Equine genital leptospirosis: Evidence of an important silent chronic reproductive syndrome.

Leptospirosis may be associated with important syndromes in equines, including reproductive ones. Recently, our group demonstrated a reproductive syndrome of leptospirosis in ruminants (Bovine Genital Leptospirosis - BGL), that presents its own agent, particular diagnostic methods, and specific treatment and prevention, requiring special attention. We realized that the genital syndrome of leptospirosis may not be exclusive to ruminants and may also affect horses. The aim of the present study is to gather the available data on leptospirosis in equine reproduction and propose a new genital leptospirosis syndrome in horses, which we have named Equine Genital Leptospirosis (EGL). The main agent is most probably serovar Bratislava (serogroup Australis), whose role has been increasingly recognized in the etiology of infection, presenting a worldwide distribution. The most probable relevant transmission route in the EGL context is the sexual transmission. Subfertility, estrus repetition, and, less commonly, late-term abortions are the most common effects. Serology may not be adequate to diagnose this chronic silent reproductive leptospiral infection. As most studies regarding equine leptospirosis investigate urinary samples, EGL is vastly underdiagnosed, and the disease is little studied and underestimated. Therefore, PCR, particularly from cervicovaginal mucus (CVM) and uterine fragments, turns out to be a rapid and definitive diagnosis choice. In order to mitigate the effects of the disease in equines, triad antibiotic therapy, vaccination, and environmental management are essential. Adequate recognition of the particularities of this syndrome may help to highlight its occurrence and contribute to a broader understanding of its clinical manifestations, use of a correct diagnosis, and development of novel approaches for its control.

Equine leptospirosis: Experimental challenge of Leptospira interrogans serovar Bratislava fails to establish infection in naïve horses.

BACKGROUND: Little information is available about experimental inoculation of leptospirosis in horses and the pathogenicity of Leptospira interrogans serovar Bratislava in this host. OBJECTIVES: To determine the serological, clinical, pathological and haematological responses of horses to L. interrogans serovar Bratislava strain PigK151. STUDY DESIGN: Randomised controlled in vivo experiment. METHODS: Ten seronegative female foals were divided into 2 groups, control (n = 4) and challenged (n = 6). The challenged group received 1 × 109 leptospires divided equally between topical ocular and intraperitoneal injections. Blood and urine samples were analysed. The temperature was recorded daily for the first 9 days, then weekly. Sera were tested by microscopic agglutination test (MAT). Automated complete blood count, differential and chemistry panel were performed. Histopathological analysis was performed on sections of liver, kidney, urinary bladder, uterine body and pineal gland. Sample culturing was performed from blood, urine, liver, kidney, reproductive tract and vitreous humour. RESULTS: No pyrexia was noted. PCR and culture were negative from all samples. Differences between groups were found in CBC, differential counts and serum biochemistry panel (or profile), suggesting that leptospiral challenge triggered an inflammatory response. No evidence of leptospirosis was found from histopathological analysis. All challenged foals developed a humoral response. The MAT allowed the confirmation of the infecting serovar at a later stage, but it also revealed cross-reactive results that were further explained by genomic analysis. MAIN LIMITATIONS: This experimental challenge had two main limitations: (a) the results might have varied if another strain from the same serovar had been used and (b) the use of another route of infection and a higher bacterial dose might have achieved colonisation. CONCLUSIONS: Based on these findings, it may suggest that L. interrogans serovar Bratislava is neither pathogenic nor host-adapted serovar for horses, although these results might have varied if another strain from the same serovar had been used instead.

Relationship between Poaceae pollen and Phl p 5 allergen concentrations and the impact of weather variables and air pollutants on their levels in the atmosphere.

The sensitization to grass pollen is a known problem in European countries. Phl p 5 is an important allergen recognized by the majority of grass sensitized individuals. In this study, we evaluated daily variation in airborne Poaceae pollen and Phl p 5 allergen concentrations to determine whether airborne pollen concentrations alone are sufficient to reflect the actual allergenic potential of the air. The relationships between the mentioned pollen and allergen concentrations and associated environmental variables were also examined. The airborne particles were collected during the Poaceae flowering season in Bratislava in 2019. Pollen sampling was performed using a Hirst-type sampler, while a cyclone sampler was used for the aeroallergen capturing. Allergenic molecules were quantified by ELISA assay. The associations between pollen and allergen concentrations showed that these two variables are positively correlated; however, the correlation was not significant. We observed the concurrent occurrence of airborne pollen and allergen peaks on the same day. Nevertheless, during some days of the pollen season, the allergen concentrations did not correspond to the airborne pollen values. Moreover, the days with low pollen concentration but high pollen potency and vice versa were observed. The effect of selected environmental variables on daily pollen and allergen concentrations was evaluated through Spearman's correlation analysis. Of all meteorological variables considered, air temperature, precipitation, and relative air humidity were significantly correlated with airborne pollen and/or allergen concentrations. The association with air temperature was positive, while the negative association was observed with precipitation and relative air humidity. Among the atmospheric pollutants, O3 and PM10 were significantly and positively associated with both pollen and allergen concentrations, whereas CO and PM2.5 were significantly and positively associated only with pollen concentration.

Leptospirosis in an asplenic patient -case report.

BACKGROUND: The presentation of clinical leptospirosis has been historically associated with animal workers, slaughterhouse workers and medical veterinarians. This association has shifted to be related to flooding events and outdoor activities; few cases are related to high-risk factors found in immunosuppressed patients. Scarcely a handful of cases have serological evidence of immune response against Leptospira serovar Bratislava representing serogroup Australis, a serovar associated with poor reproductive performance in swine and horses, and recently with cats. CASE PRESENTATION: Herein, we describe a rare clinical presentation of disseminated Leptospira infection in an immunosuppressed 65-year-old woman. She was admitted to the emergency room with fever, bacteraemia, bilateral uveitis and pulmonary involvement. The patient denied outdoor activities; she only had wide exposure to faeces and urine from cats living in her home. Her medical history included idiopathic thrombocytopenic purpura (ITP) diagnosed at the age of 18. She did not respond to medical treatment, and a splenectomy was performed. At age 60, she was diagnosed with Chronic Myeloid Leukemia (CML), and was treated with a tyrosine kinase inhibitor (TKI) -Imatinib. The patient voluntarily discontinued the treatment for the last 6 months. After extensive workup, no microorganisms were identified by the commonly used stains in microbiology. The diagnosis was performed through dark-field microscopy, microagglutination test (MAT), Leptospira genus-specific PCR, the IS1500 PCR for identification of pathogenic species, and 16S based sequencing for the genus identification. CONCLUSION: Immunosuppressed patients may acquire uncommon infections from ubiquitous microorganisms. In this case, serology evidence of exposure to Leptospira serovar Bratislava by MAT and the presence of the Leptospira genus were identified. It should be on mind for the diagnosis in otherwise healthy patients, and thoroughly search on splenectomised patients exposed to animals. Additionally, this report highlights the usefulness of PCR for diagnosis of this potentially life-threatening illness.

Passive surveillance of Leptospira infection in swine in Germany.

BACKGROUND: As no current data are available on the prevalence of leptospiral infection in swine in Germany, we analysed laboratory data from diagnostic examinations carried out on samples from swine all over Germany from January 2011 to September 2016. A total of 29,829 swine sera were tested by microscopic agglutination test (MAT) for antibodies against strains of eleven Leptospira serovars. RESULTS: Overall, 20.2% (6025) of the total sample collection tested positive for leptospiral infection. Seropositivity ranged between 16.3% (964) in 2011 and 30.9% (941) in 2016 (January to September only). Of all samples, 11.6% (57.3% of the positives) reacted with only one Leptospira serovar, and only 8.6% (42.7% of the positives) reacted simultaneously with two or more serovars. The most frequently detected serovar was Bratislava, which was found in 11.6% (3448) of all samples, followed by the serovars Australis in 7.3% (2185), Icterohaemorrhagiae in 4.0% (1191), Copenhageni in 4.0% (1182), Autumnalis in 3.7% (1054), Canicola in 2.0% (585), and Pomona in 1.2% (368). Modelling shows that both the year and the reason for testing at the laboratory had statistically strong effects on the test results; however, no interactions were determined between those factors. The results support the suggestion that the seropositivities found may be considered to indicate the state of leptospiral infections in the German swine population. CONCLUSION: Although data from passive surveillance are prone to selection bias, stratified analysis by initial reason for examination and analyses by model approaches may correct for biases. A prevalence of about 20% for a leptospiral infection is most probable for sows with reproductive problems in Germany, with an increasing trend. Swine in Germany are probably a reservoir host for serovar Bratislava, but in contrast to other studies not for Pomona and Tarassovi.

Leptospira interrogans serovars Bratislava and Muenchen animal infections: Implications for epidemiology and control.

Strains of Leptospira interrogans belonging to two very closely related serovars - Bratislava and Muenchen - have been associated with disease in domestic animals, in particular pigs, but also in horses and dogs. Similar strains have also been recovered from various wildlife species. Their epidemiology is poorly understood. Two hundred and forty seven such isolates, from UK domestic animal and wildlife species, were examined by restriction endonuclease analysis in an attempt to elucidate their epidemiology. A representative sub-sample of 65 of these isolates was further examined by multiple-locus variable-number tandem repeat analysis and 22 by secY sequencing. Ten restriction pattern types were identified. The majority of isolates fell into one of three restriction endonuclease analysis pattern types designated B2a, B2b and M2a. B2a was ubiquitous and was isolated from 10 species and represented the majority of the horse and all dog isolates. B2b was very different, being isolated only from pigs, indicating that this type was maintained by pigs. The pattern M2a was reported for the majority of isolates from pigs but also was common in small rodents isolates. Five restriction pattern types were found only in wildlife suggesting that they are unlikely to pose a disease threat to domestic animals. Multiple-locus variable-number tandem repeat analysis identified six clusters. The REA types B2a and B2b were all found in one MLVA cluster while the majority of the M2a strains examined occurred in another cluster. The secY sequencing detected only one sequence type, clustered with other serovars of Leptospira interrogans.

Circulating serovars of Leptospira in cart horses of central and southern Ethiopia and associated risk factors.

Little work has been done on diseases of horses in Ethiopia or tropical regions of the world. Yet, Ethiopia has the largest horse population in Africa and their horses play a pivotal role in their economy as traction animals. A serological and questionnaire survey was therefore conducted to determine the circulating serovars of Leptospira and their association with potential risk factors in the cart horse population of Central and Southern Ethiopia. A total of 184 out of 418 cart horses from 13 districts had antibody titres of 1:100 or greater to at least one of 16 serovars of Leptospira species in Central and Southern Ethiopian horses. A significantly higher seropositivity (62.1%) was noted in horses from the highland agroecology followed by midland (44.4%) and lowland (39.8%). Serovar Bratislava (34.5%) was the predominant serovar followed by serovars Djasiman (9.8%), Topaz (5.98%) and Pomona (5.3%). Age and location proved to be associated with seropositive horses with older horses being more commonly affected and the districts of Ziway (Batu) (Apparent Prevalence (AP)=65.5%), Shashemene (AP=48.3%) and Sebeta (AP=41.4%) having the highest prevalence. Multivariable logistic regression found risk factors significantly associated with Leptospira seropositive horses were drinking river water (OR=2.8) and horses 7-12 years old (OR=5) and risk factors specifically associated with serovar Bratislava seropositive horses were drinking river water (OR=2.5), horses ≥13 years (OR=3.5) and the presence of dogs in adjacent neighbouring properties (OR=0.3). Dogs had a protective effect against seropositivity to serovars Bratislava and Djasiman, which may be due to their ability to control rodents. The high seroprevalence confirm that leptospirosis is endemic among horses of Central and Southern Ethiopia. The predominance of serovar Bratislava supports the idea that serovar Bratislava may be adapted to and maintained by the horse population of Central and Southern Ethiopia. This study emphasizes the need for further countrywide serological surveys and isolation of circulating leptospires in animals and humans in order to understand the role of horses in the epidemiology of this disease.

SEROLOGIC SURVEY AND RESULTS OF URINARY PCR TESTING FOR LEPTOSPIROSIS IN CAPTIVE BLACK-TAILED PRAIRIE DOGS (CYNOMYS LUDOVICIANUS).

Leptospirosis is an important zoonotic disease occurring clinically and subclinically in humans and a wide variety of mammal species worldwide. Often, rodents and wild animals are identified as important reservoirs for the disease. Twenty-two captive black-tailed prairie dogs (Cynomys ludovicianus) housed within a zoo were examined as part of a routine census and preventive medicine program. During examinations, blood and urine were collected to screen for exposure to, or infection with, leptospirosis. All animals were apparently healthy at the time of examination. Leptospira microscopic agglutination test identified 12 of 22 (54.5%) prairie dogs with antibody titers ≥1 : 100 against Leptospira interrogans serovar bratislava on initial serologic examination. All prairie dogs within this collection were serologically negative for L. interrogans serovars canicola, hardjo, icterohaemorrhagiae, and pomona and Leptospira kirschneri serovar grippotyphosa. Leptospira polymerase chain reaction (PCR) testing of urine was negative in all animals tested. This report describes evidence that captive prairie dogs may be exposed to leptospirosis, most likely from wild rodent reservoirs; however, serum titers are low, and lack of leptospiral DNA detected by PCR indicates that these captive animals are unlikely to be important reservoirs for the disease.

Molecular studies on European equine isolates of Leptospira interrogans serovars Bratislava and Muenchen.

Strains of Leptospira interrogans belonging to two very closely related serovars ­ Bratislava and Muenchen ­ are known to cause widespread infection of the horse population in many parts of the world. Conventional serological typing of isolates has been unable to differentiate between wildlife, pig, dog and possibly horse maintained isolates and therefore has been unable to provide further insight into their diversity and the relationship between them. Twenty-one such European isolates of serovar Bratislava and Muenchen were examined by restriction endonuclease analysis and multiple-locus variable-number tandem repeat analysis in an attempt to elucidate their epidemiology. The restriction pattern types were identified and fell into one of four REA designed pattern types, B1, B2a, M1, M2a. Nine strains from Northern Ireland and two from Germany belonged to B2a, which is a ubiquitous strain being originally isolated from a large number of wild and domestic animal species in the UK. Five strains were identified as B1 and they came from Portugal, The Netherlands, Germany and Northern Ireland; three strains isolated in Germany belong to M1; two strains belonged to M2a. Genotypes B1 and M1 have, with the exception of one hedgehog isolate, been recovered only from horses and it may indicate their adaptation to this species.

Seropositivity to Leptospira interrogans serovar Bratislava associated to reproductive problems without significant biochemical or hematological alterations in horses / Soropositividade para Leptospira interrogans serovar Bratislava associada a falhas reprodutivas sem alterações hematológicas e bioquímicas significativas em cavalos

The objective was to study haematological and biochemical alterations associated to seropositivity to Leptospira interrogans serovar Bratislava infection in horses with reproductive alterations, such as neonatal deaths, embryonic deaths and abortions. A flock of mares with poor reproductive performance was studied. Eighty-two (58.6 percent) were seropositive (titre 200); 72 of those (87.8 percent) for Bratislava. Slight haematological and biochemical alterations were observed, being more frequent (P<0.05) in horses seropositive versus seronegative. In conclusion horses seropositive for Bratislava had no consistent, severe alteration in values for hematology and biochemistry serum. Those findings reinforce this serovar as adapted to the horse and causing only mild symptoms, focused on reproductive problems.

O objetivo deste trabalho foi estudar alterações hematológicas e bioquímicas associadas à soropositividade para Leptospira interrogans sorovar Bratislava em cavalos com alterações reprodutivas, tais como mortes neonatais, absorção embrionária e abortamentos. Um rebanho de éguas com baixos índices reprodutivos foi estudado. Oitenta e duas (58,6 por cento) foram soropositivas (títulos 200), sendo 72 destas (87,8 por cento) para Bratislava. Foram observadas poucas alterações hematológicas e bioquímicas, mais frequentes (P<0,05) em éguas soropositivas do que soronegativas. Cavalos soropositivos para Bratislava não tinham alterações graves nos valores hematológicos e bioquímicos. Esses achados reforçam que esse sorovar seja adaptado de cavalos e cause apenas sintomas brandos, associados a falhas reprodutivas.

Aplicação de um programa integrado de controle da leptospiroseem eqüinos no Rio de Janeiro, Brasil / Application of an integrated program of leptospirosis control in horsesfrom Rio de Janeiro, Brazil

Um plantel localizado na região serrana do Rio de Janeiro com 140 éguas e oito garanhões foi estudado em março de 2006.Realizou-se sorodiagnóstico para leptospirose de todos os animais do plantel e 82 (55,4%) foram soropositivos.O serovar.Bratislava foi o mais freqüente e identificado em 72 (87,8%) amostras reativas. Diante dos achados, um amplo programa decontrole da infecção foi elaborado, incluindo abordagens vacinais, medicamentosas e epidemiológicas. Doze meses após aimplementação do programa de controle (maio de 2007) constatou-se redução no índice de abortamento de 12% para 4%,morte embrionária de 10% para 2% e morte neonatal de 8% para 1%, totalizando 7% de prejuízos reprodutivos, perante 30%observados antes da implementação do programa de controle. Nesta ocasião, selecionaram-se randomicamente 31 fêmeaspara testagem sorológica. Onze animais (35,48%) apresentaram sororreatividade, a maioria com baixos títulos. Em relação àdistribuição do serovar infectante, sv. Bratislava foi ainda o mais freqüente. Desta forma, conclui-se que a ampla abordagem,incluindo simultaneamente a vacinação, antibioticoterapia e a administração de alguns aspectos ambientais foi imprescindívelpara o sucesso no controle da enfermidade neste rebanho.

A flock from Rio de Janeiro with 140 mares and eight stallions was studied in March, 2006. Serodiagnosis for leptospirosis wasperformed in all the animals and 82 (55.4%) were seroreactive. The serovar Bratislava was the most frequent, in 72 (87.8%) ofthe reactive samples. Considering those findings a broad control program of the disease was applied, including vaccines,antibiotics and epidemiological measures. Twelve months after the beginning of the program (May, 2007) abortion reduced from12% to 4%, embryonic death from 10% to 2% and neonatal death from 8% to 1%, with total reproductive losses decreasing from30% to 7%. In this moment, 31 mares were randomly tested and eleven (35.48%) were seroreactive, most of them with low titres.Bratislava was still the most frequent serovar. Therefore, we conclude that the broad approach of the control program, whichincluded vaccines, antibiotics and correction of some environmental aspects was mandatory for the efficacy of the diseasecontrol.