Microagglutination Test Research Articles

Serosurvey of Leptospira spp. in captive non-human primates in Spain

Leptospirosis is a worldwide zoonotic disease caused by serovars of Leptospira spp. that can infect a wide range of wild and domestic species, highlighting non-human primates (NHPs) as one of the most susceptible taxonomic groups. The aim of the present study was to determine the seroprevalence and potential risk factors associated with exposure to Leptospira spp. in captive NHPs in Spain. Between 2007 and 2021, sera were collected from 258 NHPs in 16 zoos and wildlife rescue centers (WRCs), and tested for antibodies to Leptospira spp. using the modified microagglutination test (MAT). Anti-Leptospira spp. antibodies were detected in 73 (28.3 %) of the 258 NHPs evaluated. Seropositivity was found in 61.0 % (25/41) of the species analyzed and in 87.5 % (14/16) of the sampled centers. Sera seropositive for six different serovars of Leptospira spp. were detected, with L. Grippotyphosa being the most prevalent. Seroprevalence was found to be significantly higher in Hominidae (61.8 %; P < 0.001) compared to other NHP families tested. To the author’s knowledge, the present study is the largest serosurvey of Leptospira spp. conducted in NHPs in Europe and also reports for the first time exposure to Leptospira spp. in nine NHP species, expanding the host range for this zoonotic bacterium. Our results indicate high and widespread seropositivity of Leptospira spp. in NHPs kept in captivity in Spain, which may be of conservation and animal health concern. This study supports the need to include captive NHPs in monitoring programs to evaluate the exposure of these species to Leptospira spp. in captive centers.

Investigation of Leptospirosis Agents in Cattle and Humans.

Leptospirosis, a global zoonotic disease, causes serious morbidity and mortality generally in low-income societies. This study aimed to investigate the prevalence of Leptospira serovars in cattle and high-risk human populations. This study investigated the presence of pathogenic Leptospira serogroups in the blood and kidney samples of cattle arriving at the Erzurum Meat and Milk Institution for slaughter between April and July, and between September and December 2022, and in the serum samples of humans. Kidney and serum samples from 289 cattle and serum samples from 100 individuals from at-risk occupational groups (58 farmers, 25 veterinarians and 17 butchers) were collected. As a control, 100 human blood samples were collected from civil servants who had no contact with animals. Microagglutination testing was used to investigate Leptospira serogroups in bovine sera, real-time polymerase chain reaction (PCR) for Leptospira DNA in kidney samples, and microagglutination testing and enzyme-linked immunosorbent assays for Leptospira antibodies in human blood serum samples. Microagglutination test in 4.5% of cattle; Leptospira DNA was positive in 0.7%. Six strains of Leptospira interrogans, two of Bratislava, one of Pomana and one of Icterohaemorrhagiae were found in cattle, as well as one strain of Leptospira kirschneri Dadas. In humans, two Icterohaemorrhagiae, one Hebdomadis and one Dadas serovar were detected in both the risk group and the control group. Using ELISA, antibody positivity was found to be 14.0% in the risk group and 11.0% in the control group. The seroprevalence of Leptospira spp. in cattle in Erzurum, Türkiye, is relatively high. In this region, the risk of encountering Leptospira in the normal population is as high as in the risk group.

Isolation of Virulent Leptospira Serogroup Australis Field Strains from Symptomatic Dogs for Canine Leptospiral Vaccine Development.

Leptospirosis is a widespread zoonosis caused by spirochaetes belonging to the pathogenic species of Leptospira, which are classified into more than 25 serogroups and 250 serovars. Vaccination can prevent the disease in dogs but offers incomplete efficacy because of a lack of cross-protection between serogroups. The aim of this study was to validate a robust recruitment and sampling process, with the objectives of isolating and typing circulating Leptospira pathogenic strains and then selecting those of proven virulence and pathogenicity for vaccine development. Blood and urine samples from dogs with clinical syndromes compatible with acute leptospirosis were sterilely collected and transported to a reference laboratory for a micro-agglutination test (MAT), PCR, and bacterial isolation. Isolated strains underwent molecular typing using RNA16S, variable-number tandem repeat (VNTR), and pulsed-field gel electrophoresis (PFGE). Subtyping was performed using core genome multilocus sequence typing (CgMLST). Among 64 included dogs, 41 had MAT and/or PCR results compatible with Leptospira infection, and 14 Leptospira strains were isolated. Based on molecular typing, 11 isolates were classified as L. interrogans serogroup Australis, serovar Bratislava, and 3 as serogroup Icterohaemorrhagiae, serovar Icterohaemorrhagiae. CgMLST subtyping revealed a diversity of clonal groups (CGs) distributed in several regional clusters. Besides validating a robust recruitment and sampling process, this study outlines the value of combining PCR and serological testing when suspecting leptospirosis and the usefulness of implementing molecular typing methods to identify circulating field strains. It also confirms the epidemiological importance of the Australis serogroup and allows for the collection of different highly pathogenic strains for vaccine development.

Assessment of serum microagglutination test based on flagellar antigens for differentiating between S. Abortusequi and Salmonella Typhimurium infections

Assessment of serum microagglutination test based on flagellar antigens for differentiating between <i>S</i>. Abortusequi and <i>Salmonella</i> Typhimurium infections

Molecular and serological investigation of Francisella tularensis among wild animals in Yamaguchi prefecture.

Francisella tularensis is an intracellular gram-negative bacterium known as the causative agent of tularemia, which can be transmitted to humans by direct contact with wild animals or by tick bites. Although F. tularensis is highly pathogenic, its recent prevalence in Japan is underreported due to the small number of reported cases. To clarify the current situation of F. tularensis in wild animals, we conducted surveillance on various species of wild animals in Yamaguchi prefecture. In this study, we screened 809 samples collected from 90 Japanese black bears, 105 Japanese monkeys, 168 sika deer, 205 wild boars, and 84 bats. For seroprevalence analysis, we tested 177 serum samples from 75 black bears and 102 monkeys using the microagglutination test. The results showed that serums from five black bears exhibited slight agglutination. Western blot was performed as a confirmatory test on these five samples, but no positive signals were detected. Additionally, molecular surveillance was conducted using DNA extracted from 464 whole blood and 168 tissues, targeting the gene encoding 23 KDa hypothetical protein by real-time PCR and outer membrane protein A gene by conventional PCR. No positive samples of F. tularensis were detected by either real-time or conventional PCR. Although we did not detect any F. tularensis-positive samples through serological and molecular analyses, continuous surveillance studies are necessary since sporadic human cases have been reported in Japan.

Accuracy of rapid lateral flow immunoassays for human leptospirosis diagnosis: A systematic review and meta-analysis.

In the last two decades, several rapid lateral flow immunoassays (LFIs) for the diagnosis of human leptospirosis were developed and commercialized. However, the accuracy and reliability of these LFIs are not well understood. In this study, we aimed to evaluate the accuracy of leptospirosis LFIs as well as the factors affecting the test efficiency using systematic review and meta-analysis. Original articles reporting the accuracy of human leptospirosis LFIs against microagglutination tests (MAT) or immunofluorescent assays (IFA) were searched from PubMed, Embase, and Scopus, and selected as per pre-set inclusion and exclusion criteria. A total of 49 data entries extracted from 24 eligible records published between 2003 and 2023 were included for meta-analysis. A meta-analysis was performed using STATA. The quality of the included studies was assessed according to the revised QUADAS-2. Only nine studies (32.1%) were considered to have a low risk of bias and no concern for applicability. Pooled sensitivity and specificity were calculated to be 68% (95% confidence interval, CI: 57-78) and 93% (95% CI: 90-95), respectively. However, the ranges of sensitivity (3.6 - 100%) and specificity (53.5 - 100%) of individual entries are dramatically broad, possibly due to the heterogeneity found in both study designs and LFIs themselves. Subgroup analysis demonstrated that IgM detection has better sensitivity than detection of IgG alone. Moreover, the test performance seems to be unaffected by samples from different phases of infection. The pooled specificity of LFIs observed is somewhat acceptable, but the pooled sensitivity is low. These results, however, must be interpreted with caution because of substantial heterogeneity. Further evaluations of the LFIs with well-standardized design and reference test will be needed for a greater understanding of the test performance. Additionally, IgM detection type should be employed when leptospirosis LFIs are developed in the future.

Infection and re-infection of Leptospira spp. in stray dogs and cats from Bogota, Colombia.

Leptospirosis is a re-emerging zoonosis that is under-reported in tropical countries, and canines can be a potential reservoir of the disease. The objective of this study was to diagnose Leptospira spp. that is actively infected and re-infected in stray dogs and cats from Bogota, D.C., Colombia. A sample of 200 animals, including dogs and cats from the animal protection programs of Bogota, Colombia, were used in this study. Blood was collected from these animals for serum and DNA analysis. Conventional polymerase chain reaction (PCR) was performed using the 16s rRNA primer set, and higher-quality amplification products were sequenced by Sanger. For serodiagnosis, a group of PCR-positive samples was tested using the microagglutination test (MAT). The overall PCR positivity of stray dogs and cats was 56%, 52.9%, and 65.3% in dogs and cats, respectively. The MAT seropositivity was 77.3%, and only dogs showed titers higher than 1:400. Canicola, Icterohaemorrhagiae, Pomona, Hardjo Prajitno, and Canicola and Hardjo prajitno were the serogroups associated with dogs and cats, respectively. Phylogenetic analysis revealed that the strains belonging to Leptospira interrogans serovars related to isolated samples of American, European, and Asian bats (Myotis myotis), dogs, and bovines of American origin. These results showed that stray dogs and cats were previously exposed to different serovars of Leptospira spp. and re-infected with other serovars that actively participated in the transmission cycle. These findings highlight the importance of actively diagnosing infectious animals to design effective intervention strategies.

Four Cases of Laboratory Acquired Q Fever: Lessons from the Past and a Brief Review of Literature

The aim of this communication is to highlight the dangers of Q fever outbreaks in laboratories attempting isolation of Coxiella burnetii (C. burnetii) and other rickettsiae without Bio Safety Level (BSL)-3 facilities. This series is reported for the benefit of Microbiologists who evince interest in Rickettsial research. Four cases of Laboratory-acquired Q fever is presented among the laboratory personnel in a tertiary care teaching Hospital in Karnataka in 1977, which has not been reported yet. Four persons (one Lecturer, one animal technician and two M.Sc. students) who assisted in blood collection from slaughtered domestic livestock from butcheries and/or participated in the isolation of C. burnetii by guinea pig inoculation became seropositive for Q fever. The presence of antibodies to C. burnetii was demonstrated by two specific serological tests, Micro Agglutination Test (MAT) and Complement Fixation Test (CFT) for Q fever. They responded well to treatment with oxytetracycline, the drug of choice. It should be known that even microscopic demonstration of C. burnetii and other rickettsiae in the ectoparasites is hazardous, due to liberation of infective aerosol in the process. A safe commercial Q fever vaccine for laboratory and farm workers is presently available in Australia alone. Therefore, preventive measures like use of BSL-3 facility in the laboratory as well as animal house, wearing N95 face masks and protective clothing (PPE) are some of the essential precautions to follow so as to prevent laboratory acquired Q fever infection, which is an important occupational hazard.

Fatal acute undifferentiated febrile illness among clinically suspected leptospirosis cases in Colombia, 2016-2019.

Acute undifferentiated febrile illness is a common challenge for clinicians, especially in tropical and subtropical countries. Incorrect or delayed diagnosis of febrile patients may result in medical complications or preventable deaths. Common causes of acute undifferentiated febrile illness in Colombia include leptospirosis, rickettsioses, dengue fever, malaria, chikungunya, and Zika virus infection. In this study, we described the acute undifferentiated febrile illness in postmortem patients reported as suspected cases of leptospirosis through the national leptospirosis surveillance in Colombia, 2016-2019. We retrospectively analyze human fresh and formalin-fixed tissue samples from fatal suspected leptospirosis cases reported by the Public Health Laboratories in Colombia. Leptospirosis confirmation was made by immunohistochemistry, real-time polymerase chain reaction (PCR) in the tissue samples. In some cases, the serum sample was used for confirmation by Microagglutination test (MAT). Simultaneously, tissue samples were tested by PCR for the most common viral (dengue, Zika, and chikungunya), bacterial (Brucella spp., and Rickettsia spp.), and parasitic (malaria). Fresh tissue samples from 92 fatal suspected leptospirosis cases were reported to the National Reference Laboratory from 22/32 departments in Colombia. We confirmed leptospirosis in 27% (25/92) of cases. Other pathogens identified by real-time PCR were Brucella spp. (10.9%), Rickettsia spp. (14.1%), and dengue (2.2%). Dengue (6.9%), hepatitis (3.5%), and Yellow Fever cases (2.2%) were detected by the pathology. All patients were negative for chikungunya and Plasmodium spp. Most cases were classified as undifferentiated febrile illnesses (45.7%; 42/92). This study underscores the importance of early and accurate recognition of leptospirosis to prevent mortalities. Moreover, it draws attention to the existence of other febrile syndromes in Colombia, including rickettsiosis and brucellosis, that currently lack sufficient human surveillance and regular reporting. Expanding laboratory surveillance to include viruses such as Hantavirus, Mayaro virus, Oropouche virus, and West Nile virus is crucial.

Detección de infección por Brucella canis en perros de raza Pit Bull en Turquía

Brucella canis infection is an often neglected but important zoonotic disease. This study aims to determine its seroprevalence in Pit Bull dogs from the Western Region of the Turkish Anatolian Peninsula. In the Province of Manisa, 2 mL blood samples were taken from the antebrachial region of 35 Pit Bull dogs using sterile K2EDTA (3.6 mg) blood tubes, and the samples were analyzed using both the mercaptoethanol (ME) microagglutination test and B. canis–specific PCR techniques. Of the 35 dogs tested by 2–ME RSAT, 13 (37.14%) tested positive and 22 (63%) tested negative. Of the 13 dogs that tested positive for 2–ME RSAT, 8 (22.85%) were female, and 5 (14.28%) were male. Subsequent PCR analysis of all samples revealed that 7 (20%; 7/35) of the samples that tested positive for 2–ME RSAT were actually B. canis–specific PCR positive. These findings suggest that B. canis is present in Pit Bull dogs, although they provide a general idea of the disease's prevalence of the disease in the region. Multicentre studies with larger numbers of cases in different groups of Pit Bulls, such as healthy, patient and risk groups, are needed to provide comprehensive evidence.

Francisella tularensis: a zoonotic pathogen among wild rodents and arthropods - a possible threat in future

Francisella tularensis is a Gram-negative coccobacillus and an aerobic bacterium. It causes a zoonotic disease called tularemia in humans. Four subspecies have been found in F. tularensis as F. tularensis subsp. Tularensis (Type A strains), F. tularensis subsp. Holarctica (Type B strains), F. tularensis subsp. mediasiatica, and F. tularensis subsp. Novicida. Rearing rabbits and different kinds of rodents as pets are becoming popular in Sri Lanka, veterinarians need to be knowledgeable on emerging pathogens such as F. tularensis, to diagnose the disease within a short time. Therefore, the objective of this paper is to update veterinarians on possible emerging infections to improve the health of pets and to minimize possible zoonotic infections. The clinical outcome caused by Francisella is a debilitating febrile disease in humans. Francisella has been isolated from hundreds of animal species in the world. Being a diverse host range, associated ecological factors relating transmission of Francisella in the environment is largely unknown. F. tularensis type A was reported to be common in North America while occasionally found in Europe. Type B was found commonly in the Northern hemisphere and in Australia. Tularemia is a sporadic disease, and a small infectious dose is required for an infection in humans. The clinical signs and symptoms of tularaemia depend on the route of infection. Six types of clinical forms were identified as ulceroglandular, glandular, oropharyngeal, oculoglandular, pneumonic and typhoidal in humans. Diagnosis of tularemia in humans is based on epidemiology, clinical findings and laboratory confirmation. Microagglutination test, indirect immunofluorescence assay (IFA) and Enzymelinked immunosorbent assay ELISA are widely used as diagnostic tests. Several conventional and qPCR have been optimized to detect the organism in clinical samples. Antimicrobials such as aminoglycosides, tetracycline, quinolones, and chloramphenicol were used to minimize clinical complications. Utilization of treated water, usage of gloves on handling wild rabbits and rodents, thorough cooking of bush meat, usage of insect repellents, protection of stored food from rodents, wearing masks, ticks-free clothes, keeping away from weeds, cleaning pets from external parasites have been identified as the main preventive strategies against tularaemia in human. No commercial vaccine is found in the market yet against F. tularensis. This can be an emerging and threatening disease in the future with ongoing changes in arthropod parasites in the ecosystem followed by climatic changes in the world.

A cross-sectional investigation of Leptospira at the wildlife-livestock interface in New Zealand.

There has been a recent upsurge in human cases of leptospirosis in New Zealand, with wildlife a suspected emerging source, but up-to-date knowledge on this topic is lacking. We conducted a cross-sectional study in two farm environments to estimate Leptospira seroprevalence in wildlife and sympatric livestock, PCR/culture prevalence in wildlife, and compare seroprevalence and prevalence between species, sex, and age groups. Traps targeting house mice (Mus musculus), black rats (Rattus rattus), hedgehogs (Erinaceus europaeus) and brushtail possums (Trichosurus vulpecula) were set for 10 trap-nights in March-April 2017 on a dairy (A) and a beef and sheep (B) farm. Trapped wild animals and an age-stratified random sample of domestic animals, namely cattle, sheep and working dogs were blood sampled. Sera were tested by microagglutination test for five serogroups and titres compared using a Proportional Similarity Index (PSI). Wildlife kidneys were sampled for culture and qPCR targeting the lipL32 gene. True prevalence in mice was assessed using occupancy modelling by collating different laboratory results. Infection profiles varied by species, age group and farm. At the MAT cut-point of ≥ 48, up to 78% of wildlife species, and 16-99% of domestic animals were seropositive. Five of nine hedgehogs, 23/105 mice and 1/14 black rat reacted to L. borgpetersenii sv Ballum. The sera of 4/18 possums and 4/9 hedgehogs reacted to L. borgpetersenii sv Hardjobovis whilst 1/18 possum and 1/9 hedgehog reacted to Tarassovi. In ruminants, seroprevalence for Hardjobovis and Pomona ranged 0-90% and 0-71% depending on the species and age group. Titres against Ballum, Tarassovi and Copenhageni were also observed in 4-20%, 0-25% and 0-21% of domestic species, respectively. The PSI indicated rodents and livestock had the most dissimilar serological responses. Three of nine hedgehogs, 31/105 mice and 2/14 rats were carrying leptospires (PCR and/or culture positive). True prevalence estimated by occupancy modelling in mice was 38% [95% Credible Interval 26, 51%] on Farm A and 22% [11, 40%] on Farm B. In the same environment, exposure to serovars found in wildlife species was commonly detected in livestock. Transmission pathways between and within species should be assessed to help in the development of efficient mitigation strategies against Leptospira.

A Canine Leptospirosis Clinical Case Due to Leptospira interrogans (Serogroup Icterohaemorrhagiae) in a Dog Kennel in Castelvetrano (Western Sicily, South Italy).

Leptospirosis is a worldwide widespread zoonosis caused by Leptospira genus. We report an acute leptospirosis case in a puppy housed at a municipal kennel and the subsequent diagnostic investigations carried out on all dogs housed in the kennel. Laboratory investigation included mainly a microagglutination test, real-time PCR, and multi-locus sequence typing (MLST) for Leptospira genus. Other agents of infection were excluded. The puppy resulted positive for Leptospira interrogans Icterohaemorrhagiae both with serological and molecular assays. All of the other 66 dogs in the kennel underwent clinical and laboratory investigations twice, 15 days apart. No other dog showed leptospirosis clinical signs. At the first sampling, eight dogs (12%) showed antibodies against Leptospira interrogans serogroup Icterohaemorragiae serovar Copenhageni. Real-time PCR on urine samples of seropositive dogs detected Leptospira spp. DNA in one sample, then identified as Leptospira interrogans serogroup Icterohaemorragiae by MLST. Fifteen days after, four of the previous seropositive dogs still showed antibodies against Leptospira spp. All urine samples collected from seropositive dogs were negative at real-time PCR. The study allowed the early confirmation of a Leptospirosis case and the identification of at least one asymptomatic carrier of pathogenic Leptospira spp. The prompt activation of all appropriate management measures allowed limiting and extinguishing the infection.

Leptospiral uveitis- "Transition 'from epidemic to endemic form" difficulties in laboratory confirmations.

Leptospirosis is a waterborne zoonotic disease that primarily causes systemic illness, followed by uveitis. After heavy flooding in Madurai district, an epidemic outbreak of systemic and ocular leptospirosis occurred in 1994. Our data shows a transition to endemicity after each epidemic. The aim of this study is to report the clinical signs, epidemic outbreaks, and persistent endemicity of leptospiral uveitis, as well as the diagnostic dilemmas associated with it. A retrospective analysis of clinical signs was conducted using medical records of leptospiral uveitis patients over a period of 27 years (1994-2020) in a tertiary care eye hospital. The clinical workup of uveitis included a detailed clinical history, systemic, and ophthalmic examination. Microagglutination tests (MATs) was done at the Centers for Disease Control and Prevention (CDC) in Atlanta and later in our regional laboratory. Serum samples were collected from human systemic leptospirosis cases and a small group of animals in and around Madurai. The first epidemic outbreak resulted in 200 seropositive patients. Subsequent epidemic outbreaks occurred in 1997, 1998, 2001, 2005, and 2012, with Madurai experiencing multiple outbreaks. However, the disease remained endemic, with 25-50 patients being observed per year in between the peaks. Ocular examination revealed acute non-granulomatous uveitis (94.9%), pan uveitis (59.8%), vitreous inflammatory reaction (55.4%), retinal vasculitis (29.5%), disc hyperemia (20.9%), and hypopyon. (16.2%). New serovars emerged every year, resulting in decreased sensitivity of the MAT. Over time, the MAT started to miss diagnoses. The persistent endemicity of leptospiral uveitis emphasizes the need for accessible diagnostic tests. The low performance of the MAT can be attributable to the use of an older panel. The incorporation of new isolates in the MAT by a national laboratory will improve the accuracy of diagnosis.

Demographic and clinical risk factors associated with severity of lab-confirmed human leptospirosis in Colombia, 2015-2020.

Leptospirosis is a common zoonoses and is a major global public health threat. Most cases are mild, typically presenting as a non-specific acute febrile illness. However, leptospirosis can have life-threatening manifestations, including pulmonary hemorrhage syndrome, and acute kidney injury. In Colombia, notification and lab-confirmation of suspected human cases are mandatory. However, little is known about the demographic and clinical factors associated with severe leptospirosis, which could help to reduce clinical complications and mortality. Our aim was to identify risk factors associated with severe leptospirosis, intensive care unit (ICU) admission, and mortality in lab-confirmed cases in Colombia, 2015-2020. We analyzed 201 lab-confirmed human leptospirosis cases by microagglutination test. We used a logistic regression to identify the demographic and clinical risk factors associated with severe leptospirosis, admission to ICU, and death. Most leptospirosis confirmed cases occurred in men (85.6%); the mean age was 36.7 years. We classified severe cases (43.3%) by clinical manifestations as renal (29.9%) and liver (27.4%) failure, multiple-organ failure (24.4%), septic shock (24.4%), Weil syndrome (18.4%), pulmonary hemorrhage (18.4%), and meningitis (2.5%), admitted to the ICU (30.3%), and fatal (8.5%). Clinical conditions associated with severe leptospirosis were dyspnea (OR: 5.54; 95% CI: 1.46 to 20.98), tachycardia (OR:9.69; 95% CI: 15.96 to 58.8), and rash (OR: 10.25; 95% CI: 25.01 to 42.08). We identified demographic characteristics and clinical symptoms associated with severe leptospirosis in Colombia. We hope these results can support clinicians in providing timely treatment to leptospirosis patients to avoid preventable medical complications or deaths.

Muş İlinde Görülen Tularemi Olgularının Retrospektif Değerlendirilmesi: 2011-2022

Objective: Tularemia is a bacterial disease of humans, wild and domestic animals. Recently, an increase in human tularemia cases has been observed in many countries worldwide. This study aimed to calculate the incidence of tularemia cases in Muş, determine the seasonal distribution of cases, and describe the socio-demographic and clinical characteristics of tularemia cases detected over a twelve-year period. Methods: Data from 162 patients diagnosed clinically and serologically with tularemia and admitted to health facilities in Muş province between 2011 and 2022 were retrospectively analysed. Results: In our study, among 162 tularemia patients with F. tularensis microagglutination test titres of 1/160 and above, the ratio of male and female cases was equal (50%), and the mean age was 24.51 years. In the twelve-year evaluation, there were two major epidemics, and the most cases were seen in 2018 with 37 cases. Most cases were observed in winter (38.3%) and autumn (25.3%). Oropharyngeal tularemia was the most common form (64.2%) among the cases evaluated. Similar disease was found in 33.3% of patients living in the same neighbourhood as the patients, and no mortality was observed in any of the patients. Conclusion: As the oropharyngeal form is the most common, contact with contaminated water should be questioned, rodent and tick populations should be monitored and detailed epidemiological studies should be conducted. We believe that hygiene and sanitation measures are important with regard to tularemia outbreaks.

Epidemiology of Leptospira spp. infection in a beef cattle area of Argentina.

Leptospirosis is an infectious disease caused by pathogenic Leptospira that affect humans and animals. This disease is complex and non-eradicable in nature. Therefore, the understanding of it is epidemiology in different environments is crucial to implement prevention and control measures. The prevalence of Leptospira infection in beef cattle farms is affected by multiple environmental, management and individual factors. In this study, a cross-sectional serological survey was carried on to estimate the prevalence of Leptospira antibodies in beef cattle in Tandil and Ayacucho Departments (Buenos Aires Province) and to identify risk factors and spatial clusters associated with seropositivity. Using a probabilistic two-stage sampling, 25 farms and 15 animals per farm were selected. The Microagglutination Test was used to analize all serum samples. Bivariate and multivariate analyses were performed. Seventy-three out of 375 cows were seropositive, representing a positivity rate of 19.47% (95% CI: 10.51-28.42), with Sejroe and Pomona being the most reactive serogroups: 9.33% (95% CI: 6.26-12.41) and 8.27% (95% CI: 5.35-11.19), respectively. The prevalence in Ayacucho was 23.11% (95% CI: 10.05-36.17), and in Tandil, 14% (95% CI: 3.25-24.75). The animals from Ayacucho presented 2.01 (1.16-3.49) more chances of being positive compared with those from Tandil (p < 0.01). After the Generalized Linear Mixed Model (GLMM) with random effect of farm-level risk, the presence of lagoons (OR: 7.32, 95% CI: 1.68-31.8, p < 0.05) and undulating terrain (OR: 0.24, 95% CI: 0.07-0.74, p < 0.05) were associated with bovine leptospirosis. Four spatial clusters with higher rates of seropositivity were detected. A new GLMM was performed with the significant variables detected in the first GLMM and a new variable, "being inside the spatial cluster," being the only one that remained significant (OR: 9.58, 95% CI: 3.39-27.08, p < 0.0001). The animals inside the clusters belonged to farms with a greater presence of creeks (OR: 9.03, 95% CI: 3.37-24.18, p < 0.0001), higher accumulated rainfall (OR: 1.01, 95% CI: 1-1.01, p < 0.0001) and less undulating terrain (OR: 0.18, 95% CI: 0.10-0.35, p < 0.0001). We conclude that Leptospira is seroprevalent in beef cattle in Tandil and Ayacucho Departments, especially in the latter, where the largest cattle farms are located. Prevalence of seropositivity animals was associated with selected environmental risk factors.

Tularemia seroprevalence in humans in the region of the Hittite-Arzawa War (Inner Aegean Region), where the first biological weapon was used 3300 years ago.

: According to Egyptian records, tularemia emerged in the Canaan region, where it was first identified and spread to Anatolia over the Euphrates. It was used as an active biological weapon for the first time in the Hittite-Arzawa War in 1320-1318 BC. This study aimed to investigate the seroprevalence of tularemia in the Inner Aegean Region, which is thought to be the region where this war was fought 3300 years ago. Tularemia seropositivity in humans was investigated in 27 villages/neighborhoods in 3 districts in each of Manisa, Kütahya, and Uşak provinces. Before the study, the participants were informed about the disease via posters, and their blood samples were taken following filling out the questionnaire. Microagglutination tests were performed using in-house tularemia antigen and V plate for serological experiments. Rose-Bengal test was also performed on seropositive sera. Of the total of 410 people, 226 (55.12%) were male. The mean age of the volunteers was 43.72 years. The highest participation was from Kütahya Province. According to the results of the tularemia microagglutination test, seropositivity was detected in 6 cases. It was determined that all of the seropositive volunteers were in Kütahya. When the tularemia antibody titers were examined, seropositivity was determined at 1/20-1/160 titers. No positivity was detected in the Rose-Bengal test for cross-reaction. Kütahya has been identified as a risky region in terms of tularemia in the Inner Aegean Region. In order to use the resources in the country economically, first of all, the risk areas in terms of tularemia should be determined by serological studies in all regions. In order to increase awareness about the disease, physicians and filiation teams should be trained in risky areas. Surveillance studies should be conducted to identify and monitor possible sources in areas identified as risky.

Leptospira interrogans insoluble fraction as a potential antigen source for lateral flow immunochromatography

Leptospirosis is an emerging zoonosis that affects humans and animals. Immunochromatography rapid test is widely used for early diagnosis of leptospirosis, but with low sensitivity and specificity.To evaluate Leptospira interrogans insoluble fraction as a potential antigen source for lateral flow immunochromatography.Insoluble fraction derived from the crude bacterial extract was obtained by serial centrifugation. The polypeptide profile was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Immune reactivity of this fraction was assessed by Western Blotting and lateral flow immunochromatography (LFI). It was tested 160 microagglutination test (MAT)-positive sera from patients in the acute phase, 100 MAT-negative sera from patients with acute febrile illness, and 45 patients with other infectious diseases.There was a predominance of low molecular mass-polypeptide bands, ranging from 2 to 37 kDa. The antibody reactivity of theses polypeptides was found to range from 13-50%, especially between 10 and 38 kDa. Among MAT-positive sera of patients with leptospirosis in the acute phase, 97% were also positive in LFI, indicating high sensitivity. Among MAT-negative sera, all were negative in LFI, indicating high specificity. Only 2% of cross-reactivity was detected.The insoluble fraction can be a valuable antigen source for development of point-of-care diagnosis test for leptospirosis.

Diagnosis of Tularemia in a University Hospital in Turkey - 11-Year Evaluation

Objective: Francisella tularensis is a gram-negative coccobacillus and is the causative agent of tularemia, which is endemic in our country. The most common clinical form in Turkey is the oropharyngeal form. Sensitive lymphadenopathy is the most important finding, and fever, fatigue, and muscle and joint pain may occur in all clinical forms. Rodents such as rabbits, mice, and squirrels are the main reservoirs for humans, and the transmission is through contact with infected animal secretions and organs, contaminated water, and food. This study aimed to examine the socio-demographic, epidemiological, and clinical features of cases diagnosed with tularemia. Materials and Methods: Among the 583 patients whose serum samples were sent with a preliminary diagnosis of tularemia between 2011 and 2021, tularemia microagglutination test result (MAT) ≥1/160 titer, 18 years and older cases were included in the study. Results: A total of 24 tularemia cases were detected, with a mean age of 43.3±17 years, 10 (41.7%) were male, and 14 (58.3%) were female. The most common symptoms and findings among the cases were lymphadenopathy (LAP) (95.8%), fatigue (66.7%), sore throat, and high fever (58.3%), and the most common epidemiological history was living in a rural area (91.7%) and dealing with animal husbandry (66.7%), and 18 (75%) cases were referred to as oropharyngeal tularemia. More than half of the cases were detected between October and March. Conclusion: Tularemia is one of the endemic diseases in our country, and the epidemiological history should be taken carefully and kept in mind in the differential diagnosis of lymphadenopathy. Since it is the first tularemia study conducted in Malatya, it shows the epidemiological characteristics of the region.