Anti-Brucella canis antibodies in dogs naturally infected with Leishmania infantum and associated histological alterations in the genital tract.

In canine visceral leishmaniasis, coinfections can aggravate the disease. Our aim was to investigate Brucella canis in dogs infected with Leishmania infantum. One hundred and six L. infantum-seropositive dogs were submitted to serology for B. canis, PCR for B. canis and L. infantum, and histopathological analysis of the genital tract. Anti-B. canis antibodies were detected in seven dogs whose clinical signs, L. infantum load and histological alterations were similar to those of seronegative animals. The circulation of anti-B. canis antibodies was low but demonstrates the exposure of dogs to this bacterium in a visceral leishmaniasis-endemic area.

Rhodococcus equi pVAPN type causing pneumonia in a dog coinfected with canine morbillivirus (distemper virus) and Toxoplasma gondii.

Canine morbillivirus (previously, canine distemper virus, CDV) is a highly contagious infectious disease-causing agent that produces immunosuppressive infections and multiple clinical signs. Canine toxoplasmosis is an opportunistic disease characterized by enteric, pulmonary, and neuromuscular signs that might be confused with CDV-induced infections. Rhodococcus equi is a Gram-positive intracellular facultative bacterium that is also opportunistic in nature, and causes pyogranulomatous infections in humans and multiple host animals, although canine rhodococcosis is rare or unrecognized. The pathogenicity of R. equi is intimately related to the presence of plasmid-encoded virulence-associated proteins (Vap). Three host-adapted virulence plasmid types of R. equi have been recognized: the circular pVAPA and pVAPB are associated with equine and porcine strains, respectively, and the recently detected linear pVAPN virulence plasmid is related to bovine isolates. Nevertheless, data regarding the detection of host-adapted virulence plasmid types of R. equi isolated from companion animals are scarce. This report describes a case of an uncommon coinfection due to R. equi, T. gondii and CDV, which was diagnosed in a pet dog with respiratory distress. In this case, CDV most likely induced immunosuppression, which facilitated opportunistic infections by R. equi and T. gondii. The analysis of the virulence profile of R. equi revealed the novel pVAPN plasmid type, initially related to bovine strains. This is the second report of the bovine-associated pVAPN type in a pet dog, with an unusual coinfection with T. gondii and CDV. These findings represent a public health concern due to the close contact between pet animals and their owners, particularly because the pVAPN plasmid type was recently detected in people with HIV/AIDS from the same geographical region.

New insights into phylogeography of worldwide Brucella canis isolates by comparative genomics-based approaches: focus on Brazil.

BACKGROUND: Canine brucellosis, due to Brucella canis, is a worldwide zoonosis that remains endemic in South America, including Brazil. Implementation of powerful whole-genome sequencing approaches allowed exploring the Brucella genus considered as monomorphic, with, to date, more than 500 genomes available in public databases. Nevertheless, with under-representation of B. canis genomes -only twenty complete or draft genomes-, lack of knowledge about this species is still considerable. This report describes a comparative genomics-based phylogeographic investigation of 53 B. canis strains, including 28 isolates paired-end sequenced in this work. RESULTS: Obtained results allow identifying a SNP panel species-specific to B. canis of 1086 nucleotides. In addition, high-resolution analyses assess the epidemiological relationship between worldwide isolates. Our findings show worldwide strains are distributed among 2 distinct lineages. One of them seems to be specific to South American strains, including Brazil. B. canis South American strains may be identified by a SNP panel of 15 nucleotides, whereas a 22 SNP panel is sufficient to define contamination origin from Brazil. These results lead to the proposal of a possible spread route for dog brucellosis through South America. Additionally, whole-genome analyses highlight the remarkable genomic stability of B. canis strains over time and the sustainability of the infection in São Paulo over 12 year-period. CONCLUSIONS: Significant increase of B. canis genomes available in public databases provides new insights into B. canis infection in South America, including Brazil, as well as in the world, and also offers new perspectives for the Brucella genus largo sensu.

Clostridium perfringens and C. difficile in parvovirus-positive dogs.

The aim of this study was to investigate Clostridium difficile and Clostridium perfringens in 82 diarrheic dogs positive for canine parvovirus type 2 (CPV). Enterotoxigenic C. perfringens type A was isolated from three (3.6%) dogs. One (1.2%) strain was also positive for NetE- and NetF-encoding genes, which are commonly associated with diarrhea in dogs. Toxigenic C. difficile was isolated from one animal (1.2%), which was also positive for A/B toxins. The present study identified C. difficile and C. perfringens infection in CPV-positive dogs. Further studies are necessary to clarify if clostridial infections may predispose or potentiate CPV-infection in dogs or vice versa.

Dogs and Opossums Positive for Vaccinia Virus during Outbreak Affecting Cattle and Humans, São Paulo State, Brazil.

During a vaccinia virus (VACV) outbreak in São Paulo State, Brazil, blood samples were collected from cows, humans, other domestic animals, and wild mammals. Samples from 3 dogs and 3 opossums were positive for VACV by PCR. Results of gene sequencing yielded major questions regarding other mammalian species acting as reservoirs of VACV.

Serological and Molecular Survey of Brucella Species in Owners and Their Dogs Living on Island and Mainland Seashore Areas of Brazil.

Background: Although Brucella abortus, Brucella suis, and Brucella canis may infect humans and dogs worldwide, no study to date has assessed and compared owners and their dogs between island and mainland seashore areas. Materials and Methods: Accordingly, the study herein has applied serological tests, including Microplate Agglutination Test with 2-Mercaptoethanol, immunochromatographic assay, and Rose Bengal Test, and a Brucella genus-specific PCR assay to 195 owners and their 148 dogs living on 1 mainland seashore area and three nearby oceanic islands of southern Brazil. Results: No seropositivity to B. abortus and B. suis was detected in owner or dog sera. Anti-B. canis seropositivity was observed in 3/148 (2.0%) dogs, but no owner sample was seropositive to B. canis. In addition, all blood samples from both owners and dogs were negative on Brucella genus-specific PCR assay. Conclusions: The seropositive dogs were not related and lived on the seashore mainland area of Guaraqueçaba city. The absence of seropositivity on the islands and the low seropositivity on the seashore mainland could be attributed to geographic isolation, and suggest the low impact of the disease in the region. Despite being a zoonotic disease, brucellosis by B. canis is not included in the National Program for Control and Eradication of Brucellosis, and its diagnosis and notification are not mandatory. The presence of seropositive dogs highlights the risk to human health and the importance of epidemiological surveillance actions in the region, as well as the need for the implantation of preventive measures to avoid the transmission of the pathogen.

One Health approach for Brucella canis: Serological and molecular detection in animal-hoarding individuals and their dogs.

Animal hoarding disorder (AHD) is classified as a psychiatric obsessive-compulsive condition characterized by animal accumulation and often accompanied by unsanitary conditions and animal cruelty. Although AHD may increase pathogen transmission and spread, particularly for zoonotic diseases, human and dog exposure in such cases has yet to be fully established. Accordingly, this study aimed to assess Brucella canis in 19 individuals with AHD (11 households) and their 264 dogs (21 households) in Curitiba, the eighth largest city in Brazil, with approximately 1.8 million habitants. Anti-B. canis antibodies were detected by the 2-mercaptoethanol microplate agglutination test (2ME-MAT) and by a commercial lateral flow immunoassay (LFIA), while molecular detection of previously positive seropositive samples was performed by conventional PCR. Although all the human samples were 2ME-MAT negative, 12/264 (4.5%, 95% Confidence Interval: 2.0-7.0%) dog samples were 2ME-MAT and LFIA positive, with 2ME-MAT titers ranging from 20 to 640. At least one dog in 4/21 (19.0%, 95% CI: 2.0-46.0%) households was seropositive. Despite the absence of seropositivity in individuals with AHD and the comparatively low seroprevalence in dogs, B. canis circulation and outbreaks should be considered in such human populations due to the high burden and recurrent character of B. canis exposure in high-density dog populations and the constant introduction of susceptible animals.

Serological study of vaccinia virus reservoirs in areas with and without official reports of outbreaks in cattle and humans in São Paulo, Brazil.

Vaccinia virus (VACV), the etiological agent of an exanthematic disease, has been associated with several bovine outbreaks in Brazil since the end of the global vaccination campaign against smallpox. It was previously believed that the vaccine virus used for the WHO global campaign had adapted to an unknown wild reservoir and was sporadically re-emerging in outbreaks in cattle and milkers. At present, it is known that Brazilian VACV is phylogenetically different from the vaccinia virus vaccinal strain, but its origin remains unknown. This study assessed the seroprevalence of orthopoxviruses in domestic and wild animals and farmers from 47 farms in three cities in the southwest region of the state of São Paulo with or without official reports of outbreaks in cattle or humans. Our data indicate a low seroprevalence of antibodies in wild animals and raise interesting questions about the real potential of wild rodents and marsupials as VACV reservoirs, suggesting other routes through which VACV can be spread.

Overview of Q fever in Brazil: an underestimated zoonosis.

This review aims to provide current information about Q fever, elucidating the etiological, epidemiological, pathogenic, clinical, diagnostic, therapeutic, and prophylactic aspects of the disease for the medical community. We discuss the main forms of presentation of the agent, its ability to persist in the body, the infinite possibilities of susceptible hosts, the main known forms of transmission, its importance in populations at occupational risk, and the role of arthropods in the natural history of the disease. Focusing on Brazil, we present the cases already described and studies developed since its first report, and how there is still much to unravel. We are aware of the possibilities of the persistence of the agent and the development of severe clinical pictures and the specific treatments currently instituted. We also wish to raise awareness about the future, the new genotypes that are emerging, the need to study the effects of vaccines, and the impact of Q fever on the population. Q fever is a poorly understood disease in Latin America, and recent studies, especially in Brazil, have revealed the importance of developing new studies.

Molecular detection of Leptospira spp. in small wild rodents from rural areas of São Paulo State, Brazil.

BACKGROUND: Leptospirosis represents a One Health issue, affecting humans and animals. This study investigated pathogenic leptospires in small wild rodents in São Paulo, Brazil. METHODS: Kidney samples from 164 rodents underwent qPCR testing, targeting pathogenic Leptospira spp. RESULTS: Thirty-five animals (21.34%) tested positive, including five rodent species: Akodon montensis (2/21; 9.5%), Necromys lasiurus (1/4; 25%), Oligoryzomys nigripes (24/92; 26.1%), Oligoryzomys flavescens (5/26; 19.2%), and Sooretamys angouya (3/14; 21.4%). Botucatu municipality exhibited the highest prevalence, with 42.5% (20/47) of the animals testing positive. CONCLUSIONS: The presence of Leptospira spp. in wild rodents suggests they may be chronic carriers, contaminating the environment.

Comparison of Three Serologic Tests for the Detection of Anti-Coxiella burnetii Antibodies in Patients with Q Fever.

The performance of a commercial immunofluorescence assay (IFA commercial), an in-house immunofluorescence assay (IFA in-house) and an indirect enzyme-linked immunosorbent assay (ELISA) were evaluated in the detection of antibodies anti-C. burnetii in the serum of Q fever patients and persons without the disease. For the study, seropositive and seronegative samples for Q fever (n = 200) from a serum bank of the Instituto Adolfo Lutz in Brazil were used. Commercial IFA was considered in this study as the gold standard for diagnosing Q fever. The in-house IFA demonstrated good agreement with the commercial test, showing high sensitivity (91%) and specificity (97%) compared to the gold standard, with a Kappa coefficient of 0.8954. The indirect ELISA test showed lower agreement with the gold standard, showing low sensitivity (67%), although the specificity of the technique was high (97%) and the Kappa coefficient was moderate (0.6631). In-house IFA is an excellent alternative for diagnosing Q fever.

Bacterial identification in cerebrospinal fluid of domestic species with neurologic signs: a retrospective case-series study in 136 animals (2005-2021).

Central nervous system (CNS) infections comprise life-threatening clinical conditions in domestic species, and are commonly related to severe sequelae, disability, or high fatality rates. A set of bacterial pathogens have been identified in central nervous infections in livestock and companion animals, although the most of descriptions are restricted to case reports and a lack of comprehensive studies involving CNS-related bacterial infections have been focused on a great number of domestic species. In this scenario, we retrospectively investigated selected epidemiological data, clinical findings, bacteriological culture, and in vitro susceptibility patterns of 136 nonrepetitive neurologic cases in domestic species (2005-2021). Bacterial isolates were recovered from 25% (34/136) of the cerebrospinal fluid (CSF) sampled. The isolates were obtained from cattle (9/136 = 6.6%), dogs (7/136 = 5.1%), horses (6/136 = 4.4%), goats (3/136 = 2.2%), pigs (3/136 = 2.2%), sheep (3/136 = 2.2%), cats (2/136 = 1.5%), and asinine (1/136 = 0.7%). Among animals with bacterial isolation, Staphylococcus aureus (6/34 = 17.6%), Escherichia coli (5/34 = 14.7%), Staphylococcus beta-hemolytic (5/34 = 14.7%), and Trueperella pyogenes (3/34 = 8.8%) were predominant, in addition to a miscellaneous of other bacteria isolated in minor frequency, e.g., Corynebacterium pseudotuberculosis, Enterobacter cloacae, Mannheimia haemolytica, Pseudomonas aeruginosa, and Streptococcus equi subsp. equi. In vitro susceptibility tests of isolates revealed that amoxicillin/clavulanic acid (11/13 = 84.6%), cephalexin (9/11 = 81.8%), and florfenicol (9/12 = 75%) were the most effective antimicrobials. Conversely, isolates exhibited resistance mainly to tetracycline (6/10 = 60%), penicillin (6/11 = 54.5%), and trimethoprim/sulfamethoxazole (5/11 = 45.5%). Also, multidrug resistance to ≥ 3 classes of antimicrobials was found in 23.5% (8/34) strains. Data relative to the outcome was available in 79.4% (27/34) of animals that had bacterial isolation, and from these, the lethality rate was 92.6% (25/27). Incoordination (14/34 = 41.2%), recumbency (11/34 = 32.4%), apathy (10/34 = 29.4%), anorexia (9/34 = 26.5%), blindness (7/34 = 20.6%), seizure (6/34 = 17.6%), limb paresis (5/34 = 14.7%), head-pressing (4/34 = 11.8%), and nystagmus (3/34 = 8.8%) were the most frequent clinical signs. A variety of bacterial pathogens were identified in the CSF of domestic species showing neurologic signs, with a predominance of staphylococci, streptococci, and enterobacteria. High lethality of cases, poor in vitro efficacy of conventional antimicrobials, and a high in vitro multidrug resistance pattern of isolates were seen. Our results contribute to etiological characterization, antimicrobial resistance patterns, and clinical-epidemiological findings of bacterial infections in domestic species with neurological signs.

No Evidence of Rabies Exposure in Wild Marmosets (Callithrix jacchus) of Northeast Brazil.

Rabies transmitted by wildlife is the main source of human rabies mortality in Latin America and considered an emerging disease. The common marmoset Callithrix jacchus of Brazil is the only known primate reservoir of rabies worldwide. We tested whether alive free-ranging C. jacchus were exposed to rabies in four northeast states that have previously reported rabies-positive dead C. jacchus (Pernambuco and Bahia) or not (Paraíba and Rio Grande do Norte). Our results show no evidence of rabies antibodies or infection in the sampled C. jacchus, suggesting that apparently healthy marmosets are not widely exposed to rabies over their natural range.

Gene Expression Profile Induced by Two Different Variants of Street Rabies Virus in Mice.

Pathogenicity and pathology of rabies virus (RABV) varies according to the variant, but the mechanisms are not completely known. In this study, gene expression profile in brains of mice experimentally infected with RABV isolated from a human case of dog rabies (V2) or vampire bat-acquired rabies (V3) were analyzed. In total, 138 array probes associated with 120 genes were expressed differentially between mice inoculated with V2 and sham-inoculated control mice at day 10 post-inoculation. A single probe corresponding to an unannotated gene was identified in V3 versus control mice. Gene ontology (GO) analysis revealed that all of the genes upregulated in mice inoculated with V2 RABV were involved in the biological process of immune defense against pathogens. Although both variants are considered pathogenic, inoculation by the same conditions generated different gene expression results, which is likely due to differences in pathogenesis between the dog and bat RABV variants. This study demonstrated the global gene expression in experimental infection due to V3 wild-type RABV, from the vampire bat Desmodus rotundus, an important source of infection for humans, domestic animals and wildlife in Latin America.

Diagnosis failure of bovine leukosis: serology variation during the peripartum period.

This study demonstrates the influence of pregnancy on serum diagnosis of enzootic bovine leukosis (EBL), emphasizing the importance of routine testing to maintain herd health. For this, 143 pregnant cows were sampled in duplicate (30 days before and 15 days after calving). For EBL diagnosis, samples were submitted to agar gel immunodiffusion testing (AGID). Different results were observed before and after delivery in seventy-six serum samples (53.15%), indicating variations in the levels of serum globulins in the blood during the peripartum period. Therefore, using a single sample for serological diagnosis during the birth season might not represent the correct infection status of animal health due to physiological variations in antibody concentrations.

Factors Limiting the Appropriate Use of Rabies Post-exposure Prophylaxis by Health Professionals in Brazil.

Post-exposure prophylaxis (PEP) is necessary to prevent the fatal onset of rabies but requires optimization to avoid overuse in populations at risk of rabies. In Brazil, the incidence of dog bites remains high, with almost half of dog-bite patients not receiving the PEP recommended by the Ministry of Health guidelines between 2008 and 2017. In this study, we aimed to identify the factors that limit the appropriate prescribing of PEP by interviewing health professionals responsible for PEP administration and completion of the 'Information System on Diseases of Compulsory Declaration' (SINAN) form reporting human anti-rabies care for patients seeking health care after a dog bite. We conducted 147 questionnaires (45 questions each) in three Brazilian states (i.e., Rio Grande do Sul, Santa Catarina, Rio Grande do Norte) including questions related to the criteria used by professionals to classify a dog as "suspect" or "rabid", knowledge on PEP prescription guidelines, SINAN and communication with veterinarians. Our analyses showed that most health professionals delivering PEP in these three states struggle to identify a rabies "suspect" dog according to the Ministry of Health guidelines, and to indicate the adequate PEP regimen, with only 11% of professionals prescribing the appropriate PEP under various dog-bite patient scenarios. PEP knowledge score was higher among professionals trained on PEP guidelines and working in facilities with the highest incidence of dog bites. In contrast, PEP knowledge scores did not vary significantly between states, and were not correlated to the professional's level of experience, the number of colleagues available at the health unit or the professional's confidence on prescribing appropriate PEP. Our results suggest that knowledge gaps in PEP administration among health professionals of Brazil can be reduced by implementing training programs to differentiate among rabies risk scenarios, prescribe the corresponding appropriate PEP and improve communication between health and veterinary authorities.

Seropositivity for Coxiella burnetii in suspected patients with dengue in São Paulo state, Brazil.

Q fever and brucellosis are zoonoses that cause fever and other systemic clinical signs in humans; their occurrences are neglected and the differential diagnosis for some diseases is disregarded. This study aimed to investigate the seropositivity for Coxiella burnetii and Brucella spp. antibodies in patients suspected of dengue from 38 municipalities in the state of São Paulo, Brazil. The samples (n = 604) were obtained by convenience from the Adolfo Lutz Institute serum bank. Sera were subjected to an indirect immunofluorescence assay (IFA) using in-house and commercial diagnostic protocols to evaluate C. burnetii positivity. For Brucella spp., sera were subjected to rapid plate serum agglutination with buffered acidified antigen (AAT), slow tube serum agglutination (SAL), and 2-mercaptoethanol (2-ME) techniques. Associations and statistical inferences of the results were performed by logistic regression according to the clinical and demographic variables collected from the patients. Statistical analyses were performed using Statistical Analysis Software (SAS) and associations were considered when p value was <0.05. In all, 129 patients showed positive results for Q fever, indicating a seropositivity of 21.4% (95% CI 18.15-24.85). Patients with 14-20 days of symptoms had 2.12 (95% CI 1.34-3.35) times more chances of being seropositive for Q fever than patients with 7-13 days, and patients with 21-27 days of fever had 2.62 (95% CI 1.27-5.41) times more chances of being seropositive for Q fever than patients with 7-13 days. For the other variables analyzed, there were no significant associations between the groups. No positivity for brucellosis was observed. This is the most comprehensive study of people seropositive for Q fever in São Paulo state and provides additional data for the medical community in Brazil. It is suggested that Q fever may be an important differential diagnosis of febrile illnesses in the region, demanding the government's attention and investment in health.

Phenotypic and molecular identification of Brucella suis biotype 1 in a pig from Brazil-case report.

Brucellosis is a zoonotic disease with a global impact. Brucella suis is one of the most pathogenic species to humans, requiring different measures for the control and/or eradication of the disease. The serological investigation for brucellosis was performed in pigs, horses, dogs, and cattle on a farm with a history of abortion in sows and necropsy of a boar with severe necrosuppurative orchitis. One sow, two cows, and two dogs reveled positive to Rose Bengal Test (RBT), although only the sow had a confirmatory outcome in 2-mercaptoethanol (2-ME). The 2-ME-positive sow was euthanized and microbiological culture of lymph nodes and liver followed by biochemical characterization allowed phenotypic characterization of Brucella suis biotype 1. PCR multiplex Bruce-ladder and Suis-ladder enabled molecular confirmation, respectively, of Brucella suis and biotype 1. The transmission aspects of B. suis to pigs and other domestic species, the combination of diagnostic procedures to diagnosis, as well as human health concerns of brucellosis are discussed.

Molecular detection of Coxiella burnetii in aborted bovine fetuses in Brazil.

In the past decade, cases of Q fever have been reported in Brazil. Although the previous report of Coxiella burnetii in humans and animals, the knowledge about the occurrence of this pathogen in livestock in Brazil is scarce. This study aimed to search C. burnetii and possible coinfections in tissues of aborted bovine fetuses from Brazil. Tissue samples from seventy-six aborted bovine fetuses sent to the laboratory of molecular diagnosis of infectious diseases from 2013 to 2019 were evaluated by real-time PCR for C. burnetii. Overall, 9.2% (7/76) of the samples were positive for C. burnetii. Moreover, the molecular diagnostic history of our lab revealed the coinfection with Neospora spp. in three fetuses and the presence of histopathological features suggestive with fetal neosporosis in another one. The previous report of C. burnetii in humans and animals in the country, with the detection of C. burnetii from tissues of aborted bovine fetuses reported here, reinforces the neglected state of the disease in Brazil and raises the question of the role of the pathogen in reproductive disorders in national livestock.

Spatio-temporal dynamics of rabies and habitat suitability of the common marmoset Callithrix jacchus in Brazil.

Rabies transmitted by wildlife is now the main source of human rabies in the Americas. The common marmoset, Callithrix jacchus, is considered a reservoir of rabies causing sporadic and unpredictable human deaths in Brazil, but the extent of the spillover risk to humans remains unknown. In this study, we described the spatiotemporal dynamics of rabies affecting C. jacchus reported to Brazil's Ministry of Health passive surveillance system between 2008 and 2020, and combined ecological niche modelling with C. jacchus occurrence data to predict its suitable habitat. Our results show that 67 outbreaks (91 cases) of rabies affecting C. jacchus were reported by 41 municipalities between January 2008 and October 2020, with a mean of 5 outbreaks/year [range: 1-14]. The maximum number of outbreaks and municipalities reporting cases occurred in 2018, coinciding with higher surveillance of primate deaths due to Yellow Fever. A mean of 3 [1-9] new municipalities reported outbreaks yearly, suggesting potential spatial expansions of the C. jacchus variant in northeastern Brazil and emerging rabies spillover from vampire bat Desmodus rotundus to C. jacchus in the north and south. Outbreaks were concentrated in the states of Ceará (72%) and Pernambuco (16%) up to 2012, but are now reported in Piauí since 2013, in Bahia since 2017 (D. rotundus' antigenic variant, AgV3) and in Rio de Janeiro since 2019 (AgV3). Besides confirming suitable habitat for this primate in the northeast and the east coast of Brazil, our Maximum Entropy model also predicted suitable habitat on the north and the west states of the country but predicted low habitat suitability among inland municipalities of the Caatinga biome reporting rabies. Our findings revealed new areas reporting rabies infecting C. jacchus, highlighting the need to implement strategies limiting spillover to humans and to better understand the drivers of C. jacchus rabies dynamics.