Serovars Canicola Research Articles

Evaluation of protective efficacy, serological responses, and cytokine modulation induced by polyvalent Leptospira vaccines in hamsters

Whole-cell inactivated vaccines (bacterins) are the only licensed vaccines available for leptospirosis prevention and control, especially in domestic and farm animals. However, despite their widespread use, inconsistencies in their efficacy have been reported. Because immunity induced by bacterins is mainly mediated by antibodies against leptospiral lipopolysaccharides, the involvement of cellular responses is not well-known. The aim of this study was to investigate the efficacy and characterize the humoral and cellular immune responses induced by whole-cell inactivated leptospirosis bacterin formulations containing serovars Bratislava, Canicola, Copenhageni, Grippotyphosa, Hardjoprajitno, and Pomona. For the potency test, hamsters were immunized with one dose of polyvalent bacterins (either commercial or experimental) and then challenged with a virulent Pomona strain. Serological (MAT and IgM and IgG-ELISA) and cellular (cytokine transcription in blood evaluated by RT-qPCR) analyses were performed. The results revealed that vaccination with either bacterin formulation was able to protect 90–100% of the hamsters infected with the Pomona serovar, although most of the surviving animals remained as renal carriers. Specific agglutinating antibodies and significant levels of IgM, IgG, and IgG2 (P < 0.05) that were able to react with the six serovars present in the vaccine formulations were produced, indicating that the vaccines can potentially provide immunity against all strains. The protective immunity of these vaccines was mainly mediated by balanced a Th1/Th2 response, characterized by increased IFN-γ, IL-10 and IL-α transcription. These data support the importance of characterizing immunological responses involved in bacterin efficacy and investing in the improvement of these vaccine formulations.

Serological survey of leptospirosis in horses with historical displacement through different geographic regions in Brazil

Leptospirosis has worldwide occurrence and shows higher incidence in tropical areas. Equines can present several serovars according to geographic region and it is important analyze de possible contribution of animal displacement on the Leptospira spp. strains occurrence. This research aimed to conduct a serological investigation in an equine regiment belonging to the Brazilian Army Guard Cavalry, resident in an urban area of Rio de Janeiro municipality, but with history of displacement between different regions in Brazil. A microscopic agglutination test was performed in a serum bank of 197 horses using 29 Leptospira spp. strains. The test showed 94.92% positivity, with 90.36% of the animals presenting a positive result for two or more serovars. Higher titers (?1:400) could be detected in 54.31% of horses for at least one serovar, whereas seropositivity for more than one bacterial type occurred mostly at lower titers (&lt;1:400). All animals were clinically healthy. Occurrence of serogroup Icterohaemorraghiae in urban areas was confirmed; however, equine serovars Bratislava and Australis presented low frequencies. The serovars Hardjo, Wolffi, and Canicola were detected, and indicated the presence of ruminants and dogs as reservoirs in proximity in some of the places frequented by the animals. It is suggested that travel history has contributed to the high frequency found and a possible greater contact with different types of Leptospira spp. Therefore, veterinarians should consider the history of geographic displacement and other animal species coexistence with horses when conducting their clinical investigation.

Prevalência e fatores associados ao risco da presença de aglutininas anti-Leptospira spp em bovinos de agricultores familiares da bacia leiteira do município de Ji-Paraná - RO, Brasil

ABSTRACT Leptospirosis affects several animal species, including man. This study aimed to evaluate the prevalence of Leptospira spp. and to identify factors associated with the risk of Leptospira spp. in dairy cattle in the municipality of Ji-Paraná, RO, Brazil, sampled by rural sector, from September 2012 to November 2013. Blood samples from 627 dairy cows were randomly collected from 63 farms belonging to six rural sectors. Leptospirosis was diagnosed by the microscopic serum agglutination technique. Of the 627 animals tested, 255 had anti-Leptospira antibodies (40.48%, 95% CI: 36.64-44.31) and 57 of the 63 studied dairy farms (90.5%, 95% CI: 83.23-97.72) had at least one reactive animal. The results indicate that serovar Hardjo had the highest (12.38%. 95% CI: 10.03-15.18) followed by serovars Shermani, Wolffi, Hebdomadis and Canicola occurrence in dairy cows. Additionally, infection was also associated with abortion occurrences in cows of 36 farms (57.14%) and the presence of dogs roaming free with access to pasture, water and cattle in 47 farms (74.60%). Therefore, free-roaming animals are considered a predisposing factor, highlighting the need for adopting prophylactic measures while raising the awareness from rural producers about the importance and the economic losses that leptospirosis may cause.

Seroprevalence of Leptospira Among Selected Mammals on a Wildlife Management Area in Louisiana, USA

From August to December 2018, we collected blood samples from 98 individuals of 11 mammal species to examine seroprevalence of leptospirosis at the Sherburne Wildlife Management Area in central Louisiana, US. Overall, 21.4% of individuals tested positive for antibodies of at least one Leptospira interrogans serovar and six individuals were reactive for two or more serovars. The most prevalent serovar we detected was serovar Bratislava (19.4%), followed by serovar Grippotyphosa (6.1%), serovar Icterohaemorrhagiae and serovar Pomona (2.0%), and serovar Canicola and serovar Hardjo (1.0%). We detected the highest prevalence in fox squirrels (Sciurus niger), hispid cotton rats (Sigmodon hispidus), and feral swine (Sus scrofa), with serovar Bratislava being the most reactive for these three species. Positive samples returned titer results of 100-400 for all species and serovars, with the exception of one feral swine that returned a titer of 1,600 to serovar Bratislava, indicating an active infection. Although the potential effects of leptospirosis on our study species remains unclear, our data contribute information necessary to understand and manage potential risks of Leptospira exposure to wildlife, domestic animals, and humans.

SEROSURVEY FOR SELECTED PARASITIC AND BACTERIAL PATHOGENS IN DARWIN'S FOX (LYCALOPEX FULVIPES): NOT ONLY DOG DISEASES ARE A THREAT.

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.

A serological survey of canine leptospirosis in the city of Belgrade, Serbia

Canine leptospirosis is a zoonosis caused by bacteria belonging to the genus Leptospira. Dogs are one of the animal species involved in the cycle of preservation and transmission of leptospirosis in urban areas. Serological testing for the presence of specific antibodies against Leptospira spp. in dogs was continuously performed between 2010 and 2020 in the city of Belgrade. At the request of the owners themselves, other veterinary laboratories or laboratory clinics, 179 blood sera from 179 dogs were examined in the Laboratory for Immunology, Scientific Institute of Veterinary Medicine of Serbia. Blood sera samples from dogs were examined using the standard microscopic agglutination test (MAT) for the presence of specific antibodies against seven different serovars of Leptospira: Pomona, Icterohaemorrhagiae, Grippotyphosa, Sejroe, Canicola, Bataviae, and Australis. The number of seropositive dogs was 17/179 (9.5%). Among all examined sera, the highest titre of seropositive samples was to serovar Icterohaemorrhagiae (10/17, 58.8%), followed by Pomona (4/17, 23.5%), and serovar Canicola (3/17, 17.6%). Specific antibodies for serovars Grippotyphosa, Sejroe, Bataviae and Australis were not detected in any of the dog sera. Cross-reaction (the presence of two or three titres with different values where one of them was higher than others) between different serovars was diagnosed in a low number of sera (n=4), with the following serovars: Icterohaemorrhagiae and Pomona (n=3) and Pomona and Canicola (n=1). The confirmed specific antibody titres for Leptospira spp. were between 1:100 to 1:3000 (5 sera had titres of 1:100, 7 had titres of 1:300, 4 had titres of 1:1000, and 1 serum had a titre 1:3000). Monitoring canine leptospirosis is a useful tool in preventing leptospirosis in Belgrade.

Seroprevalence of Leptospira spp. in draft horses from indigenous communities in the Araucanía Region, Chile

In the Araucanía Region there are no studies on the seroprevalence of leptospirosis in horses. Serological samples from 100 draft horses from Mapuche communities of four communes in the region were analyzed using the microMAT technique. The seroprevalence was 35% for at least one serovar of Leptospira spp. being the most frequent serovars canicola (22%), grippotyphosa (21%), hardjo (13%) and pomona (10%). It was evident that the equine populations studied are exposed to infection by Leptospira spp. and reveal a potential risk of transmission to their owners.

Shedding and Genetic Diversity of Leptospira spp. From Urban Stray Dogs in Klang Valley, Malaysia

Leptospirosis is an endemic zoonoses of global proportions. Stray dogs have been postulated to play a role in disease transmission; however, supporting information are still limited. Roaming behavior may not only predispose the dogs to infection, but could also contribute to disease spread. In this study, the susceptibility of urban stray dogs in shedding Leptospira spp. was determined. Blood, urine, and tissue samples of kidney and liver were collected from 100 dogs from 2 animal control facilities. Serological testing using microscopic agglutination test (MAT) were performed on blood against 20 leptospiral serovars with a cut-off titre of ≥ 1:100. Samples were cultured onto semi-solid Ellinghausen and McCullough modified by Johnson and Harris (EMJH) media. Isolates were identified using molecular polymerase chain reaction (PCR) using 2 primers (16s rRNA and LipL32) and hyperimmune serum (HIS) MAT. The seroprevalence for the dogs positive for leptospirosis was 32% (n=32/100) with the following detected serovars: Javanica (n=13), Bataviae (n=10), Icterohaemorrhagiae (n=3), Autumnalis (n=2), Canicola (n=1), Pyrogenes (n=1), Copenhageni (n=1), and Australis (n=1). Six Leptospira spp. isolated were procured from urine (n=2), kidney (n=2) and liver (n=2). All 6 isolates belonged to L. interrogans, a pathogenic variant of Leptospira spp. Serotyping and phylogenetic analysis suggested serovar Bataviae (n=5) and serovar Canicola (n=1). Presence of vaccinal serovars (Icterohaemorrhagiae and Canicola) suggested potential post-vaccination antibodies but the predominance of non-vaccinal serovars (Javanica and Bataviae) indicate the possibility of current infection or post-exposure. Isolation of Leptospira spp. directly from urine sample not only suggested an active infection but highlighted the potential shedding capability among these stray dogs. These findings further strengthen speculations that urban stray dogs could play a role in transmission and dissemination of leptospirosis through their constant movement. The urine of infected dogs may contaminate the environment, posing a major public health threat.

New Insights on Leptospira Infections in a Canine Population from North Sardinia, Italy: A Sero-Epidemiological Study.

Simple SummaryLeptospirosis is a widespread zoonosis caused by pathogenic spirochaetes of the genus Leptospira. Pathogenic leptospires live in the kidneys of different mammalian species and are excreted in the environment with the urine. The infection of humans is mainly caused by direct contact with infected animals or indirectly by contact with a contaminated environment. The aim of this study was to perform a sero-epidemiological survey to assess the presence of antibodies against Leptospira serovars in a representative sample of kennel and owned dogs from a selected area of Sardinia Island. In addition, kidney homogenates from rodents collected from the same study area were also analyzed by culture-based and real-time PCR-based testing methods. Higher antibody titers were observed against Leptospira Icterohaemmorrhagiae, which is believed to be responsible for the majority of severe cases of leptospirosis in humans. The detection of pathogenic Leptospira serotypes in dogs from northern Sardinia may represent a potential risk of infection for humans and contribute to the spread of the bacteria in the environment. Public health strategies to control possible Leptospira outbreaks should be implemented to prevent the disease from becoming a major medical and veterinary problem in this region.Leptospirosis is a widespread zoonosis recognized as a re-emerging infectious disease in a wide variety of animal species, including humans and dogs. No data exist regarding the presence of Leptospira species in the canine population of Sardinia Island. This study reports the first sero-survey for leptospirosis in kennel and owned dogs from six areas of the north of Sardinia. Sera from 1296 dogs were tested by microscopic agglutination test (MAT) specific for nine different serovars that are known to be well widespread in the Mediterranean environment. Moreover, kidney homogenates from rodents collected from the study area were also analyzed by LipL32 real-time PCR and multi-locus sequence type (MLST) on the basis of the analysis of seven concatenated loci. A total of 13% of the examined sera (95%CI: 11–15) tested positive for one or more serovars of Leptospira MAT detected; antibodies for serogroup Icterohaemorrhagiae (57%; 95%CI: 49–65) were the most common, followed by serovars Bratislava (22%; 95%CI: 16–28), Canicola (14%; 95%CI: 9–19), and Grippotyphosa (7%; 95%CI: 3–11). MLST analyses on isolates from rodents identified L. interrogans and L. borgpetersenii genomospecies. Different serovars belonging to pathogenic Leptospira serogroups are circulating in dogs from the island. Moreover, data obtained from rodents, indicated that rodents likely act as reservoir of spirochetes. Further sero-epidemiological studies are needed in order to obtain data from other collection sites in Sardinia and to increase the information on Leptospira species circulating in this area.

Clinical, diagnostic, and epidemiological features of a community-wide outbreak of canine leptospirosis in a low-prevalence region (Maricopa County, Arizona).

To describe clinical, diagnostic, and epidemiological features of an outbreak of leptospirosis in dogs in Maricopa County, Ariz, from January 2016 through June 2017. 71 case and 281 control dogs. Cases were classified as confirmed, probable, suspect, or not a case on the basis of medical record data that fulfilled clinical, diagnostic, and epidemiological criteria. Potential exposures were assessed by owner survey. For the case-control investigation, control dogs were recruited through owner completion of a July 2017 survey. Summary statistics and ORs for case dog lifestyle factors were reported. 54 dogs were classified as confirmed and 17 as probable cases. For 4 dogs of a household cluster (5 confirmed and 3 probable), the highest microscopic agglutination titer was for serovar Djasiman (Leptospira kirschneri detected by PCR assay), and for 13 dogs of a community outbreak (49 confirmed and 14 probable cases), the highest titer was for serovar Canicola (Leptospira interrogans detected by PCR assay). The 44 case dogs included in the case-control investigation were 7.7 (95% CI, 3.5 to 16.7) and 2.9 times (95% CI, 1.3 to 6.6) as likely as control dogs to have visited dog daycare or to have been kenneled overnight at a boarding facility, respectively, 30 days prior to the onset of clinical signs or diagnosis. Diagnostic and epidemiological findings indicated 2 outbreaks. Transmission where dogs congregated likely propagated the community outbreak. Outbreaks of leptospiral infections can occur in regions of low prevalence, and a dog's exposure to areas where dogs congregate should be considered when making Leptospira vaccination recommendations.

Serum Antileptospiral Agglutinins in Sea Turtles (Eretmochelys imbricata and Chelonia mydas) from the Gulf of Mexico

Leptospiral agglutinins have been measured in several species of chelonians in studies dating back to the1960s. However, despite the fact that sea turtles are one of the most charismatic and endangered groups of chelonians, only a single study has measured leptospiral antibodies in this group. Serum samples collected from hawksbill sea turtles (Eretmochelys imbricata) (n = 10) and green sea turtles (Chelonia mydas) (n = 10) from two locations from the Gulf of Mexico were analyzed to detect Leptospira interrogans using the microagglutination test. Hawksbill and green sea turtles tested positive to five and seven serovars, respectively, with the serovars Grippotyphosa, Bratislava, and Canicola presenting a prevalence ≥50% in both species. Titers ranged from 1:50 to 1:400. These and previous results demonstrate that terrestrial, freshwater, and sea turtles are exposed to Leptospira at some stage of their life. The role of reptiles in the epidemiology, persistence, and transmission of leptospirosis is still controversial; however, there is evidence that some species of turtles can disseminate them in the environment. The detection of Leptospira is of sanitary importance as it is a cosmopolitan zoonotic disease. Preventive measures should be taken by people working in sea turtle camps and aquariums to control and reduce their risk of exposure.

New strategies for Leptospira vaccine development based on LPS removal.

Pathogenic spirochetes from genus Leptospira are etiologic agents of leptospirosis. Cellular vaccines against Leptospira infection often elicit mainly response against the LPS antigen of the serovars present in the formulation. There is no suitable protein candidate capable of replacing whole-cell vaccines, thus requiring new approaches on vaccine development to improve leptospirosis prevention. Our goal was to develop a whole-cell vaccine sorovar-independent based on LPS removal and conservation of protein antigens exposure, to evaluate the protective capacity of monovalent or bivalent vaccines against homologous and heterologous virulent Leptospira in hamster. Leptospire were subjected to heat inactivation, or to LPS extraction with butanol and in some cases further inactivation with formaldehyde. Hamsters were immunized and challenged with homologous or heterologous virulent serovars, blood and organs were collected from the survivors for bacterial quantification, chemokine evaluation, and analysis of sera antibody reactivity and cross-reactivity by Western blot. Immunization with either heated or low LPS vaccines with serovar Copenhageni or Canicola resulted in 100% protection of the animals challenged with homologous virulent bacteria. Notably, different from the whole-cell vaccine, the low LPS vaccines produced with serovar Canicola provided only partial protection in heterologous challenge with the virulent Copenhageni serovar. Immunization with bivalent formulation results in 100% protection of immunized animals challenged with virulent serovar Canicola. All vaccines produced were able to eliminate bacteria from the kidney of challenged animals. All the vaccines raised antibodies capable to recognize antigens of serovars not present in the vaccine formulation. Transcripts of IFNγ, CXCL16, CCL5, CXCL10, CXCR6, and CCR5, increased in all immunized animals. Conclusion: Our results showed that bivalent vaccines with reduced LPS may be an interesting strategy for protection against heterologous virulent serovars. Besides the desirable multivalent protection, the low LPS vaccines are specially promising due to the expected lower reatogenicity.

Sero-prevalence of Leptospira spp. in Household and Stray Dogs by Microscopic Agglutination Test

Background: Leptospirosis is a zoonotic disease of worldwide significance in human beings and many animals. This zoonotic disease causes infection in dogs and other pet animals and these animals can influence human’s health. Given the unknown prevalence of leptospirosis in dogs in our area, this study was performed to investigate the sero-epidemiology of leptospirosis and evaluate the seroprevalence of Leptospira serovars in both household and stray dogs by microscopic agglutination test (MAT). Methods: Serum samples of 90 dogs in two household and stray groups (45 dogs for each group) were collected. Specimens were examined by MAT (in accordance with the procedure recommended by WHO) against antigens of serovars Canicola, Grippotyphosa, Icterohaemorrhagiae, Pomona, Hardjo, Autumnalis, and Ballum. Results: In total, 6.7% of (n=6) dogs (1 stray and 5 household dogs) had a serum titer of 1:100 or more against Leptospira serovars. Dominant serovars were Canicola (8.9%), Grippotyphosa (2.2%), and Pomona (2.2%), respectively. The antibody titer against more than one serovar was observed only in one dog. The sero-prevalence was 11.1% in household dogs and 2.2% in stray dogs. Since 4 pet dogs had been vaccinated recently, it seems that the actual percentage of infection in household dogs must be just 2.2% and actual infection in dogs including stray dogs is approximately 4.4% in Tabriz. Conclusion: Fortunately, the rate of infection in Tabriz is low and this can be due to special geographical and climatic conditions, regular and annual vaccination of household dogs against this disease, and lack of suitable conditions for the growth and survival of such micro-organisms in the environment

Carriage of pathogenic Leptospira in carnivores at the wild/domestic interface.

The carriage of pathogenic Leptospira was investigated by PCR in 51 wild carnivores, 20 domestic dogs with outdoor access, and 27 free-roaming domestic cats sampled in periurban Barcelona (NE Spain). Overall prevalence was 7.7%, with DNA confirmed in 3/30 common genets (Genetta genetta) (serovars Icterohaemorraghiae and Sejröe), 1/9 red foxes (Vulpes vulpes) (Canicola) and 2/27 cats (Icterohaemorraghiae). Though most of the dogs were vaccinated against Leptospira, DNA of the serovar Canicola was detected in the urine of 25% of the vaccinated animals, and the serovar Icterohaemorraghiae in one non-vaccinated dog.

Presence of Antibodies Against Leptospira interrogans Serovar hardjo in Serum Samples from Cattle in Ukraine.

The article presents data on serological studies of 573 sera samples of cattle that were collected from the farms affected by leptospirosis in different regions of Ukraine in the period of 2014–2015. Samples were investigated by the microscopic agglutination test (MAT), which was conducted within eight serological groups of Leptospira and nine serovars: Sejroe (serovars polonica and hardjo), Hebdomadis (serovar kabura), Tarassovi (serovar tarassovi), Pomona (serovar pomona), Grippotyphosa (serovar grippotyphosa), Canicola (serovar canicola), Icterohaemorrhagiae (serovar copenhageni), and Australis (serovar bratislava). The circulation of L. interrogans serovar hardjo among cattle has been observed in all 11 regions of Ukraine investigated within 25.8–60.0% of the leptospirosis-positive serum samples in these regions. Antibodies in the cattle sera against serovar hardjo (serogroup Sejroe) were detected in 139 of the 370 cows reacting positively in MAT. Overall, they were detected in 24.3% animals out of the total of 573 cows investigated. These are the preliminary results, however, in our opinion, they should allow to include the serovar hardjo in a standard panel of strains for MAT in Ukraine.

Leptospira seroprevalence in owned dogs from Spain

Leptospira is a widespread zoonosis that has been linked to transmission between dogs and humans. The main purposes were to determine the seroprevalence of anti-Leptospira serum antibody and to identify the most common serovars in dogs in Spain. This is a cross-sectional study with 1,310 records of canine Leptospira testing data from Spain since 2015 to 2017. Inclusion criteria were individual cases with MAT test results for 8 serovars (Bratislava, Icterohaemorrhagiae, Australis, Pomona, Grippotyphosa, Autumnalis, Canicola and Saxkoebing) and to have the zip code data. Three hundred and thirty-eight samples (25.8%; 95%CI 23.6–28.4) were seropositive (≥1:100). According to geographic areas, North had the highest seroprevalence (38.0%; 95%CI 28.9–47.1) followed by South (29.4%; 95%CI 20.1–38.8), Center (28.6%; 95%CI 24.3–33.0), Mediterranean (22.3%; 95%CI 19.1–25.6) and Northwest (22.2%; 95%CI 7.9–36.4). Seropositivity (MAT ≥1:100) was most common to serovars Icterohaemorrhagiae (19.4%; 95%CI 17.2–21.5) and Bratislava (8.5%; 95%CI 7.0–10.0), followed by Grippotyphosa (7.2%; 95%CI 5.8–8.6), Australis (6.4%; 95%CI 5.0–7.7), Autumnalis (5.0%; 95%CI 3.8–6.2), Pomona (4.5%; 95%CI 3.3–5.6), Canicola (3.4%; 95%CI 2.4–4.4) and Saxkoebing (0.8%; 95%CI 0.3–1.3). An association was found between positivity (MAT ≥1:100) and males (P = 0.003) and dogs that were 6 years old or older were at higher risk of exposure (P = 0.001; OR 4.61; 95%CI 1.86–11.43). This study has shown that dogs in Spain are commonly exposed to Leptospira infection and points out the necessity to control the prevalence of this severe widespread zoonosis in dogs and humans.

Epidemiological relevance of dogs for the prevention of Toxoplasma gondii, Neospora caninum and Leptospira spp.

This study evaluated the seroprevalence of Toxoplasma gondii, Neospora caninum and Leptospira spp. in dogs from Foz do Iguaçu, Paraná, Brazil. Indirect immunofluorescent antibody test was used to detect antibodies anti-T.gondii and anti-N. caninum. Immunoenzymatic assay and microscopic serum agglutination were used for screening antibodies anti-T.gondii and anti-Leptospira spp., respectively. The results were: 67.02% of the samples reactive for T.gondii and 1.38% for N. caninum, both without statistically significant variables. For Leptospira spp. the results indicated seroprevalence of 23.11%. The analysis of the variables without distinction of serovar showed association for intrinsic characteristics as breed, age, nutritional status and dog category. The extrinsic variables as city region and access to the street presented association (p<0.05). The most prevalent serovars were: Canicola 59.47%; Bratislava 13.07% and Butembo 15.68%. Variables that make up the adjusted multiple analysis model using Leptospira spp. were: age, breed and nutritional status; serovar Canicola, sex, nutritional status and area (p<0.05); serovar Bratislava, lymphadenomegaly and presence of fleas (p<0.05). Given the results obtained, dogs can be used as sentinels for toxoplasmosis and leptospirosis in Foz do Iguaçu and other cities with similar outcomes. In addition, preventive measures should be taken by health authorities because they are zoonoses and humans are also at risk.

Evidence of Pathogenic Leptospira Infection in a Free-Ranging Andean Fox (Lycalopex culpaeus) from Central Chile

We found evidence of infection and shedding of Leptospira serovars Ballum and Canicola in the Andean fox (Lycalopex culpaeus) in Chile. We used PCR to demonstrate the presence of Leptospira DNA and microagglutination tests to identify serovars.

Relation of reproductive disturbance in sheep and Leptospira interrogans serovar Icterohaemorrhagiae infection: Impacts on cellular oxidation status

This study evaluated the seropositivity of Brucella abortus and Leptospira interrogans in ewes with reproductive disturbances in southern Brazil and verified the creatine kinase (CK) activity and oxidation status via assessment of superoxide dismutase, glutathione peroxidase and glutathione transferase in serum of seropositive animals for L. interrogans serovar Icterohaemorrhagiae. For Leptospira infection 381 animals with clinical history of reproductive disturbance from Planalto Serrano de Santa Catarina (Brazil) were analyzed, showing an occurrence for L. interrogans of 20.2% from which 81.8% were seropositive for L. interrogans Icterohaemorrhagiae. Serovars Wolfii, Grippothyphosa, Bratislava, Canicola and Butembo were also identified. In the case of B. abortus, positive cases were identified by buffered acidified antigen, finding 14 positive samples, but none of them were positive after a second test (2-mercaptoethanol), showing the absence of relationship between infection with B. abortus and abortion in the tested individuals. Serum reactive oxygen species (ROS) levels and CK activity were found higher in animals positive for Leptospira infection, presenting higher titrations (1:320) than non-infected individuals. Serum glutathione peroxidase activity was higher in positive animals with titrations 1:160 and 1:320, while serum glutathione S-transferase was higher in positive individuals only for titrations 1:320. Serum superoxide dismutase showed lower activity in infected animals with titrations of 1:320. Our results show the region of Planalto Serrano de Santa Catarina with a high occurrence levels of sheep infected by L. interrogans serovar Icterohaemorrhagiae, from which animals with high titrations (1:320) present oxidative stress elicited by excessive ROS production, triggering the stimulation of antioxidant systems to counter this excess. In summary, ovine with higher titrations (1:320) present oxidative damage that can contribute to disease pathophysiology.

Seroprevalence and distribution of leptospirosis serovars among wet market workers in northeastern, Malaysia: a cross sectional study

BackgroundLeptospirosis is a zoonotic disease associated with occupations which exposed workers to environments contaminated with urine of infected animals. The objective of this study was to determine the seroprevalence of leptospirosis among wet market workers in Kelantan.MethodsA cross sectional study was conducted in two main wet markets in Kelantan and 232 wet market workers were randomly selected. Blood samples were analysed for microscopic agglutination test (MAT) against 20 live leptospirosis reference serovars. MAT titres of 1:100 or more were considered as seropositive.ResultsIt was found that the overall seroprevalence for leptospirosis among the respondents was 33.6% (95% CI = 27.5, 39.7). The samples were tested positive against serovars Melaka (IMR LEP 1), Terengganu (IMR LEP 115), Sarawak (IMR LEP 175), Copenhageni (IMR LEP 803/11), Hardjobovis (IMR LEP 27), Australis, Autumnalis, Bataviae, Canicola, Grippotyphosa, Hardjoprajitno, Icterohaemorrhagiae, Javanica, Pyrogenes, Terrasovi, Djasiman, Patoc and Pomona. The predominant serovars was Autumnalis (18.2%).ConclusionWet markets workers were at risk for leptospirosis infection evidenced by high seroprevalence of leptospirosis in this study. Further research need to be conducted to determine factors that favours infection in this groups.