Spatio-temporal trends and risk factors affecting West Nile virus and related flavivirus exposure in Spanish wild ruminants.

BACKGROUND: During the last decade, the spread of many flaviviruses (Genus Flavivirus) has been reported, representing an emerging threat for both animal and human health. To further study utility of wild ruminant samples in West Nile virus (WNV) surveillance, we assessed spatio-temporal trends and factors associated with WNV and cross-reacting flaviviruses exposure, particularly Usutu virus (USUV) and Meaban virus (MBV), in wild ruminants in Spain. Serum samples from 4693 wild ruminants, including 3073 free-living red deer (Cervus elaphus), 201 fallow deer (Dama dama), 125 mouflon (Ovis aries musimon), 32 roe deer (Capreolus capreolus) and 1262 farmed red deer collected in 2003-2014, were screened for WNV and antigenically-related flavivirus antibodies using a blocking ELISA (bELISA). Positive samples were tested for neutralizing antibodies against WNV, USUV and MBV by virus micro-neutralization tests. RESULTS: Mean flavivirus seroprevalence according to bELISA was 3.4 ± 0.5 % in red deer, 1.0 ± 1.4 % in fallow deer, 2.4 ± 2.7 % in mouflon and 0 % in roe deer. A multivariate logistic regression model revealed as main risk factors for seropositivity in red deer; year (2011), the specific south-coastal bioregion (bioregion 5) and presence of wetlands. Red deer had neutralizing antibodies against WNV, USUV and MBV. CONCLUSIONS: The results indicate endemic circulation of WNV, USUV and MBV in Spanish red deer, even in areas without known flavivirus outbreaks. WNV antibodies detected in a free-living red deer yearling sampled in 2010, confirmed circulation this year. Co-circulation of WNV and USUV was detected in bioregions 3 and 5, and of WNV and MBV in bioregion 3. Sampling of hunted and farmed wild ruminants, specifically of red deer yearlings, could be a complementary way to national surveillance programs to monitor the activity of emerging flaviviruses.

Exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the endangered Iberian lynx (Lynx pardinus).

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging zoonotic virus of public and animal health concern, of which felids have been suggested as potential reservoirs. Although SARS-CoV-2 exposure has been detected in domestic and wild captive animals belonging to Felidae family, surveillance has not been carried out in free-ranging wild felids so far. The aim of the present study was to assess SARS-CoV-2 exposure in the Iberian lynx (Lynx pardinus), the most endangered felid in the world. Between 2019 and 2022, we conducted a seroepidemiological study of SARS-CoV-2 in 276 free-ranging and captive Iberian lynxes. Our results evidenced limited (0.4%; 95%CI: 0.0-1.1) but not negligible exposure to this emerging virus in this endangered felid species, increasing the SARS-CoV-2 host range. The circulation of this virus in wildlife evidences the need of integrated European wildlife monitoring.

Monitoring the dynamics of consumption of ungulate game by-products in vulture feeding stations in Iberian Mediterranean ecosystems.

Vulture feeding stations (VFS) are strategic sites for the management of ungulate game by-products, with major implications for the conservation of obligate avian scavengers. These feeding points are designed to prevent access by facultative mammalian scavengers and to reduce the risk of trophically transmitted pathogen infection through scavenging behaviour. The aim of this study, using camera trap video recordings, was to evaluate the feeding dynamics around 32 lots of ungulate game by-products deposited in VFS in southern Spain. During the study period (2017-2022), 11 different avian and mammal scavenger species was detected. Also, many feeding events involving all scavenger species (51.1%; 362/709) and mammal scavenger species (23.4%; 166/709) was recorded. A significantly earlier presence of major obligate scavengers (Gyps fulvus and Aegypius monachus) (P = 0.023) and a lower persistence of by-products deposited (P < 0.001) were detected during October-December compared to January-March. Our results confirm that VFS play an important role in vulture conservation in Iberian Mediterranean ecosystems. However, we also point out the potential risk of VFS as hotspots of foodborne pathogens for mammal scavengers, particularly when the hunting offal persists longer. Consequently, we urge the competent authorities to update the regulations affecting VFS management, and hunting estate managers to make every effort to correctly apply those preventing scavenging mammals from gaining access to VFS. Further studies tackling access of non-target species to VFS are also warranted to properly assess the sanitary implications and geographical extent of these problems for mammal species inhabiting areas where VFS are installed.

Molecular detection of Rickettsia spp. in wild ungulates and their ticks in Mediterranean areas of southwestern Spain.

Wildlife is an important reservoir of zoonotic pathogens. The objective of the present study was to assess the importance of wild ungulates in the epidemiology of Rickettsia spp. Ticks and spleen samples were collected from 262 red deer (Cervus elaphus) and 83 wild boar (Sus scrofa) hunted in southwestern Spain over a 5-year period. DNA was extracted from tick pools (n = 191) and spleens (n = 345), and two nested PCR assays targeting the rOmpA and rOmpB genes were used to detect Rickettsia DNA. Five tick species were identified (Hyalomma lusitanicum, Dermacentor marginatus, Ixodes ricinus, Rhipicephalus bursa and Haemaphysalis sulcata). Rickettsia DNA was detected in 31 (16.2%) tick pools and two red deer spleen samples (0.8%). Four validated Rickettsia species (R. slovaca, R. monacensis, R. helvetica and R. raoultii), one uncultivated species (Candidatus R. rioja) and two uncharacterized Rickettsia spp. were detected in ticks. R. helvetica and R. slovaca were also detected in spleen samples from red deer. The overall prevalence in ungulate spleen samples was lower than in tick pools suggesting that these ungulates do not play a major role in the transmission of Rickettsia spp. However, their importance as spreaders of positive ticks cannot be ruled out. The results present a challenge for the veterinary and public health communities since most of the Rickettsia spp. detected are pathogenic. Furthermore, the new Rickettsia species could be potential pathogens. For these reasons, identifying Rickettsia species present in ticks and wildlife is of particular interest to clarify their sylvatic cycle and establish appropriate control measures.

Prevalence of selected tick-borne pathogens in wild ungulates and ticks in southern Spain.

A survey study was carried out to assess the occurrence of selected tick-borne pathogens (TBP) in wild ungulates in Mediterranean ecosystems in southern Spain. Spleen samples were collected from 1,132 wild ungulates, including 578 red deer, 269 wild boar, 135 mouflon, 121 fallow deer and 29 roe deer, between 2009 and 2015. Eighty-nine ticks collected from TBP-positive animals were also analysed. Samples were tested by PCR and sequenced whenever possible. TBP DNA was detected in 127 of 863 wild ruminants (14.7%; 95% CI: 12.4-17.3) including the following: Anaplasma phagocytophilum (9.2%), Babesia divergens (2.9%), Theileria sp. OT3 (1.7%), Borrelia afzelii (0.7%) and Theileria capreoli (0.2%), but no positive samples were detected in wild boar (0/269). All the strains from mouflon were identified as Theileria sp. OT3, while B. divergens and T. capreoli were mainly found in red deer. Co-infection with A. phagocytophilum and B. divergens, and A. phagocytophilum and Theileria spp. was detected in red deer and mouflon, respectively. The risk factor analysis showed that the prevalences of A. phagocytophilum and piroplasms were species-related. Eighty-nine tick specimens collected from ungulates found to be infected with the selected TBP were identified as Hyalomma lusitanicum (95.5%) and Ixodes ricinus (4.5%). Thirty ticks were positive for Anaplasma/Ehrlichia spp. (33.7%), 25 for Babesia/Theileria (28.1%) and two for B. burgdorferi s.l. (2.3%). Eleven specimens showed co-infections with Anaplasma/Ehrlichia and Babesia/Theileria (10.1%) or Anaplasma/Ehrlichia and B. burgdorferi s.l. (2.3%). The estimated prevalences obtained in the present study suggest the possible contribution of wild ruminants to the maintenance of some selected TBP in Mediterranean ecosystems in southern Spain, while the role of wild boar in the epidemiology of these pathogens seems to be limited in this region.

Hepatitis E virus in the endangered Iberian lynx (Lynx pardinus).

Hepatitis E virus (HEV) is an emerging zoonotic pathogen in Europe. In the Iberian Peninsula, wild boar (Sus scrofa) is considered the main wildlife reservoir of HEV. This wild ungulate shares habitat and resources with other potential HEV carriers in Iberian Mediterranean ecosystems, although information about the role of such sympatric species in the HEV epidemiological cycle is still very limited. The aims of the present large-scale, long-term study were: (1) to determine the seroprevalence and prevalence of HEV in both free-living and captive populations of the Iberian lynx (Lynx pardinus), the most endangered felid in the world; (2) to determine potential risk factors associated with HEV exposure in this species and (3) to evaluate the dynamics of seropositivity in longitudinally sampled animals during the study period. Between 2010 and 2021, serum samples from 275 Iberian lynxes were collected in free-ranging and captive populations across the Iberian Peninsula. Forty-four of the 275 lynxes were also longitudinally sampled during the study period. A double-antigen sandwich ELISA was used to test for the presence of antibodies against HEV. A subset of seropositive samples was analysed by Western blot (WB) assay to confirm exposure to HEV. In addition, serum, liver and/or faecal samples from 367 individuals were tested for orthohepevirus RNA by RT-PCR. A total of 50 (18.2%; 95% CI: 14.1-23.2) of the 275 animals analysed had anti-HEV antibodies by ELISA. Exposure to HEV was confirmed by WB in most of the ELISA-positive Iberian lynxes analysed. Significantly higher seroprevalence was found in captive (33.6%) compared to free-ranging (7.4%) individuals. Within captive population, the GEE model identified 'age' (senile, adult and subadult) as risk a factor potentially associated with HEV exposure in the Iberian lynx. Thirteen (29.5%) of 44 longitudinally surveyed individuals seroconverted against HEV during the study period. HEV RNA was detected in the faeces of one (1/364; 0.3%; 95% CI: 0.0-0.8) free-ranging adult animal sampled in 2021. Phylogenetic analysis showed that the sequenced strain belongs to HEV-3f subtype and shared a high nucleotide sequence identity (97-99.6%) with human HEV-3f sequences from Spain and France. To the best of the authors' knowledge, this is the first survey study on HEV in the Iberian lynx and the first molecular report of HEV-A infection in free-ranging felines. Our results indicate high exposure to HEV-3 in Iberian lynx populations, particularly those kept in captivity. The serological results suggest widespread but not homogeneous circulation of HEV in Iberian lynx populations. Further studies are required to assess the epidemiological role of this endangered species as a potential spillover host of HEV.

Seroprevalence and risk factors of Toxoplasma gondii infection in wild ungulates that cohabit in a natural park with human-animal interaction in the Mediterranean ecosystem.

The possibility of Toxoplasma gondii transmitted from game meat to humans is of public health concern. Here we determined seroprevalence and risk factors associated with T. gondii in large game ungulates that cohabit in Sierras de Cazorla, Segura and Las Villas Natural Park (SCSV-NP) (Southern Spain), a natural park with high human-animal interaction. Antibodies against T. gondii in 328 wild ungulates were assayed by the modified agglutination test (MAT ≥ 1:25). Antibodies were found in 39 (11.9%, 95% CI: 8.4-15.4) wild ungulates, with seroprevalence levels of 20.8% in wild boars (Sus scrofa) (5/24), 19.0% in fallow deer (Dama dama) (12/63), 13.9% in Iberian ibex (Capra pyrenaica hispanica) (14/101), 7.9% in red deer (Cervus elaphus) (6/76), and 3.1% in mouflons (Ovis aries musimon) (2/64). Significantly higher seroprevalence was observed in fallow deer and wild boars compared to mouflons. Animals living close to urban areas (<2 km) had 4.6-times higher risk compared to those living at >5 km of urban areas. The results indicate high circulation of T. gondii in wild ungulates in SCSV-NP, which is of animal and public health concern. The increased seroprevalence of T. gondii detected in wildlife ungulates living close to urban areas may increase human infection in those areas if meat from infected animals is consumed raw or undercooked.

Boundary-Condition Analysis of an Idealized Left Atrium Model.

The most common type of cardiac arrhythmia is atrial fibrillation (AF), which is characterised by irregular and ineffective atrial contraction. This behaviour results into the formation of thrombi, mainly in the left atrial appendage (LAA), responsible for thromboembolic events. Very different approaches are considered as therapy for AF patients. Therefore, it is necessary to yield insight into the flow physics of thrombi formation to determine which is the most appropriate strategy in each case. Computational Fluid Dynamics (CFD) has proven successful in getting a better understanding of the thrombosis phenomenon, but it still requires validation by means of accurate flow field in vivo atrial measurements. As an alternative, in this paper it is proposed an in vitro flow validation, consisting in an idealised model that captures the main flow features observed in the human LA which, once combined with Particle Image Velocimetry (PIV) measurements, provides readily accessible, easy to emulate, detailed velocity fields. These results have been used to validate our laminar and Large Eddy Simulation (LES) simulations. Besides, we have run a parametric study of different boundary conditions sets previously employed in the literature. These data can be used as a benchmark for further development of LA CFD models.

Serosurvey of Peste des Petits Ruminants in southern Spain.

Peste des Petits Ruminants (PPR) is a highly infectious disease caused by a virus member of the genus Morbillivirus, which mainly affects goats, sheep and wild ruminants. It is considered one of the most significant transboundary infectious diseases and represents an animal health concern in developing countries. Spain is considered a PPR-free country. Nevertheless, given its geographical proximity to countries in North Africa where PPR virus (PPRV) has been circulating in recent years, the south of Spain can be considered a risk area for the introduction of PPRV. The aim of the present study was to assess circulation of PPRV in domestic and wild ruminant species in this country. During the period 2015-2017, a total of 910 sera from domestic, wild and captive ruminants were analysed using a commercial blocking ELISA to detect antibodies against PPRV. None of the 910 (0.0%; 95% CI: 0.0-0.3) animals tested were positive for anti-PPRV antibodies. To the best of our knowledge, this is the first serosurvey study of PPR in Spain. The results indicate absence of circulating PPRV in the south of Spain during the study period. Due to the risk of PPRV introduction into European countries of the Mediterranean basin, epidemiological surveillance should be maintained and extended in this region.

Description of the first Schmallenberg disease outbreak in Spain and subsequent virus spreading in domestic ruminants.

Schmallenberg disease (SBD) is an emerging disease transmitted mainly among ruminant species by biting midges of the genus Culicoides. Since the Schmallenberg virus (SBV) was first identified in Germany in late 2011, it rapidly spread to other European countries. The aims of the present study were to describe the first SBD outbreak in Spain and to assess the spread and risk factors associated with SBV infection in domestic ruminants from nearby farms during the following year. In March 2012, one malformed stillborn lamb from a sheep farm located in Cordoba province (Southern Spain) was subjected to necropsy. Pathological compatible lesions and molecular analyses confirmed the first SBV infection in Spain. Afterwards, serum samples from 505 extensively reared domestic ruminants from 29 farms were analysed using both blocking ELISA and virus neutralization test against SBV. The overall seroprevalence was 54.4% (CI95%: 50.0-58.7). Antibodies were detected in 70.6%, 46.0% and 34.8% of cattle, sheep and goats, respectively. A generalized estimating equation model indicated that the main risk factors associated with SBV infection were: species (cattle), age (adult), and absence of animal insecticide treatment. Pathological and molecular results confirmed the presence of SBV in Spain few months after it was firstly identified in Germany. The seroprevalence detected indicates a widespread circulation of SBV in nearby domestic ruminant farms one year after this first outbreak was reported in Spain. Further studies are warranted to determine the spatio-temporal trend of SBV in domestic ruminants in this country.

Analysis of the horse V(H) repertoire and comparison with the human IGHV germline genes, and sheep, cattle and pig V(H) sequences.

We have constructed a chimeric antibody single-chain Fv (scFv) fragments phage-displayed library that combines an invariant human V(L) chain with the repertoire of V(H) domains amplified from a horse immunized against scorpion venom. To gain insight into the equine V(H) repertoire, the V(H) sequences of 46 unique clones randomly chosen from the library prior to antigenic selection were analyzed. Comparisons with previously reported equine V(H) sequences, as well as with the repertoire of human IGHV germline genes and known V(H) sequences of sheep, cattle and pig, suggest that the equine IGH locus harbors at least three IGHV gene families. Two families belong to clan II while the other was classified into clan I. The horse sequences were also found to encode a diverse repertoire of canonical structures. The most populated equine IGHV gene family, named IGHV1, and another family termed IGHV3, encode two out of the three canonical structures so far described for CDR1. The IGHV2 gene family has the third canonical structure at CDR1. In CDR2, nine loop lengths were found, with four of them matching the pattern of typical canonical structures. The remaining five CDR2 loop lengths are shorter or longer than those reported for human IGHV germline genes and known sequences of sheep, cattle and pig. The analysis of CDR3 loops indicates a length distribution broader than previous reports for horses; being similar to that of humans, sheep and pigs. Moreover, equine CDR3 loops were found to have a combination of lower content of cysteine and higher proportion of glycine not seen in the other species. This implies less constrained loops and therefore more apt for searching the conformational space of antigen-binding sites. Altogether, these findings reveal a more diverse perspective of the horse V(H) repertoire than previous estimations and lay foundations for future studies of the equine IGH locus.

Monitoring of Schmallenberg virus in Spanish wild artiodactyls, 2006-2015.

Schmallenberg disease is an emerging disease that affects domestic and wild ruminants in Europe. An epidemiological survey was carried out to assess exposure to Schmallenberg virus (SBV) in wild artiodactyls in Spain between 2006 and 2015. A total of 1751 sera from wild artiodactyls, including 1066 red deer, 304 fallow deer, 192 mouflon, 109 wild boar, 49 roe deer and 31 Spanish ibex were tested for antibodies against SBV by ELISA and confirmed by virus neutralization test. SBV was not detected between the 2006/2007 and the 2010/2011 hunting seasons. Overall seroprevalence (including samples collected between the 2011/2012 and 2014/2015 hunting seasons) was 14.6% (160/1099; 95%CI: 12.7-16.6). Mean SBV seroprevalence was 13.3±2.6% in red deer, 23.9±4.2% in fallow deer, 16.4±6.1% in mouflon and 2.8±3.1% in wild boar. No antibodies against SBV were found in roe deer or Spanish ibex. The presence of SBV RNA was confirmed in three of 255 (1.2%) spleen samples from wild ruminants analysed by rRT-PCR. In a multivariate mixed-effects logistic regression model, the main risk factors associated with SBV seroprevalence were: species (fallow deer, red deer and mouflon), age (adults) and interactions between hunting areas of more than 1000 hectares and hunting season (2012/2013, 2013/2014 and 2014/2015). The hypothesis of endemic circulation of SBV in the last few years is supported by the detection of SBV RNA in animals sampled in 2011 and 2015, as well as antibodies detected at low level in juveniles in 2012, 2013 and 2014. The results indicate that SBV circulated in wild ruminant populations in Spain during the same period when the virus was first reported in northern Europe, and at least five months before the first case was officially reported in livestock in Spain.

Origin, distribution, and potential risk factors associated with influenza A virus in swine in two production systems in Guatemala.

BACKGROUND: Guatemala is the country with the largest swine production in Central America; however, evidence of influenza A virus (IAV) in pigs has not been clearly delineated. OBJECTIVES: In this study, we analyzed the presence and spatial distribution of IAV in commercial and backyard swine populations. METHODS: Samples from two nationwide surveys conducted in 2010 and 2011 were tested using virological (rRT-PCR and virus isolation) and serological (ELISA and hemagglutination inhibition) assays to detect IAV. RESULTS: Influenza A virus was detected in 15.7% of the sampled pigs (30.6% of herds) in 2010 and in 11.7% (24.2% of herds) in 2011. The percentage of seropositive pigs was 10.6% (16.1% of herds) and 1.4% (3.1% of herds) for each year, respectively. Three pandemic H1N1 and one seasonal human-like H3N2 viruses were isolated. Antibodies against viruses from different genetic clusters were detected. No reassortant strains with swine viruses were detected. The H3N2 virus was closely related to human viruses that circulated in Central America in 2010, distinct to the most recent human seasonal vaccine lineages. Spatial clusters of rRT-PCR positive herds were detected each year by scan statistics. CONCLUSIONS: Our results demonstrate circulation of IAV throughout Guatemala and identify commercial farms, animal health status, and age as potential risk factors associated with IAV infection and exposure. Detection of human-origin viruses in pigs suggests a role for humans in the molecular epidemiology of IAV in swine in Guatemala and evidences gaps in local animal and human surveillance.

[Biological and immunological characteristics of the poison of Bothrops cotiara (Serpentes: Viperidae)]. / Características biológicas e inmunológicas del veneno de Bothrops cotiara (Serpentes: Viperidae).

Bothrops cotiara is a venomous snake sporadically found in the province of Misiones in Argentina, South of Brazil and Paraguay. Data on the clinics of the envenomation produced by its bite and on its venom are scarce. There is no information on the neutralizing capacity of the antivenoms available. In this study, the lethal potency, hemorrhagic, necrotizing, coagulant and thrombin-like, defibrinogenating, indirect hemolytic and fibrinolytic activities of the venom of B. cotiara specimens from the province of Misiones were determined. The toxic activities were within the range of those described for the other Bothrops species from Argentina, and the electrophoretic and chromatographic studies showed similarities with those described for the other bothropic venoms. The immunochemical reactivity of six South American anti Viper antivenoms (ELISA) have a strong reactivity with all the antivenoms studied. The neutralizing capacity of three of these therapeutic antivenoms against the lethal potency and hemorrhagic, necrotizing, coagulant, thrombin-like and hemolytic activities showed a very close neutralizing capacity. Our data strongly suggest that the antivenoms for therapeutic use available in this area of South America are useful to neutralize the toxic and enzymatic activities of the venom of this uncommon specie of Bothrops.

Seroprevalence and risk factors associated to Mycobacterium bovis in wild artiodactyl species from southern Spain, 2006-2010.

The control of bovine tuberculosis (bTB) is at a critical point in the last stage of eradication in livestock. Wildlife species recently have emerged infected with TB in Europe, particularly ungulates in the Iberian Peninsula. Epidemiological information regarding TB in wild ungulates including affected species, prevalence, associated risk factors and appropriate diagnostic methods need to be obtained in these countries. A cross-sectional study was carried out on wild artiodactyl species, including Eurasian wild boar (Sus scrofa) red deer (Cervus elaphus), roe deer (Capraelus capraelus), fallow deer (Dama dama), Spanish ibex (Capra pyrenaica hispanica) and mouflon (Ovis musimon), in Spain to assess the seroprevalence against Mycobacterium bovis or cross-reacting members of the Mycobcaterium tuberculosis complex (MTBC), and to provide information on associated risk factors. Previously, two in-house indirect enzyme linked immunosorbent assays (bPPD-ELISA and MPB83-ELISA) were developed using known TB status sera. Positive reference sera were selected from infected animals confirmed by culture. The M. bovis isolates belonged to spoligotypes SB0121, SB0120, SB0295, SB0265 and SB0134. Two hundred and two out of 1367 (7.5%; 95% CI: 6.1-8.9) animals presented antibodies against M. bovis by both bPPD-ELISA and MPB83-ELISA. Significantly higher TB seroprevalence was observed in wild boar compared to the other species analyzed. Interestingly, seropositivity against M. bovis was not found in any out of 460 Spanish ibex analyzed. The logistic regression model for wild boar indicated that the seropositivity to M. bovis was associated with age, location and year of sampling, while the only risk factor associated with M. bovis seroprevalence in red deer and fallow deer was the age. The seroprevalence observed indicates a widespread exposure to MTBC in several wild artiodactyl species in southern Spain, which may have important implications not only for conservation but also for animal and public health.

Heterologous expression of a gene that codes for Pg8, a scorpion toxin of Parabuthus granulatus, capable of generating protecting antibodies in mice.

A novel peptide named Pg8 was purified from the venom of the South African scorpion Parabuthus granulatus and its primary structure was determined. It contains 63 amino acid residues tightly folded by 4 disulfide bridges. The gene coding for this peptide was cloned from a cDNA library. By recursive PCR strategy a hybrid gene was constructed having a factor X recognition site for proteolysis and a modified sequence for preferential codon usage of E. coli. A pQE30 molecular vector already contained a His-tag was used for expression. This construction was expressed in BL21 and Origami strains. The fusion protein from inclusion bodies was separated by HPLC (yield approximately 5mg/L) and properly folded in vitro. Lethality tests showed that the recombinant peptide was toxic and was used to immunize mice. A volume of 0.25ml of the anti-serum produced was capable of protecting up to 3 LD(50) doses of pure toxin Pg8 but also, and more importantly, the entire soluble venom.

Características biológicas e inmunológicas del veneno de Bothrops cotiara (Serpentes: Viperidae) / Biological and immunological characteristics of the poison of Bothrops cotiara (Serpentes: Viperidae)

Bothrops cotiara is a venomous snake sporadically found in the province of Misiones in Argentina, South of Brazil and Paraguay. Data on the clinics of the envenomation produced by its bite and on its venom are scarce. There is no information on the neutralizing capacity of the antivenoms available. In this study, the lethal potency, hemorrhagic, necrotizing, coagulant and thrombin-like, defibrinogenating, indirect hemolytic and fibrinolytic activities of the venom of B. cotiara specimens from the province of Misiones were determined. The toxic activities were within the range of those described for the other Bothrops species from Argentina, and the electrophoretic and chromatographic studies showed similarities with those described for the other bothropic venoms. The immunochemical reactivity of six South American anti Viper antivenoms (ELISA) have a strong reactivity with all the antivenoms studied. The neutralizing capacity of three of these therapeutic antivenoms against the lethal potency and hemorrhagic, necrotizing, coagulant, thrombin-like and hemolytic activities showed a very close neutralizing capacity. Our data strongly suggest that the antivenoms for therapeutic use available in this area of South America are useful to neutralize the toxic and enzymatic activities of the venom of this uncommon specie of Bothrops.

Bothrops cotiara es una serpiente que se encuentra en la provincia de Misiones (Argentina), el Sur de Brasil y Paraguay. La información sobre las características clínicas de los accidentes por esta serpiente es muy escasa y existen pocos datos sobre su veneno y la capacidad neutralizante de las actividades tóxicas del mismo por antivenenos terapéuticos. En este trabajo se estudiaron características bioquímicas, actividades tóxicas y la reactividad inmunoquímica del veneno de B. cotiara. Seis antivenenos anti Viperinos Sudamericanos fueron estudiados frente a este veneno por el método ELISA y se probó la capacidad neutralizante de tres de estos frente a las actividades hemorrágica, necrotizante, procoagulante, trombina-símil, hemolítica indirecta y la potencia letal de veneno de ejemplares de B. cotiara de la provincia de Misiones. Los patrones cromatográficos y electroforéticos mostraron características similares a los de otros venenos de Bothrops. Las actividades tóxicas estuvieron dentro de los ámbitos descritos para los venenos botrópicos. Los seis antivenenos mostraron gran reactividad inmunoquímica por ELISA y las potencias neutralizantes de los tres estudiados fueron muy próximas para las actividades letal, hemorrágica, necrotizante, hemolítica indirecta, coagulante y trombina-símil. Los resultados de los estudios de neutralización indicarían que ante la mordedura de esta poco común especie de Bothrops, pueden usarse los diferentes tipos de antivenenos botrópicos o botrópico-crotálicos para uso terapéutico disponibles en esa región.