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Viruses in the subfamily Serpentovirinae (order Nidovirales , family Tobaniviridae ) can cause significant morbidity and mortality in captive snakes, but documented infections have been limited to snakes of the Boidae , Colubridae , Homalopsidae , and Pythonidae families. Infections can either be subclinical or associated with oral and/or respiratory disease. Beginning in June 2019, a population of over 150 confiscated snakes was screened for serpentovirus as part of a quarantine disease investigation. Antemortem oropharyngeal swabs or lung tissue collected postmortem were screened for serpentovirus by PCR, and 92/165 (56.0%) of snakes tested were positive for serpentovirus. Serpentoviruses were detected in fourteen species of Viperidae native to Asia, Africa, and South America and a single species of Elapidae native to Australia. When present, clinical signs included thin body condition, abnormal behavior or breathing, stomatitis, and/or mortality. Postmortem findings included variably severe inflammation, necrosis, and/or epithelial proliferation throughout the respiratory and upper gastrointestinal tracts. Genetic characterization of the detected serpentoviruses identified four unique viral clades phylogenetically distinct from recognized serpentovirus genera. Pairwise uncorrected distance analysis supported the phylogenetic analysis and indicated that the viper serpentoviruses likely represent the first members of a novel genus in the subfamily Serpentovirinae . The reported findings represent the first documentation of serpentoviruses in venomous snakes ( Viperidae and Elapidae ), greatly expanding the susceptible host range for these viruses and highlighting the importance of serpentovirus screening in all captive snake populations.

We present the complete genome sequences of Caribbean watersnake bornavirus (CWBV) and Mexican black-tailed rattlesnake bornavirus (MRBV), which we identified in archived raw transcriptomic read data of a Caribbean watersnake (Tretanorhinus variabilis) and a Mexican black-tailed rattlesnake (Crotalus molossus nigrescens), respectively. The genomes of CWBV and MRBV have a length of about 8,900 nucleotides and comprise the complete coding regions and the untranslated regions. The overall genomic makeup and predicted gene content is typical for members of the genus Orthobornavirus within the family Bornaviridae. Alternative splicing was detected for the L and M genes. Based on a phylogenetic analysis of all viral proteins, we consider both viruses to be members of a single novel species within the genus Orthobornavirus. Both viruses form a distinct outgroup to all currently known orthobornaviruses. Based on the novel virus genomes, we furthermore identified closely related endogenous bornavirus-like nucleoprotein sequences in transcriptomic data of veiled chameleons (Chamaeleo calyptratus) and a common lancehead (Bothrops atrox)., (© 2021. The Author(s).)

Ferlaviruses (FV, previously referred to as ophidian paramyxoviruses, OPMV), are enveloped viruses with a negative-strand RNA genome, affecting snakes in captivity worldwide. Infection is characterized by respiratory and nervous clinical signs and carries high mortality rates, but no specific treatment or vaccine is currently available. Costa Rica has 16 species of vipers, found in captivity in collections essential for antivenom production, reintroduction, and public education. FV circulation in these populations was previously unknown, and the risk of introducing the viruses into naïve collections or free-ranging populations exists if the virus's presence is confirmed. The objective of this study was to determine seroprevalence and FV shedding in 150 samples from captive vipers in nine collections across Costa Rica. A hemagglutination inhibition (HI) assay was performed to determine the antibody titer against two Ferlavirus strains, Bush viper virus (BV) and Neotropical virus (NT), and reverse-transcriptase polymerase chain reaction (RT-PCR) and sequencing to determine virus secretion in cloacal swabs. Ferlavirus strains were replicated in Vero cells, and chicken anti-FV polyclonal antibodies were produced and used as a positive control serum for the HI. Results demonstrate that seroprevalence of anti-FV antibodies in viper serum was 26.6% (n = 40) for the BV strain and 30% (n = 45) for the NT strain in the population tested. Furthermore, molecular characterization of FV group A was possible by sequencing the virus recovered from three cloacal swabs, demonstrating circulation of FV in one collection. This study demonstrates for the first time serological evidence of FV exposure and infection in vipers in captivity in Costa Rica, and suggests cross reactivity between antibodies against both strains. Appropriate biosafety measures could prevent the spread of FV between and within collections of reptiles in the country.

Sixteen captive adult horned vipers (Vipera ammodytes ammodytes) were submitted for necropsy examination following a 2-week history of lethargy, anorexia and dyspnoea. Gross lesions included widespread haemorrhage, serosanguineous effusions in the body cavities and multiple pinpoint white to yellow foci in the liver. Microscopically, there was multifocal hepatic coagulative necrosis associated with intranuclear acidophilic inclusion bodies in sinusoidal endothelial cells. Similar endothelial lesions were observed in the myocardium, fat bodies, kidneys and spleen. Transmission electron microscopy revealed numerous virions (100-110 nm) in the nuclei of endothelial cells and intracytoplasmic enveloped virions (140-150 nm) were also found. The gross and histological findings and the ultrastructural features of the intranuclear inclusions and viral particles were consistent with herpesviral infection. To the best of our knowledge, these are the first reported cases of a lethal herpesvirosis in horned vipers and the second report in snakes., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

In this study, we sequenced the whole genome of a reovirus isolated from a green bush viper (Atheris squamigera). The bush viper reovirus shared several features with other orthoreoviruses, including its genome organization. In phylogenetic analysis, this strain was monophyletic with Broome virus and baboon orthoreovirus, indicating that these viruses might have originated from a common ancestor. These new molecular data supplement previous information based mainly on biological properties of reptilian reoviruses, confirming their taxonomic position and broadening our knowledge of the evolution of members of the genus Orthoreovirus.

The objective was to study Orthomyxovirus in heterothermic animals. Blood samples from snakes (genus Bothrops and Crotalus) and from toads and frogs (genus Bufo and Rana) were collected to evaluate the red cell receptors and antibodies specific to influenza virus by the hemagglutination and hemagglutination inhibition tests, respectively. Both snakes and toads kept in captivity presented receptors in their red cells and antibodies specific to either influenza virus type A (human and equine origin) or influenza type B. The same was observed with recently captured snakes. Concerning the influenza hemagglutination inhibition antibodies protective levels were observed in the reptiles' serum, against influenza type A and type B. Unlike the toads, 83.3% of the frogs presented mean levels of Ab 40HIU for some influenza strains. It was concluded that heterothermic animals could offer host conditions to the influenza virus and also susceptibility to the infection.

Two reptilian paramyxoviruses, isolated from a neotropical rattlesnake (neotropical virus, NTV, ATCC VR-1408) and a bush viper (bush viper virus, BVV, ATCC VR- 1409), respectively, were analysed to determine their taxonomic position among other reptilian paramyxoviruses investigated previously by Ahne et al.. A 679 bp long region of the hemagglutinin-neuraminidase (HN) gene and a 627 bp long region of the large (L) gene were reverse transcribed, amplified by polymerase chain reaction (PCR), and sequenced. The deduced amino acid sequences were compared to mammalian paramyxoviruses belonging to the genera Respirovirus and Rubulavirus. The deduced amino acid sequences revealed 58.9 to 62% homology for the partial L protein and 41% to 47.1% homology for the partial HN protein. For phylogenetic analyses, a 518 bp L gene and a 352 bp HN gene fragment were used, both generating similar trees consisting of two distinct main groups, and some intermediate isolates. BVV clustered within group "b" while NTV clustered together with the intermediate ophidian paramyxovirus isolate Crot2-OH90.

Multiple epizootics of pneumonia in captive snakes have been attributed to viruses which have been tentatively placed in the family Paramyxoviridae. Viruses isolated from an ill Neotropical rattlesnake (Crotalus durissus terrificus), from an Aruba Island rattlesnake (Crotalus unicolor), and from a bush viper (Atheris sp.) were propagated in Vero cells and characterized. Viral particles produced in Vero cells were pleomorphic, enveloped, and contained helical nucleocapsids. The viruses were sensitive to ether and to acidic and basic pH. Moreover, they had neuraminidase activity and were able to agglutinate erythrocytes from chicken and a variety of species of mammals. Hemagglutination was inhibited with rabbit antiserum raised against each virus. The buoyant densities of the three isolates ranged from 1.13/cm3 to 1.18/cm3, values consistent with that for an enveloped virus. The nucleic acid in the virion was determined to be RNA by [3H]uridine incorporation. Viral proteins characteristic of paramyxoviruses were immunoprecipitated from cells infected with each of the three isolates using rabbit anti-Neotropical virus serum. The morphologic appearance, physico- and biochemical properties, and cytopathologic effects of these snake viruses were consistent with those of certain members of the family Paramyxoviridae.