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

China ; Humans ; Serogroup ; Shigella

China ; Humans ; Meningococcal Infections ; Serogroup

This research and development of MenB meningococcal vaccines includes two technical routes: outer membrane vesicle (OMV) vaccines and recombinant protein vaccines. This article intends to review the development, production and application of MenB meningococcal OMV vaccines in order to provide a reference for the development of MenB meningococcal OMV vaccine in China.
Antigens, Bacterial ; Humans ; Meningococcal Infections/prevention & control* ; Meningococcal Vaccines ; Neisseria meningitidis, Serogroup B ; Serogroup ; Vaccines, Synthetic

The efficacies of six commercial disinfectants were evaluated by using Salmonella enterica serovar Typhimurium under simulated natural conditions such as sub-zero temperature, short disinfecting time, and surface type (uneven or smooth). We used a suspensionmodel test to determine the disinfecting efficacy under varying contact times (1, 5, 10, and 30 min) and temperatures (25℃, 4℃, 0℃, and −10℃). The bactericidal effect according to surface structure was measured by using a carriermodel test at 25℃ and −10℃. The effective concentrations of each disinfectant were fixed to give a disinfecting effect within a short time (< 1 min) at 25℃ and −10℃. The suspension model results revealed that bactericidal efficacy significantly dropped at low temperature for most of the disinfectants used; a sodium dichloroisocyanurate product showed the strongest efficacy. In the carrier test, bacterial load on a wooden surface was more difficult to remove than that on a stainless-steel surface. The results show that commercial disinfectant products vary in their disinfecting efficacy, which is affected by several field factors including temperature, contact time, and carrier material. Environmental conditions and surface type for disinfection should be considered prior to selecting an optimal disinfectant in the field.
Bacterial Load ; Disinfectants* ; Disinfection ; Salmonella enterica* ; Salmonella* ; Serogroup* ; Sodium

Legionella pneumophila are intracellular pathogens, associated with human disease, attributed to the presence and absence of certain virulent genes. In this study, virulent gene loci (lvh and rtxA regions) associated with human disease were determined. Thirty-three cooling tower water isolates, isolated between 2004 to 2006, were analyzed for the presence of these genes by PCR method. Results showed that 19 of 33 (57.5%) of the L. pneumophila serogroup 1 isolates have both the genes. Six (18.2%) of the isolates have only the lvh gene and 2 (6.1%) of the isolates have only the rtxA gene. However, both genes were absent in 6 (18.2%) of the L. pneumophila isolates. The result of our study provides some insight into the presence of the disease causing L. pneumophila serogroup 1 in the environment. Molecular epidemiological studies will provide better understanding of the prevalence of the disease in Malaysia.
L ; Malaysia ; Genes ; Legionella pneumophila serogroup 1 ; occurrence

OBJECTIVE: To establish and modify quantitative real-time polymerase chain reaction (qPCR)-based serotyping assays to distinguish 97 pneumococcal serotypes. METHODS: A database of capsular polysaccharide ( cps) loci sequences was generated, covering 97 pneumococcal serotypes. Bioinformatics analyses were performed to identify the cps loci structure and target genes related to different pneumococcal serotypes with specific SNPs. A total of 27 novel qPCR serotyping assay primers and probes were established based on qPCR, while 27 recombinant plasmids containing serotype-specific DNA sequence fragments were constructed as reference target sequences to examine the specificity and sensitivity of the qPCR assay. A panel of pneumococcal reference strains was employed to evaluate the capability of pneumococcal serotyping. RESULTS: A total of 97 pneumococcal serotyping assays based on qPCR were established and modified, which included 64 serotypes previously reported as well as an additional 33 serotypes. Twenty-seven novel qPCR serotyping target sequences were implemented in the pneumococcal qPCR serotyping system. A total of 97 pneumococcal serotypes, which included 52 individual serotypes and 45 serotypes belonging to 20 serogroups, could not be identified as individual serotypes. The sensitivity of qPCR assays based on 27 target sequences was 1-100 copies/µL. The specificity of the qPCR assays was 100%, which were tested by a panel of 90 serotypes of the pneumococcal reference strains. CONCLUSION A total of 27 novel qPCR assays were established and modified to analyze 97 pneumococcal serotypes.
Real-Time Polymerase Chain Reaction ; Serotyping ; Streptococcus pneumoniae/genetics* ; Serogroup

Vibrio cholerae (V. cholerae) serotype O1 or O139 is the etiological agents of cholera. These bacteria are responsible for gastrointestinal infections or more rarely bacteremia in patients with an underlying disease, leading to life-threatening complications. A 73-year-old man presented to the hospital with fever and vomiting. Blood cultures grew non-O1/non-O139 V. cholerae. In this case, clinical improvement and microbiological eradication were achieved due to early appropriate antibiotic therapy. These results suggest that early antibiotic therapy allowed a good outcome in diabetic patient infected with V. cholerae . To our knowledge, this is the first case of primary bacteremia caused by non-O1/non-O139 Vibrio cholera in Korea.
Aged ; Bacteremia* ; Bacteria ; Cholera ; Fever ; Humans ; Korea ; Serogroup ; Vibrio cholerae* ; Vibrio* ; Vomiting

Salmonella (S.) enterica and Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens. Here, we report the prevalence of S. enterica and STEC in feces of 316 zoo animals belonging to 61 species from Chile. S. enterica and STEC strains were detected in 7.5% and 4.4% of animals, respectively. All Salmonella isolates corresponded to the serotype Enteritidis. To the best of our knowledge, this is the first report of S. Enteritidis in the culpeo fox (Lycalopex culpaeus), black-capped capuchin (Sapajus apella) and Peruvian pelican (Pelecanus thagus) and the first STEC report in Thomson's gazelle (Eudorcas thomsonii).
Animals ; Animals, Zoo* ; Chile* ; Feces ; Prevalence* ; Salmonella enterica* ; Salmonella* ; Serogroup ; Shiga-Toxigenic Escherichia coli*

BACKGROUND: Sequence type 131 (ST131) O25b serogroup Escherichia coli, producing CTX-M type extended-spectrum β-lactamase (ESBL), is a major clone involved in worldwide pandemic spread in both community- and healthcare-associated infections. Recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a routine tool for the identification of bacteria in many laboratories. This study aimed to assess the performance of MALDI-TOF MS for the screening of ESBL-producing E. coli ST131 in a rapid, inexpensive, and simple way. METHODS: A total 26 clinical E. coli, isolated from blood between 2013 and 2014, were used. The characteristics are ST131-O25b ESBL producers (n=6), ST131-O16 ESBL producers (n=4), non-ST131 ESBL producers (n=11), and non-ST131 non-ESBL producers (n=5). Specific biomarker peaks to distinguish the ST131 clonal group from others were investigated by MicroIDSys (ASTA, South Korea) and ASTA Tinkerbell 2.0 software. RESULTS: A peak at 9,713 m/z peak is useful to screen for ST131 E. coli, regardless of serogroup O25 or O16, showing a sensitivity of 100%, specificity of 56.2%, positive predictive value of 58.8%, and negative predictive value of 100% when using a relative intensity cutoff of 15%. CONCLUSION: We can screen for ST131 E. coli using MicroIDSys (ASTA), MALDI-TOF MS in a rapid, inexpensive, and simple way. However, other confirmatory tests are needed to confirm ST131 E. coli due to the low specificity of this method.
Bacteria ; Clone Cells ; Escherichia coli* ; Escherichia* ; Mass Screening ; Mass Spectrometry* ; Methods ; Pandemics ; Sensitivity and Specificity ; Serogroup