Background and Objective: Leptospirosis is a disease caused by pathogenic Leptospira prevalent in tropical countries like the Philippines. Some studies have shown that the role of currently used antibiotics for leptospirosis is unclear since trials have found no significant benefit to patient outcomes compared to placebo. This signals the need for alternative therapies, such as herbal medicines, which may provide effective therapeutic regimens in treating this infection. In this study, we characterized the antibacterial potential of three Philippine herbal medicines against Leptospira interrogans. Methods: Crude methanolic extracts of Momordica charantia, Cassia alata, and Allium sativum were subjected to an optimized broth microdilution assay against L. interrogans, utilizing the resazurin-resorufin reaction as a cell proliferation and viability indicator. Results: The respective minimum inhibitory concentrations of the plants were found to be as follows: 1.25 mg/mL (M. charantia), 2.5 mg/mL (C. alata), and >5 mg/mL (A. sativum). Conclusions Among the three herbal medicines, M. charantia and C. alata proved to have antibacterial activity against L. interrogans. Given the promising potential of two of these plant extracts, exploring the use of other solvents to extract natural compounds from these plants, and discovering possible synergistic effects between these plants and conventional antibiotics may be worthwhile.
Leptospira interrogans ; Herbal Medicine

BACKGROUND AND OBJECTIVE

Leptospirosis is a disease caused by pathogenic Leptospira prevalent in tropical countries like the Philippines. Some studies have shown that the role of currently used antibiotics for leptospirosis is unclear since trials have found no significant benefit to patient outcomes compared to placebo. This signals the need for alternative therapies, such as herbal medicines, which may provide effective therapeutic regimens in treating this infection. In this study, we characterized the antibacterial potential of three Philippine herbal medicines against Leptospira interrogans.

Crude methanolic extracts of Momordica charantia, Cassia alata, and Allium sativum were subjected to an optimized broth microdilution assay against L. interrogans, utilizing the resazurin-resorufin reaction as a cell proliferation and viability indicator.

The respective minimum inhibitory concentrations of the plants were found to be as follows: 1.25 mg/mL (M. charantia), 2.5 mg/mL (C. alata), and >5 mg/mL (A. sativum).

Among the three herbal medicines, M. charantia and C. alata proved to have antibacterial activity against L. interrogans. Given the promising potential of two of these plant extracts, exploring the use of other solvents to extract natural compounds from these plants, and discovering possible synergistic effects between these plants and conventional antibiotics may be worthwhile.

Objective: To analyze the incidence of leptospirosis in Fujian province from 2015 to 2020 and provide the scientific evidences for the risk assessment, prevention and control of leptospirosis. Methods: The incidence data of leptospirosis in Fujian during 2015-2020 were collected from China Information System for Disease Control and Prevention for a descriptive analysis, and software ArcGIS 10.3.1 was used for spatial autocorrelation analysis, and rats were captured in 17 surveillance areas during the same period, and the rat organs were collected for pathogen culture, the level of Leptospira antibody was detected in serum samples of rats, healthy population and the serum samples of patients sent by the hospitals. The infection status of Leptospira in human and rats were analyzed. Results: The incidence of leptospirosis in Fujian showed a downward trend from 2015 to 2020. A total of 176 cases of leptospirosis were reported. There were obvious seasonality and bimodal distribution. The majority of cases were farmers, accounting for 49.43% (87/176). Most cases were aged 30-69 years (85.80%, 151/176). The male to female ratio of the cases was 3.51∶1 (137∶39). Spatial autocorrelation analysis showed that leptospirosis had high or low clustering areas. From 2015 to 2020, the average capture rate of rats in 17 surveillance areas was 6.96% (1 519/21 838), Rattus losea, Rattus flavipectus and Niviventer fulvescens were the main species. The average positive rate of Leptospira antibody in rats was 28.64% (252/880). Java and Autumnalis were the predominant serogroups, accounting for 56.75% (143/252) and 17.46% (44/252), respectively. The average positive rate of Leptospira antibody in healthy population was 16.13% (254/1 575), and Autumnalis and Australis were the predominant serogroups, accounting for 71.65% (182/254). The confirmation rate of leptospirosis in patient serum samples sent by the hospitals was 2.23% (188/8 431), Autumnalis (56.38%, 106/188) and Hebdomadis (19.68%, 37/188) were the major serogroups. Conclusions: The incidence of leptospirosis in Fujian showed a downward trend from 2015 to 2020, there were obvious area clustering and seasonality. The high clustering areas were mainly distributed in northern, western and central Fujian. Java and Autumnalis were the predominant serogroups in rats. The infection rate in healthy population decreased year by year. Autumnalis and Hebdomadis were the main serogroups in population in Fujian.
Animals ; Antibodies, Bacterial ; Female ; Humans ; Incidence ; Leptospira ; Leptospirosis/epidemiology* ; Male ; Rats ; Serogroup

Introduction: Leptospirosis is one of the neglected reemerging zoonoses that is of public health concern globally. The need to discover novel therapeutic alternatives for leptospirosis through screening for and elucidating the mechanism/s of the anti-leptospiral activity of plant extracts is therefore necessary. This study analyzes the optimized tube dilution technique and the BiologTM sole carbon utilization phenotype microarray as screening tool for anti-leptospiral activity of plant extracts. Methods: The suitability of the optimized tube dilution technique was evaluated by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and motility inhibition property of a plant extract and an antimicrobial control (pen G) against 4 dominantly circulating Leptospira serovars/serogroup in the Philippines. Likewise, the suitability of the BiologTM sole carbon utilization assay was evaluated using a plant extract and selected antimicrobials against L. interrogans serovar Manilae strain K64 and L. interrogans serovar Losbanos strain K37. Results: The MIC, MBC, and motility inhibition property of a plant extract and the antibiotic controls as well as its effect on the carbon utilization phenome of the Leptospira serovars gave consistent results, within and between several runs. With standard deviation = 0 for all serovars. The MIC and MBC of the antimicrobial control (pen G), the positive control, was 10 ug/ml. The growth control (leptospires without treatment), the negative control, showed presence of motile leptospires. The MIC and the MBC of the test plant extract was 250 ug/ml – 500 ug/ml. Results of the carbon utilization phenome or pattern of carbon utilization were consistent within the 3 replicates and between two runs. Conclusion The optimized tube dilution technique and the BiologTM sole carbon utilization assay is a potential in vitro screening tool for determining anti-leptospiral activity of plant extracts.
Leptospira ; Serogroup

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder of an unknown origin. The role of leptospirosis as a triggering factor for SLE is unknown. This paper reports an uncommon case of SLE following a leptospira infection. A 29-year-old female was referred due to fevers, myalgia, and facial edema with rash. Laboratory investigations revealed a hepatic dysfunction, significantly raised lactate dehydrogenase with marked leukopenia and thrombocytopenia. A diagnosis of leptospirosis was confirmed. The patient was treated with antibiotic therapy for leptospirosis. She developed dyspnea after one week. The echocardiogram revealed global hypokinesia with a decreased ejection fraction. A positivity of antinuclear, anti-DNA, and anti-Smith antibodies, together with clinical and laboratory improvement by steroid therapy, led to the diagnosis of SLE. This case highlights the presence of concurrent SLE and leptospirosis. As the symptoms of SLE are similar to leptospirosis, accurate diagnosis through high suspicion is essential for appropriate treatment.
Adult ; Antibodies ; Diagnosis ; Dyspnea ; Edema ; Exanthema ; Female ; Fever ; Humans ; Hypokinesia ; L-Lactate Dehydrogenase ; Leptospira ; Leptospirosis* ; Leukopenia ; Lupus Erythematosus, Systemic* ; Myalgia ; Myocarditis ; Thrombocytopenia

Leptospirosis is a febrile zoonotic disease. Routine diagnosis of leptospirosis is based on the detection of specific antibodies with serological tests. The aim of our study was to determine the usefulness of immunochromatographic assay (ICA), ImmuneMed Leptospira IgM Duo Rapid test kit from Korea, in rapid screening of acute leptospirosis in emergency cases with limited expertise. A total of 197 serum samples (93 positive, 104 negative) were selected randomly. The test has good diagnostic sensitivity 73% and specificity 90%. With positive predictive value of 87% and negative predictive value of 79%, this reassures patients have higher chance of correct diagnosis. This ICA is acceptable for screening of leptospirosis but confirmation with microscopic agglutination test should follow.
Agglutination Tests ; Antibodies* ; Diagnosis ; Emergencies ; Humans* ; Immunochromatography ; Immunoglobulin M* ; Korea ; Leptospira* ; Leptospirosis ; Mass Screening ; Sensitivity and Specificity ; Serologic Tests ; Zoonoses

Rodents are well-known reservoirs and vectors of many emerging and re-emerging infectious diseases, but little is known about their role in zoonotic disease transmission in Bhutan. In this study, a cross-sectional investigation of zoonotic disease pathogens in rodents was performed in Chukha district, Bhutan, where a high incidence of scrub typhus and cases of acute undifferentiated febrile illness had been reported in people during the preceding 4–6 months. Twelve rodents were trapped alive using wire-mesh traps. Following euthanasia, liver and kidney tissues were removed and tested using PCR for Orientia tsutsugamushi and other bacterial and rickettsial pathogens causing bartonellosis, borreliosis, human monocytic ehrlichiosis, human granulocytic anaplasmosis, leptospirosis, and rickettsiosis. A phylogenetic analysis was performed on all rodent species captured and pathogens detected. Four out of the 12 rodents (33.3%) tested positive by PCR for zoonotic pathogens. Anaplasma phagocytophilum, Bartonella grahamii, and B. queenslandensis were identified for the first time in Bhutan. Leptospira interrogans was also detected for the first time from rodents in Bhutan. The findings demonstrate the presence of these zoonotic pathogens in rodents in Bhutan, which may pose a risk of disease transmission to humans.
Anaplasma ; Anaplasma phagocytophilum ; Anaplasmosis ; Animals ; Bartonella ; Bartonella Infections ; Bhutan ; Communicable Diseases, Emerging ; Ehrlichiosis ; Euthanasia ; Humans ; Incidence ; Kidney ; Leptospira ; Leptospira interrogans ; Leptospirosis ; Liver ; Orientia tsutsugamushi ; Polymerase Chain Reaction ; Rodentia ; Scrub Typhus ; Zoonoses

Pharmacokinetic/pharmacodynamic (PK/PD) ratios of reference enrofloxacin (Enro-R) and enrofloxacin as HCl-2H₂O (Enro-C), as well as Monte Carlo simulations based on composite MIC₅₀ and MIC₉₀ (MIC, minimum inhibitory concentration) vs. Leptospira spp., were carried out in dogs after their intramuscular (IM) or oral administration (10 mg/kg). Plasma determination of enrofloxacin was achieved by means of high-performance liquid chromatography. Maximum plasma concentration values after oral administration were 1.47 ± 0.19 µg/mL and 5.3 ± 0.84 µg/mL for Enro-R and Enro-C, respectively, and 1.6 ± 0.12 µg/mL and 7.6 ± 0.93 µg/mL, respectively, after IM administration. Areas under the plasma vs. time concentration curve in 24 h (AUC₀₋₂₄) were 8.02 µg/mL/h and 36.2 µg/mL/h for Enro-R(oral) and Enro-C(oral), respectively, and 8.55 ± 0.85 µg/mL/h and 56.4 ± 6.21 µg/mL/h after IM administration of Enro-R and Enro-C, respectively. The PK/PD ratios and Monte Carlo simulations obtained with Enro-C, not Enro-R, indicated that its IM administration to dogs will result in therapeutic concentrations appropriate for treating leptospirosis. This is the first time enrofloxacin has been recommended to treat this disease in dogs.
Administration, Oral ; Animals ; Chromatography, Liquid ; Dogs ; Leptospira ; Leptospirosis ; Pharmacokinetics ; Plasma

Porcine parvovirus, Erysipelothrix (E.) rhusiopathiae, and Leptospira (L.) interrogans are considered major etiologic agents of reproductive failure in pigs, causing economic loss in the swine industry. In this study, the safety and immunogenicity of a new octavalent inactivated vaccine were evaluated. The vaccine contained inactivated porcine parvovirus, E. rhusiopathiae, and six L. interrogans serovars (Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona). Safety test results showed no notable side effects or clinical signs after vaccination in mice, guinea pigs, and sows. In addition, we assessed immunogenicity of the vaccine in 25 sows under field conditions. The vaccinated group (n = 20) had a significantly higher antibody level than the non-vaccinated group (n = 5). Moreover, the stillbirth rate decreased in piglets born from vaccinated sows, resulting in an increased fertility rate. The results of this study demonstrate that the new octavalent inactivated vaccine can be applied safely and effectively to improve reproductive performance in sows.
Animals ; Birth Rate ; Erysipelas* ; Erysipelothrix ; Guinea Pigs ; Leptospira* ; Leptospirosis ; Mice ; Parvovirus, Porcine* ; Serogroup ; Stillbirth ; Swine ; Vaccination

Leptospirosis, a zoonotic disease that is caused by many serovars which are more than 200 in the world, is an emerging worldwide disease. Accurate and rapid diagnostic tests for leptospirosis are a critical step to diagnose the disease. There are some commercial kits available for diagnosis of leptospirosis, but the obscurity of a species- or genus-specific antigen of pathogenic Leptospira interrogans causes the reduced sensitivity and specificity. In this study, the polysaccharide derived from lipopolysaccharide (LPS) of nonpathogenic Leptospira biflexa serovar patoc was prepared, and the antigenicity was confirmed by immunoblot and enzyme linked immunosorbent assay (ELISA). The performance of the rapid diagnostic test (RDT) kit using the polysaccharide as a diagnostic antigen was evaluated in Korea, Bulgaria and Argentina. The sensitivity was 93.9%, 100%, and 81.0% and the specificity was 97.9%, 100%, and 95.4% in Korea (which is a rare region occurring with 2 serovars mostly), Bulgaria (epidemic region with 3 serovars chiefly) and Argentina (endemic region with 19 serovars mainly) respectively. These results indicate that this RDT is applicable for global diagnosis of leptospirosis. This rapid and effective diagnosis will be helpful for diagnosis and manage of leptospirosis to use and the polysaccharide of Leptospira may be called as genus specific antigen for diagnosis.
Antigens, Bacterial/*immunology ; Argentina ; Bulgaria ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Leptospira/isolation & purification/metabolism ; Leptospira interrogans/isolation & purification/metabolism ; Leptospirosis/*diagnosis/microbiology ; Male ; Polysaccharides/*immunology ; Reagent Kits, Diagnostic/*standards ; Republic of Korea ; Sensitivity and Specificity