Susceptibilities of invasive Neisseria meningitidis strains to agents used for prophylaxis and to penicillin G

Antimicrobial susceptibility of 50 Neisseria meningitidis strains detected in Nova Scotia between 2004 and 2018 was determined. The isolates were cultured from sites that might prompt chemoprophylaxis (27 blood, 18 cerebrospinal fluid [CSF], 3 CSF–blood, and 2 conjunctiva). Minimal inhibitory concentrations (MICs) were determined to azithromycin, ciprofloxacin, minocycline, rifampin, trimethoprim–sulfamethoxazole, and penicillin G, using a diffusion gradient strip on Mueller–Hinton agar with 5% sheep blood in 5% CO2 for 20–24 hours. All isolates remained susceptible to azithromycin, ciprofloxacin, minocycline, and rifampin, but there was 26% resistance to trimethoprim–sulfamethoxazole. There was a rise in penicillin MIC of the isolates over the study period.

Isolasi dan Identifikasi Bakteri Streptococcus spp. pada Babi Penderita Porcine Respiratory Disease Complex

Streptococcus sp. merupakan salah satu penyebab primer terjadinya Porcine Respiratory Disease Complex (PRDC). Penelitian ini dilakukan untuk mendeteksi bakteri Streptococcus sp. di saluran pernapasan babi penderita PRDC serta distribusi bakteri Streptococcus sp. pada babi pra sapih dan pasca sapih. Sebanyak 43 sampel swab rongga hidung dikumpulkan dari babi yang menunjukkan gejala penyakit PRDC seperti depresi, anorexia, dyspnea, adanya eksudat dari rongga hidung, batuk/bersin, dan pembengkakan pada persendian. Sampel berasal dari peternakan babi di kabupaten Tabanan, kabupaten Badung, dan kabupaten Gianyar. Semua sampel ditanam pada media sheep blood agar dilanjutkan dengan uji pewarnaan Gram. Koloni yang dicurigai kemudian dilakukan uji primer berupa uji katalase dan uji oksidase serta uji biokimia dengan MRPV, TSIA, SIM, uji koagulase dan uji gula – gula . Hasil penelitian menunjukkan 23 sampel (tiga belas dari babi pra sapih dan sepuluh dari babi pasca sapih) telah terdeteksi positif Streptococcus sp. ? hemolitik (20 isolat) dan Streptococcus sp. ? hemolitik (3 isolat).

Prevalence, Resistance Profile & Virulence Genes of Streptococcus agalactiae Colonizing Near-term Pregnant Women Attending Ain Shams University Hospital

Group B streptococcus (GBS) is a common cause of infections in pregnant females and non-pregnant adults with chronic diseases (such as diabetes and cancer), also it is the main reason of septicaemia and meningitis in infants. The aim of this study was to figure out how common GBS is in pregnant women, the antimicrobial sensitivity pattern of the isolated GBS colonies and check the presence of scpB and rib virulence genes in these isolates. We screened 203 pregnant women attending the Maternity Hospital of Ain Shams University using vaginal sampling. Isolation was done on CHROMagarTM Strep B & sheep blood agar plates then identified via colony characters, Gram stain, test for catalase production, Christie–Atkins–Munch-Petersen (CAMP) test, test for hippurate hydrolysis and latex agglutination test. This was followed by an antibiotic susceptibility test. Finally, Detection of scpB and rib virulence genes by conventional PCR was done. Our study detected that the prevalence rate of GBS in involved pregnant women was 11.33%. A statistically significant association between colonization and history of spontaneous abortion and preterm labor was observed. CHROMagar™ StrepB showed the same sensitivity of sheep blood agar with extensive effort to isolate suspected GBS colonies from blood agar. GBS was 100% sensitive to levofloxacin, linezolid, cefepime, ceftaroline and ceftriaxone. Also, it was highly sensitive to vancomycin (91.3%). Sensitivity to clindamycin, azithromycin, penicillin and ampicillin was (21.70%, 21.70%,47.80%, 47.80%) respectively. The least sensitivity of GBS was to erythromycin ( 8.7%). All isolates possessed the scpB gene (100%) while only 18 isolates (78.26%) had the rib gene.

Anaerobic infections in patients admitted in various surgical units of a tertiary care hospital of north India: neglected but important

Background and Objectives: Anaerobic infections are usually caused by the host’s endogenous flora due to a breach in the anatomical barriers and Bacteroides spp. are the most notorious organisms associated with anaerobic infections. The identification of anaerobes has been a challenge since times. MALDI-TOF-MS is a boon for aiding the rapid detection of anaerobic organisms and has helped us to enlist the distribution of various anaerobic pathogens. Materials and Methods: This retrospective analysis (January 2018 to December 2019) was carried out in a tertiary care hospital in North India, in which the anaerobic microbiological profile of all patients admitted to surgical wards, ICU, and OPD of various departments (Orthopedics, Surgery, Gynecology, and Obstetrics) was reviewed. Samples received were immediately processed aerobically (5% sheep blood agar and Mac Conkeyagar) as well as anaerobically (RCM and freshly prepared sheep blood agar) as per the laboratory protocols. Results: Bacteroides fragilis (19.12%) was the most common anaerobe whereas among aerobes Escherichia coli (30.2%) followed by Klebsiella pneumoniae (10.34%) were most commonly isolated. The majority of patients were males (56%) and the most common presentation was with abscesses (21.4%). Polymicrobial infections (69.51%) outnumbered monomicrobial ones (30.48%). Conclusion: There is a paucity of literature on anaerobe isolation from surgical infections from our country which motivated us to study anaerobic infections and the high sample size in our institute enabled us to study surgical infections from an anaerobic perspective. This will add to the knowledge of microbiologists and clinicians. MALDI-TOF MS helped in rapid and accurate identification and hence we could report a wider spectrum of organisms in our study

Validation of a Gradient Diffusion Method (Etest®) for Antimicrobial Susceptibility Testing of Aerococcus urinae to Fluoroquinolones

Aerococcus urinae is a urinary pathogen with well-described resistance to fluoroquinolones. This study aimed to validate the gradient diffusion (GD) method (Etest®) on cation-adjusted Mueller-Hinton agar with 5% sheep blood for Aerococcus urinae antimicrobial susceptibility testing (AST) to ciprofloxacin and levofloxacin and compare it to the broth microdilution (BMD) method from CLSI M45-A3. Agar dilution (AD), as recommended by EUCAST, was used as an alternate reference method to arbitrate discrepancies or address technical issues. Aerococcus urinae isolates from urinary specimens were prospectively collected between June 2016 and December 2017 from six Quebec hospitals (Canada) and identifications were confirmed using Vitek MS® with IVD 3.0 database. Of the 207 isolates tested using BMD, 37 (17.9%) showed trailing and 19 (9.2%) showed insufficient growth and were tested using AD. Also, 38 isolates (18.4%) for ciprofloxacin and 13 isolates (6.3%) for levofloxacin showed a lack of essential or categorical agreement between Etest® and BMD and were also tested by AD. Using a combined reference method (BMD or AD), susceptibility rate of Aerococcus urinae was 82.6% and 81.6% for ciprofloxacin and levofloxacin, respectively. Categorial agreement between GD and the combined reference methods was 95.2% for ciprofloxacin and 97.1% for levofloxacin, with no very major error identified. Major and minor error rates were 0.6% and 4.3% for ciprofloxacin, and 1.2% and 1.9% for levofloxacin, respectively. Overall, AST using Etest® on sheep blood agar showed a good agreement with reference methods and can be considered by clinical laboratories wishing to perform AST on Aerococcus urinae isolates.

The type of blood used to feed Aedes aegypti females affects their cuticular and internal free fatty acid (FFA) profiles

Aedes aegypti, the primary vector of various arthropod-borne viral (arboviral) diseases such as dengue and Zika, is a popular laboratory model in vector biology. However, its maintenance in laboratory conditions is difficult, mostly because the females require blood meals to complete oogenesis, which is often provided as sheep blood. The outermost layer of the mosquito cuticle is consists of lipids which protects against numerous entomopathogens, prevents desiccation and plays an essential role in signalling processes. The aim of this work was to determine how the replacement of human blood with sheep blood affects the cuticular and internal FFA profiles of mosquitoes reared in laboratory culture. The individual FFAs present in cuticular and internal extracts from mosquito were identified and quantified by GC–MS method. The normality of their distribution was checked using the Kolmogorov-Smirnov test and the Student’s t-test was used to compare them. GC-MS analysis revealed similar numbers of internal and cuticular FFAs in the female mosquitoes fed sheep blood by membrane (MFSB) and naturally fed human blood (NFHB), however MFSB group demonstrated 3.1 times greater FFA concentrations in the cuticular fraction and 1.4 times the internal fraction than the NFHB group. In the MFSB group, FFA concentration was 1.6 times higher in the cuticular than the internal fraction, while for NFHB, FFA concentration was 1.3 times lower in the cuticular than the internal fraction. The concentration of C18:3 acid was 223 times higher in the internal fraction than the cuticle in the MHSB group but was absent in the NFHB group. MFSB mosquito demonstrate different FFA profiles to wild mosquitoes, which might influence their fertility and the results of vital processes studied under laboratory conditions. The membrane method of feeding mosquitoes is popular, but our research indicates significant differences in the FFA profiles of MFSB and NFHB. Such changes in FFA profile might influence female fertility, as well as other vital processes studied in laboratory conditions, such as the response to pesticides. Our work indicates that sheep blood has potential shortcomings as a substitute feed for human blood, as its use in laboratory studies may yield different results to those demonstrated by free-living mosquitoes.

Epizootic Situation on Anaplasmosis of Small Ruminants in the Irkutsk Region

Anaplasmosis of ruminants is a group of natural focal infections caused by bacteria from the genus Anaplasma of the Anaplasmataceae family. The main etiological agent of anaplasmosis in sheep, goats, and wild ruminants is Anaplasma ovis, which parasitizes in the erythrocytes of these animals. The purpose of this study was the finding and identification of Anaplasma spp. in the blood of small ruminants using genetic methods and obtaining data on the distribution of anaplasmosis in the Irkutsk region. 20 goat blood samples, 611 sheep blood samples and 209 Dermacentor nuttalli ticks from 12 districts of the Irkutsk region were examined for the presence of Anaplasma spp. Only one type of anaplasma, A. ovis, was found among the genotyped samples. A. ovis was found in the blood of sheep and goats in all of the studied districts of the Irkutsk region. The proportion of sheep blood samples containing anaplasma DNA varied from 30 % to 85 %, in goats – from 10 % to 100 % in different districts, and averaged 57.8 % in sheep and 55,0 % in goats. Frequency of infection of D. nuttalli ticks with A. ovis was 5.7 %. The nucleotide sequences of the samples detected in the blood of small ruminants on the territory of the Irkutsk region differed from each other by a single nucleotide substitution and were identical to the sequences of the type strain Haibei, as well as the sequences of A. ovis previously found in the blood of sheep from Mongolia, deer from China, and Dermacentor niveus and Dermacentor nuttalli ticks from China. These sequences were also identical to the sequences previously found in the blood of sheep from Altai and in Dermacentor nuttalli ticks from Tuva, which indicates the wide distribution of these A. ovis genovariants in Siberia and the probable role of D. nuttalli as a carrier of the agent of anaplasmosis of small ruminants in the Irkutsk region.

MALDI-TOF MS Biomarker Detection Models to Distinguish RTX Toxin Phenotypes of Moraxella bovoculi Strains Are Enhanced Using Calcium Chloride Supplemented Agar

Moraxella bovoculi is the bacterium most often cultured from ocular lesions of cattle with infectious bovine keratoconjunctivitis, also known as bovine pinkeye. Some strains of M. bovoculi contain operons encoding for a repeats-in-toxin (RTX) toxin, which is a known virulence factor of multiple veterinary pathogens. We explored the utility of MALDI-TOF MS and biomarker detection models to classify the presence or absence of an RTX phenotype in M. bovoculi. Ninety strains that had undergone whole genome sequencing were classified by the presence or absence of complete RTX operons and confirmed with a visual assessment of hemolysis on blood agar. Strains were grown on Tryptic Soy Agar (TSA) with 5% sheep blood, TSA with 5% bovine blood that was supplemented with 10% fetal bovine serum, 10 mmol/LCaCl2, or both. The formulations were designed to determine the influence of growth media on toxin production or activity, as calcium ions are required for toxin secretion and activity. Mass spectra were obtained for strains grown on each agar formulation and biomarker models were developed using ClinProTools 3.0 software. The most accurate model was developed using spectra from strains grown on TSA with 5% bovine blood and supplemented with CaCl2, which had a sensitivity and specificity of 93.3% and 73.3%, respectively, regarding RTX phenotype classification. The same biomarker model algorithm developed from strains grown on TSA with 5% sheep blood had a substantially lower sensitivity and specificity of 68.0% and 52.0%, respectively. Our results indicate that MALDI-TOF MS biomarker models can accurately classify strains of M. bovoculi regarding the presence or absence of RTX toxin operons and that agar media modifications improve the accuracy of these models.