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Bovine tuberculosis (TB) is a chronic disease caused mainly by Mycobacterium bovis, a zoonotic pathogen that has a worldwide distribution causing serious economic losses for milk and meat producers. In Chile, the disease in dairy cattle has a heterogeneous distribution, where the Metropolitan Region concentrates the highest animal prevalence and the main challenge for the national control and eradication programme. In this epidemiological context, vaccination with the M. bovis Bacillus Calmette-Guerin (BCG) vaccine might be a useful strategy for disease prevention and control. The objective of this study was to assess the efficacy and impacts on productivity and fertility of vaccination with the BCG Russia strain in 11 month-old heifers from a dairy farm, under a natural transmission condition. Sixty-two animals were vaccinated via the subcutaneous route with the equivalent of one human dose of BCG, and 60 control animals received saline. Subsequently, blood sampling was performed at 3, 6, 9, 12, 15 and 18 months post-inoculation, and infection status was determined using the IFNγ release assay (IGRA) with the DIVA (differentiate infected from vaccinated animals) antigens ESAT-6, CFP-10 and Rv3615c. Efficacy was calculated as the percentage of reduction in the incidence of infection attributable to vaccination, which showed a statistically significant level of overall protection of 66.5%. No adverse effects on fertility and production were recorded. In contrast, we observed beneficial effects of vaccination on several milk production parameters, with the milk yield in the first 100 days after calving in the BCG group significantly higher compared to unvaccinated heifers (p

The Darwin's fox (Lycalopex fulvipes) is one of the most endangered carnivores worldwide, with the risk of disease spillover from domestic dogs being a major conservation threat. However, lack of epidemiologic information about generalist, non-dog-transmission-dependent protozoal and bacterial pathogens may be a barrier for disease prevention and management. To determine the exposure of some of these agents in Darwin's fox populations, 54 serum samples were collected from 47 Darwin's foxes in Southern Chile during 2013-18 and assessed for the presence of antibodies against Brucella abortus, Brucella canis, Coxiella burnetii, pathogenic Leptospira (serovars Grippotyphosa, Pomona, Canicola, Hardjo, and Copehageni), Toxoplasma gondii, and Neospora caninum. The highest seroprevalence was detected for T. gondii (78%), followed by pathogenic Leptospira (14%). All the studied Leptospira serovars were confirmed in at least one animal. Two foxes seroconverted to Leptospira and one to T. gondii during the study period. No seroconversions were observed for the other pathogens. No risk factors, either intrinsic (sex, age) or extrinsic (season, year, and degree of landscape anthropization), were associated with the probability of being exposed to T. gondii. Our results indicate that T. gondii exposure is widespread in the Darwin's fox population, including in areas with minimal anthropization, and that T. gondii and pathogenic Leptospira might be neglected threats to the species. Further studies identifying the causes of morbidity and mortality in Darwin's fox are needed to determine if these or other pathogens are having individual or population-wide effects in this species. Sin financiación 1.626 JCR (2021) Q2, 70/145 Veterinary Sciences 0.493 SJR (2021) Q2, 172/434 Ecology No data IDR 2021 UEM

Simple Summary Wild canids play a crucial role in the environment, being an ecological agent of flora dispersal, top predators, and environmental sentinels for zoonotic emerging pathogens, such as Brucella spp. and pathogenic Leptospira. In Chile, three species of non-domestic native canids are present, and due to the growing concern about their interaction with humans and domestic animals, it is of utmost relevance to determine the role of these animals in the epidemiology of brucellosis and leptospirosis. This study aimed to detect the exposure to B. abortus, B. canis, and pathogenic Leptospira by serologic, bacteriologic, and molecular techniques in native foxes from rehabilitation and exhibition centers in Central Chile. Forty-six blood samples were obtained from culpeo and grey foxes, detecting exposure to B. canis and L. Javanica in 10.9% and 7.7%, respectively. Exposure was not registered by culture and qPCR in any of the sampled animals. Our results show for the first time in Chile exposure to B. canis in native foxes, highlighting the need to establish integrated surveillance programs to better evaluate the role of wild animals in the epidemiology of emerging zoonotic pathogens that may affect One Health. Abstract Brucella abortus, B. canis, and pathogenic Leptospira are zoonotic pathogens that infect humans, as well as domestic and wild animals. In wild canids, they may affect their fertility and reproduction, threatening their conservation. Wild canids play a crucial role in the environment as meso- and top-predators and environmental sentinels for zoonotic pathogens. In Chile, three species of wild canids are present, and due to changes in land use and environmental dynamics, it is of utmost relevance to determine the role of these species in the epidemiology of brucellosis and leptospirosis. This study aimed to detect the exposure to B. abortus, B. canis, and pathogenic Leptospira by serologic, bacteriologic, and molecular techniques in native foxes from rehabilitation and exhibition centers in Central Chile. Forty-six blood samples were obtained from Lycalopex culpaeus and L. griseus, detecting 10.9% of seropositivity to B. canis and 7.7% to L. Javanica. No seropositivity was seen for B. abortus. Exposure was not registered by culture and qPCR in any of the sampled animals. Our findings are the first register of exposure to any Brucella species in wild canids in Chile and highlight the need to establish surveillance programs of these emerging pathogens.

We investigated exposure to

We investigated exposure to Brucella canis and Leptospira spp. in sera from 56 canids sampled between 2008 and 2012 in Tierra del Fuego, Chile. No seropositives to B. canis were found. We detected antibodies against Leptospira spp. in Fuegian culpeo fox (Pseudalopex culpaeus lycoides; 20%), chilla foxes (Pseudalopex griseus; 8%), and dogs (Canis lupus familiaris; 3%).

Paratuberculosis is a chronic intestinal disease of animals caused by Mycobacte-rium avium subsp. paratuberculosis (MAP), which has some pathological features similar to Crohn's disease (CD) in humans. The presence of MAP in food for human consumption and in affected tissues of patients with CD has been detected. Therefore, a causal association between this microorganism and the disease in humans, has been postulated. However, several related studies have failed to confirm this hypothesis and the scientific acceptance of MAP as a zoonotic agent remains controversial. This review presents the main findings related to this issue, contrasting evidences for and against an association between MAP and CD. The need to promote national studies focusing on this area is suggested.

Serum samples from 130 individuals representing 42 species of carnivores, ungulates, and primates from a population of captive mammals in Metropolitan Region in Chile were tested for antibodies against nine serovars of Leptospira interrogans using the microscopic agglutination test. Ten percent of the animals were seropositive to one or more serovars. Seroprevalence was significantly higher in ungulates (20.4%) compared to carnivores (3.8%) and primates (3.4%). There were no significant differences in seroprevalence among sex and age ranges. The most frequent serovar detected was Autumnalis, present in 53.4% of antibody-positive animals. Most positive animals had titers of ≤1 : 200, except for a maned wolf ( Chrysocyon brachyurus ) with titers of 1 : 400 against serovar Hardjo. To the authors' knowledge, this is the first report of Leptospira exposure detected in native endangered pudu ( Pudu puda ) and the first confirmation of exposure to L. interrogans in captive wild mammals in Chile. Leptospirosis should be considered as a differential diagnosis in future disease presentation for hepatitis or abortions in captive mammals in Chile.

Infection with Brucella pinnipedialis and Brucella ceti in marine mammals of the northern hemisphere has been extensively reported. In Chile, the National Antarctic Institute (INACH) and the University of Chile have developed a collaborative study establishing the presence of anti- Brucella

An O-polysaccharide (O-chain) and a hot-water extracted polysaccharide (PS), both obtained from Brucella abortus 1119-3, and a B. melitensis 16 M native hapten (NH) were evaluated by indirect enzyme linked immunosorbent assay (ELISA) on three groups of cattle sera. The sera tested were: (a) 75 sera from cows naturally infected with B. abortus ; (b) 130 sera from non-infected and non-vaccinated cattle; and (c) 61 sera from non-infected heifers recently vaccinated with B. abortus Strain 19 (S19). Sensitivity (Se), specificity (Sp) and the capability to discriminate vaccinated cattle (ADV) were determined. Using PS antigen, Se was 100% and the Sp was 97.7%, while the highest Sp was obtained by using the O-chain (99.2% ). For the NH antigen, Se was 94.7% and the Sp was 90.0%. The ADV of the three antigens was approximately 85%. Statistical analysis showed significant differences between O-chain/PS and O-chain/NH antigens. The agreement among antigens determined by kappa coefficient was 0.899 for O-chain/PS, 0.845 for O-chain/NH and 0.795 for PS/NH.

Paratuberculosis is a chronic intestinal disease of animals caused by Mycobacterium avium subsp. paratuberculosis (MAP), which has some pathological features similar to Crohn's disease (CD) in humans. The presence of MAP in food for human consumption and in affected tissues of patients with CD has been detected. Therefore, a causal association between this microorganism and the disease in humans, has been postulated. However, several related studies have failed to confirm this hypothesis and the scientific acceptance of MAP as a zoonotic agent remains controversial. This review presents the main findings related to this issue, contrasting evidences for and against an association between MAP and CD. The need to promote national studies focusing on this area is suggested.

Corynebacterium pseudotuberculosis is a widespread facultative intracellular pathogen that causes caseous lymphadenitis disease in sheep and goats, and generates cutaneous abscesses and granulomas in horses and cattle. Although some genes have been studied for diagnostic and phylogenetic analysis within the genus Corynebacterium, at subspecies level the pathogen has been poorly analyzed. The aim of this study was to characterize C. pseudotuberculosis strains isolated from domestic animals, through the sequencing of a hypervariable rpoB gene segment. As result, there were identified host associated rpoB polymorphisms in strains infecting sheep, goats and horses from Chile. These differences suggest the existence of bacterial genotypes, in which the nucleotide similarity values were ranging from 98.8 to 99.8%. In conclusion, the analysis of polymorphisms in the partial rpoB sequence can be used as a diagnostic tool that differentiates C. pseudotuberculosis strains at subspecies level.

Resumen La tuberculosis constituye uno de los princi-pales problemas de salud publica en el mundo.Varios estudios han comunicado la utilidad de latecnica de fingerprint con las secuencias deinsercion (IS) 6110 e IS 1081 para la identifica-cion y tipificacion de cepas del complejo Mycobacterium tuberculosis . Ambas secuenciasson especificas de las especies bacterianas quepertenecen a este complejo, pero su presencia ynumero de copias varia entre cepas de M. tuber-culosis y M. bovis. El objetivo de nuestro estudiofue investigar la presencia de las secuenciasIS 6110 e IS 1081 en nueve cepas de Mycobac-terium bovis aisladas de los ganglios mediastinicosde bovinos beneficiados en mataderos de Santia-go de Chile. Se detecto la presencia de IS 1081 entodas las cepas, mientras que IS 6110 solo fuedetectada en 7 de ellas. Los resultados de esteestudio sugieren la utilidad potencial de IS 1081 para ser aplicada en la tipificacion de cepas de M.bovis . La secuencia IS 6110 podria constituir unmarcador genetico adicional en las cepas quecontengan este elemento. Se requiere continuarla caracterizacion de estas secuencias de inser-cion con tecnicas de genotipificacion en que seincluya un mayor numero de muestras, de distin-tas especies animales y provenientes de distintaszonas geograficas, a fin de generar informacionepidemiologica util en futuros programas de con-trol de la enfermedad.

To the Editor: Several wildlife-associated zoonotic agents have played a major role in the emergence of diseases in humans (1). However, diseases can also emerge in wildlife as a result of human activities, such as contamination of the marine environment and its fauna by the disposal of nontreated human sewage. Salmonella enterica is among the agents identified as causing infection in various marine birds and mammals, including pinnipeds, from different geographic regions (2–4). The objective of our study was to determine whether S. enterica infection occurs in pinnipeds from the Chilean coast. During August–December 2010, we obtained samples from 13 South American sea lions (Otaria flavescens) that the sanitary authority found malnourished and stranded at the northern Chilean beaches of Antofagasta (23°40′S; 70°24′W) and Los Vilos (31°54′S; 71°30′W) (Table). The pinnipeds showed no clinical signs or symptoms of disease; however, rectal swab samples were obtained during their stay for rehabilitation at the Buin Marino facilities (Santiago, Chile). After the animals recovered, they were released to their original habitat. Table Characteristics of South American sea lions (Otaria flavescens) tested for infection with Salmonella spp., Chilean coast, August–December 2010* The swab samples were placed in Cary-Blair transport medium (COPAN, Murrieta, CA, USA) for shipment to the laboratory (Laboratory of Infectious Diseases, University of Chile, Santiago). To isolate bacteria, we placed the swab samples into 5 mL of buffered peptone water (Difco APT broth; Becton Dickinson, Franklin Lakes, NJ, USA), incubated them for 24 h at 42°C with agitation, and then aliquots of the suspension were transferred into the following media: modified semisolid Rappaport-Vassiliadis basal medium (Oxoid, Sao Paulo, Brazil) with novobiocin (20 µg/mL), selenite cysteine broth base (Oxoid), and xylose lysine desoxycholate agar (Difco XLD; Becton Dickinson). After the aliquots were incubated at 37°C for 24–48 h, we identified suspected colonies by using biochemical tests and invA gene detection by PCR (5). Results showed that 2 of the 13 animals were infected with S. enterica strains, which were serotyped as S. enterica serotype Newport and S. enterica serotype Havana (Table), according to the Kauffmann-White scheme (6). Testing showed that the strains were susceptible to the following antimicrobial drugs: ampicillin, chloramphenicol, tetracycline, amoxicillin/clavulanic acid, trimethoprim/sulfamethoxazole, cefotaxime, nalidixic acid, nitrofurantoin, ciprofloxacin, ceftazidime, and cefoxitin (7). Our results confirm S. enterica infection in pinnipeds from Chile and, more broadly, the South American coast and contrast with previous unsuccessful attempts to detect Salmonella spp. in pinnipeds from Valdivia, 2,200 km to the south (8). This finding suggests geographic variability in the epidemiology of infection; however, this possibility must be confirmed in additional studies with more samples and additional regions. S. enterica is an endemic bacterium in Chile that causes infection in humans and domestic animals. The Chilean sanitary authority includes S. enterica infection among the list of notifiable diseases, but surveillance is not conducted for S. enterica in wildlife. However, consideration should be given to changing this situation, given a report suggesting S. enterica as a priority for active surveillance (9). In addition, S. enterica serotypes Newport and Havana have been detected in Chile’s human population (10), strengthening the necessity for official support for initiatives addressing the need to elucidate the epidemiology of Salmonella in aquatic animals.

Three soluble antigens were compared by radial immunodiffusion (RID) and agar gel immunodiffusion (AGID) tests: a native haptene (NH) from Brucella melitensis 16M, and a polysaccharide (PS) from B. abortus 1119-3, both obtained by non-hydrolytic methods, and the (O-Chain) polysaccharide extracted also from B. abortus 1119-3 but using an hydrolytic method. Three groups of bovine sera were tested: a) Naturally infected (n = 76); b) Non-infected (n = 130) and c) S-19 vaccinated (n = 61); the sensitivity (Se), the specificity (Sp) and the ability to differentiate vaccinated (ADV) were determined in each group a, b and c respectively. The highest Se in the RID test (84.3%) was achieved by NH; while the three antigens gave 100% Sp. The O-Chain showed 100% ADV in this test. In the AGID test PS antigen showed the best Se (86.6%), and all antigens showed 100% of Sp and ADV. Finally, for its production qualities and efficiency the antigens PS and NH represent a promising alternative for complementary diagnosis of brucellosis. Foram comparados três antígenos solúveis: um hapteno nativo (NH) de B. melitensis 16M, um polissacarídeo (PS) obtido de B. abortus 1119-3 e outro polissacarídeo de cadeia O (O-Chain) originado também da última Brucella. Os testes de imunodifusão radial (RID) e imunodifusão em gel de ágar (AGID) foram confrontados com as três classes de soros bovinos: a) infectados naturalmente (n = 76), b) não infectados (n = 130) e c) vacinados com B19 (n = 61) reagindo a testes sorológicos clássicos. Foram determinadas a sensibilidade (Se), a especificidade (Sp) e a capacidade para discriminar vacinados (ADV). A Se mais alta (84,3%) no teste RID foi demonstrada pelo antígeno NH, enquanto os três antígenos tiveram 100% de Sp. O antígeno O-Chain teve 100% de ADV nesse teste. O teste AGID com estes antígenos demonstrou 100% Sp e ADV, enquanto o antígeno PS mostrou uma melhor Se (86,6%). Finalmente, por sua qualidade de produção e eficiência, os antígenos PS e NH representam uma alternativa segura e econômica para o diagnóstico suplementar da brucelose.