使用顯微凝集試驗、乳膠凝集試驗，與LipL32重組蛋白質構成的酵素連結免疫吸附法調查臺灣地區鼠類的鉤端螺旋體抗體盛行率

Leptospirosis is a major threat in tropical and subtropical countries as well as temperate countries. The disease is caused by pathogenic Leptospira species and considered to be an emerging or re-emerging disease in many countries of the world. Infection in domestic animals and wildlife can lead to economic loss and pose a potential spread to the communities. In the present study recombinant LigB protein is employed in latex agglutination test, which is a cross reacting lipoprotein able to detect acute infection caused by any pathogenic leptospiral serovars. It was employed for serodiagnosis of leptospirosis. The 46KDa 6X His tagged LigB protein, obtained by IPTG induction of recombinant E. coli M15 cells containing the N-terminal region of LigB gee in P QE30 expression vector, was purified by Ni-NTA affinity chromatography and adsorbed on latex bead surface for performing latex agglutination test against Leptospirosis suspected wildlife field sera. A total of 80 wildlife sera samples were collected, including 27 wild feline sera samples (18 tigers, 8 lions, and 1 jaguar) obtained from Chhatbir zoo, Chandigarh, 42 serasamples ( 8 tigers, 4 lions and 6 leopards, 2 cheethals, 1 black buck, 12 buffaloes and 9 zoo staff) sera and 3 live rodents ) were received from Jodhpur zoo Rajasthan, 8 sera samples (4 tigers, 3 leopards, 1 lion) sera from Van Vihar National park, Bohpal, Madhya Pradesh and 3 sera samples (2 lions,and 1 tiger) received from Biwani Mini zoo, Haryana, India. The result showed that sera were tested positive by rLigB based LAT, which were reconfirmed using microscopic agglutination test (MAT). The results from LAT were in concordance with MAT. In conclusion, rLigB based LAT is a rapid, pen site, reliable diagnostic tool of high sensitivity and specificity, under laboratory and field conditions, for the detection of Leptospirosis .

A One Health approach to investigating the health and prevalence of zoonotic pathogens in snow leopards, sympatric wildlife, domestic animals and humans in the South Gobi Desert in Mongolia

Summary Leptospirosis is an important infectious disease of animals and humans caused by the pathogenic leptospires which are classified into one species of Leptospira interrogans containing over 212 serovars. This study was conducted to determine the prevalence of Leptospira-induced abortions in Tabriz (north-west of Iran) dairy herds and to determine the pathogenic Leptospira serovars responsible. From May 2008 through August 2010, 16 (21.05%) of 76 submissions (fetuses and placentas) to the Large Animal Clinic of the Veterinary Faculty at the University of Tabriz were diagnosed as positive to L. interrogans serovars by PCR. In contrast, only 9 (11.85%) of 76 dam's sera were diagnosed as positive to leptospirosis by the microscopic agglutination test (MAT). Two out of 9 animals were seropositive to serovar pomona, one animal to serovar icterohaemorrhagiae, two animals to canicula, three animals to both pomona and grippotyphosa, and one animal to the both canicula and grippotyphos. Moreover, the prevalence of Leptospira-induced abortions was high in the aged cows and advanced pregnancies (7-9 months). However statistical difference was not observed among these groups or different periods of pregnancy. In conclusion, serovar pomona induced abortions were determined to be more common leptospiral abortions in cattle in Tabriz and combination of PCR protocol with the MAT test would be more effective than the single test for etiological diagnosis of bovine abortions.

Summary Leptospirosis is a worldwide zoonosis caused by Leptospira interrogans. This study was conducted to evaluate serologic and bacteriologic findings of leptospirosis in clinically-suspected cows. 380 sera and 33 urine samples were collected from 6 industrial dairy farms in Tehran suburb, from December 2004 to June 2005. The prevalence of disease was determined by microscopic agglutination test (MAT), enzyme-linked immunosorbent assay (ELISA), direct dark-field microscopic (DFM) examination, indirect fluorescent antibody test (IFAT), microbiologic cultural isolation technique and polymerase chain reaction (PCR). Antibodies were detected by MAT at least against one serovar of L. interrogans in 55 sera (14.5%) among 380 samples at a dilution of ≥ 1:100. L. interrogans serovar icterohaemorrhagiae was the most prevalent serovar. Leptospiral antibodies were detected by ELISA in 85 sera (22.4%) among 380 samples. Four (12.1%) of 33 urine samples were suspected by DFM examination and no positive sample by IFAT was observed. Leptospires could be isolated from none of the 33 samples taken from industrial farms. In this study, positive controls were detected at a dilution of ≥ 2000 leptospires per each ml of urine sample by PCR. Therefore, no DNA from serum and urine samples were collected from 6 industrial dairy farms could be detected by this method. It seems that, to increase the accuracy in the diagnosis of the disease, using a range of reliable techniques and comparing the results is important in reaching final conclusion.

Leptospirosis is a zoonotic disease caused by bacterial infection, Leptospira interrogans. The bacteria usually infect many kinds of wild animals and humans as well. There was an extraordinary outbreak of leptospirosis in humans in Yogyakarta in 2011. Therefore, it is necessary to investigate the seroprevalences of leptospirosis in cows, especially in the districts of Bantul and Kulon Progo in order to determine the possible role(s) of the cows in the spread of leptospirosis among other animals and humans. In this research, the diagnostic method was conducted by using microscopic agglutination test (MAT). Bovine sera samples were obtained from several farms in some areas of the districts of Bantul and Kulonprogo. The MAT was conducted on 150 sera samples of cows from districts of Bantul and was on 200 samples from Kulonprogo. Seroprevalences of leptospirosis in the cows were 18.67 % ( 28/150 ) and 14.5% (29/200) from Bantul and Kulonprogro districts, respectively. Mostly, serovar tarassovi, hardjo, icterohemorrhagiae and batavia were detected in cows from both Bantul and Kulonprogo districts. Antibody titers were obtained ranged from 1:100, 1:400 and 1:1600.

Leptospirosis is a spirochaetal infection that possesses a broad host range affecting almost all mammals. In the present study, the microscopic agglutination test (MAT) was compared with recombinant LigA/B antigen-based point-of-care diagnostics such as the in-house IgM dot ELISA dipstick test (IgM- DEDT) and the latex agglutination test (LAT) for the serodiagnosis of human leptospirosis. The comparison of the MAT with these two point–of-care diagnostics was performed using the MAT as the gold standard test and using Bayesian latent class modelling (BLCM), which considers all diagnostic tests as imperfect. The N-terminal conserved region of the LigA/B protein spanning the first to fifth big tandem repeat domains (rLigA/BCon1-5) was employed as a serodiagnostic marker in both of the bedside assays. A total of 340 serum samples collected from humans involved in high risk occupations were screened using the MAT, IgM DEDT and LAT. During the early phase of leptospirosis, BLCM analysis showed that the IgM DEDT and LAT had similar sensitivities (99.6 (96.0–100)) and (99.5 (95.2–100)), respectively, while the single acute phase MAT had the lowest sensitivity (83.3 (72.8–91.3)). Both the IgM DEDT and the LAT may be superior to the single acute phase MAT in terms of sensitivity during the early phase of infection and may be suitable for the early diagnosis of leptospirosis. However, BLCM analysis revealed that the use of both acute and convalescent samples substantially increased the sensitivity of the final MAT (98.2% (93.0–99.8%)) as a test to diagnose human leptospirosis. Both the IgM DEDT and LAT can be employed as bedside spot tests in remote locations where the MAT is not easily accessible.

Farmers in Bali live in close contact to pigs, a setting which favours transduction of leptospirosis to humans. Since little is known about the prevalence of different Leptosipro (L.) serovars in Bali, a serosurvey was initiated to identify Leptospira serovars predominating in domestic pigs. In 1999, a total of 484 sera from pigs on 138 farms in two geographically distinct provinces of Bali (Gianyar and Tabanan), Indonesia, were collected. Agglutinins against 7 serovars of pathogenic Leptospira were determined using the microscopic agglutination test (MAT). The overall percentage of sera giving titres of >= 100 against at least one serovar was 27.1%. Prevalences varied between the provinces Gianyar (30.1%) and Tabanan (22.4%) but didn't differ significantly. Prevalence of Seroreactivity for individual serovars was 1.0% (L. grippotyphoso), 2.1% (L. torossovi), 1.2% (L. copenhageni), 16.3% (L. pomona), 5.4% (L. hardjo), and 9.3% (L. brotislava). Agglutinins against L. conicola could not be detected. High titres (>= 400) were almost exclusively directed against L. pomona, implying that L. pomona is the predominant Leptospira serovar in Balinese pigs

Comparison of an in-house latex agglutination test with IgM ELISA and MAT in the diagnosis of leptospirosis

This study aimed to develop latex agglutination test (LAT) using recombinant leptospiral immunoglobulin-like protein (LigB) (rLigB) antigen and compare its diagnostic efficacy with LAT using conventional heat-killed leptospiral antigen and microscopic agglutination test (MAT) in diagnosing bovine leptospirosis. The PCR-amplified 1053-bp ligB gene sequences from Leptospira borgpetersenii Hardjo serovar were cloned in pET 32 (a) vector at EcoRI and NotI sites and expressed in BL21 E. coli cells as fusion protein with thioredoxin (-57 kDa) and characterized by SDS-PAGE and immunoblot. Out of 390 serum samples [cattle (n = 214), buffaloes (n = 176)] subjected to MAT, 115 samples showed reciprocal titre≥100 up to 1600 against one or more serovars. For recombinant LigB protein/antigen-based LAT, agglutination was observed in the positive sample, while no agglutination was observed in the negative sample. Similarly, heat-killed leptospiral antigen was prepared from and used in LAT for comparison with MAT. A two-sided contingency table was used for analysis of LAT using both the antigens separately against MAT for 390 serum samples. The sensitivity, specificity and positive and negative predictive values of recombinant LigB LAT were found to be 75.65, 91.27, 78.38 and 89.96 %, respectively, and that of heat-killed antigen-based LAT were 72.17, 89.82, 74.77 and 88.53 %, respectively, in comparison with MAT. This developed test will be an alternative/complementary to the existing battery of diagnostic assays/tests for specific detection of pathogenic Leptospira infection in bovine population.

The aim of this study was to survey antibodies against Leptospira spp. and to isolate Salmonella spp. in a flock of sheep in the Municipality of Itapira, SP, Brazil. For this, the presence of antibodies against Leptospira spp. was verified by the microscopic agglutination test (MAT) and, to obtain cultures of Salmonella spp., the retal swabs were inoculated into enrichment broths. Of 115 analysed animals, 44 (38.26%) were positive, 23 (20.00%) to serovar Hebdomadis 15 (13.04%) to serovar Icterohaemorrhagiae and six (22.5%) to serovar Pomona. No animals were positive to Salmonella spp. These findings suggest that sheep can be an infection source of Leptospira spp. for humans and the absence of positive results in the Salmonella spp. analysis do not ensure that the pathogen is not present infecting humans and animals. Health professionals in Brazil need to be more committed to actions of preventive medicine in rural communities, in order to get success in control of important zoonoses such as leptospirosis and salmonellosis.

Summary Leptospirosis is a zoonosis of worldwide distribution, caused by Leptospira interrogans. It is a well known cause of bovine reproductive losses such as abortion, infertility, stillbirth and birth of weak calves. In this research, the relationship between the seroprevalence rate of Leptospira spp. infection and abortion in industrial dairy farms of Hamedan province, Iran was studied. A total of 80 blood samples were taken from aborted cows in six dairy farms. Sera were tested for antibodies against 6 serovars of Leptospira interrogans (hardjo, pomona, canicola, grippotyphosa, icterohaemorrhagiae and ballum) using microscopic agglutination test (MAT). Antibodies were detected in 18 (22.5%) of the aborted cows, including 17 (21.25%) against L. canicola and 1 (1.25%) against L. pomona. It is concluded that dogs (shepherd and stray) and wild carnivores may have an important role to maintain and transmit the L. canicola infection to the cattle population in this region, therefore, vaccination of cattle and shepherd dogs should be applied.

To carry out a retrospective analysis of Leptospira microscopic agglutination test (MAT) results performed at Tifton Veterinary Diagnostic and Investigational Laboratory in Georgia from June 2015 to December 2023. Test records for MAT against 7 Leptospira interrogans serovars (Autumnalis, Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona) were retrieved from submissions among cattle, dogs, goats, equids, pigs, and wildlife/exotic species. Further categorization was performed by state and health conditions for seropositive animals, including by breed purpose for cattle (beef, dairy, and dual purpose) and body weight groups for dogs (large, medium, and small). Across all species, the seropositivity rate was 52.3% (552 of 1,055), and the most frequently detected MAT antibodies were against serovar Autumnalis (60.3%; 95% CI, 56.1% to 64.4%), followed by Icterohaemorrhagiae (52.7%; 95% CI, 48.5% to 57.0%). Equids had the highest seropositivity rate (82.5% [47 of 57]) followed by pigs (80.0% [16 of 20]), cattle (54.1% [351 of 649]), dogs (45.6% [131 of 287]), goats (23.3% [7 of 30]), and exotic species (0% [0 of 12]). The highest MAT titer (1:12,800) was detected in a Florida dairy cow against Pomona; a Georgia dog against Autumnalis, Grippotyphosa, and Pomona; and a South Carolina Paint Horse against Pomona. In the southeastern region of the US, the most frequently detected MAT titers were against serovar Autumnalis in dogs, equids, goats, and pigs, while in cattle, Autumnalis was the second most frequent serovar after Icterohaemorrhagiae. The frequent and/or exclusive detection of Autumnalis and Bratislava MAT titers supports the inclusion of these 2 serovars in leptospirosis vaccines and MAT panels used in veterinary diagnostic laboratories across the US.

Canine leptospirosis is a serious public health concern. This study aims to investigate the feasibility of conserved first to fifth domains of recombinant Leptospira immunoglobulin like protein B antigen (rLigBCon1-5) as a serodiagnostic marker for detecting canine leptospirosis. A total of 340 unvaccinated canine serum samples were screened using microscopic agglutination test (MAT) and rLigBCon1-5 based immunoglobulin G (IgG) indirect-enzyme-linked immunosorbent assay (I-ELISA). Further, 60 vaccinated canine sera were screened using MAT and rLigBCon1-5 based latex agglutination test (LAT). Microscopic agglutination test results revealed seropositivity of 28.6%. The relative sensitivity, specificity, and accuracy of IgG I-ELISA in comparison to MAT were 100%, 96.0%, and 97.2%, respectively. Out of 60 vaccinated sera, 46 sera reacted with MAT alone, and eight sera reacted by both tests, while six sera were non-reactive with both tests. Anti-LigB antibodies were detected in eight canine sera by rLigBCon1-5 based LAT. In five LAT reactive sera, agglutinins of locally circulating Leptospira serovars Grippotyphosa (n=4) and Australis (n=1) were detected. In three LAT reactive sera, agglutinins against Icterohaemorrhagiae (n=3) produced due to natural infection were present. Immunoglobulin G based indirect ELISA assay (IgG I-ELISA) can be employed as an alternative test instead of MAT. rLigBCon1-5 based LAT detected anti-LigB antibodies in eight vaccinated sera where the vaccine failure occurred partially or totally due to the limited efficacy spectrum of Nobivac® RL and cold chain breakage. This vaccine could not provide cross-protection against locally circulating Leptospira serovars. The recombinant LigBCon1-5 antigen based LAT possesses capability of differentiating infected from vaccinated individuals (DIVA capability) when employed as a pen-side test for detecting canine leptospirosis.

BACKGROUND: The prevalence and incidence of end-stage renal disease are high in Taiwan. Acute leptospirosis infection often causes renal tubulointerstitial disease, but the association of occult leptospirosis and renal disease is unclear. The aim of this study is to define the possible association between occult leptospirosis infection and chronic kidney disease (CKD). METHODS: In this prospective observational cohort study, 371 patients with CKD and 100 residents without CKD in the same community were included. Microscopic agglutination test (MAT) was employed to detect occult leptospirosis. Both renal progression and microalbuminuria were also monitored during a follow-up period of 42 months. RESULTS: Low prevalence of positive MAT is found in normal and CKD subjects. There was no significant difference in amount of microalbuminuria between MAT positive and negative subjects (527.52 ± 125.18 vs. 728.2 ± 216.23, mg/day, P ＞ 0.05). Logistic analysis for CKD progression did not show different CKD progression between MAT positive and negative groups. CONCLUSION: The prevalent rates of positive MAT in normal and CKD subjects were similar. There was also no difference in microalbuminuria and CKD progression between MAT positive and negative subjects. Our findings suggested that occult leptospirosis might not be associated with development and progression of CKD in North Taiwan.

Leptospirosis is a zoonosis of global distribution caused by infection with pathogenic spirochaetes of the genus Leptospira. Humans are accidental hosts and usually become infected through contact with water or soil contaminated by the urine of infected animals such as rodents, dogs, cattle and pigs. In developing countries such as India, leptospirosis is often underdiagnosed because of its protean clinical manifestations leading to significant morbidity and mortality. It occurs as a self-limited illness in 85% to 90% of the cases and icteric leptospirosis or Weil's syndrome, a more serious, potentially fatal syndrome which occurs in 5% to 10% of the cases. Microbiological diagnosis of leptospirosis aims at demonstrating the leptospires, by culturing them or by demonstrating an appreciable antibody response to them. A definite diagnosis of leptospirosis is based either on isolation of the organism from the patient or on seroconversion or a rise in antibody titre in the MAT. Leptospires may be visualized in clinical material by DGM or by IF or light microscopy after appropriate staining. The sensitivity of blood cultures is low; hence culture is primarily used for retrospective diagnosis. There are numerous serological tests available for diagnosis of leptospirosis like Macroscopic agglutination test (MSAT), Indirect fluorescent antibody test (IFAT), Sensitised erythrocyte lysis test (SEL), Complement fixation test (CFT), Enzyme Linked Sorbent Assay (ELISA), Microcapsule agglutination test (MCAT), Lepto-Dipstick, Latex agglutination test, Dried Latex agglutination test (Lepto Tek Dri-Dot), but they are only genus specific. To identify the specific serovar Microscopic agglutination test (MAT) or culture has to be done. The various available options for a diagnosis of leptospirosis have been explored in this article. A thorough literary search was done in the various published data available- pub med search was done as well as