversity of Bartonella strains in bat flies reflects the frequent host switch by bat flies, as they usually do not live permanently on their bat host. It may also suggest a possible endosymbiotic relationship with these vectors for some of the Bartonella species carried by bat flies, whereas others could have a mammalian host. [ABSTRACT FROM AUTHOR]

Blood-feeding arthropods play a major role in the transmission of several flaviviruses, which represent an important problem for human health. Currently, dengue is one of the most important arboviral emerging diseases worldwide. Furthermore, some previous studies have reported the presence of viral nucleic acids and antibodies against dengue virus (DENV) in wild animals. Our knowledge of the role played by wildlife reservoirs in the sylvatic transmission and maintenance of DENV remains limited. Our objective was to screen blood-feeding ectoparasites (bat flies) and their common vampire bat ( Desmodus rotundus) hosts, for flaviviruses in Hidalgo, Mexico. We detected Flavivirus sequences in 38 pools of ectoparasites (Diptera: Streblidae, Strebla wiedemanni and Trichobius parasiticus) and 8 tissue samples of D. rotundus by RT-PCR and semi-nested PCR using FlaviPF1S, FlaviPR2bis, and FlaviPF3S primers specific for NS5, a gene highly conserved among flaviviruses. Phylogenetic inference analysis performed using the maximum likelihood algorithm implemented in PhyML showed that six sequences clustered with DENV (bootstrap value = 53.5%). Although this study supports other reports of DENV detection in bats and arthropods other than Aedes mosquitoes, the role of these ectoparasitic flies and of hematophagous bats in the epidemiology of DENV still warrants further investigation. [ABSTRACT FROM AUTHOR]

The longhorned tick Haemaphysalis longicornis is a highly invasive tick that is native to Asia. Since its detection in New Jersey in 2017, this tick has spread to 18 states in the Northeast, the Midwest, and the Southeast regions of the United States. In Mexico, H. longicornis has been detected only once in an imported horse at the inspection point in Piedras Negras, Coahuila. However, the risk of introduction and establishment of this tick species is high due to importation of live animals, the frequent legal transportation of numerous pets by tourists, the migration of wildlife across the extensive northern border that is more than 3,000 km long, and the inherent difficulty in detecting immatures stages on animals. The aim of this work is to provide Spanish-language information on the distribution of H. longicornis in North America, as well as the ecological and biological aspects of this tick. This work includes morphological images of H. longicornis aimed at facilitating its accurate identification. This effort provides useful information for veterinarians, government agency officials, and other professionals involved in animal health and tick control to aid in the effective prevention of the introduction and establishment of H. longicornis in Mexico. [ABSTRACT FROM AUTHOR]