89 research outputs found
Prevalence, antimicrobial resistance and genetic diversity of Campylobacter coli and Campylobacter jejuni in Ecuadorian broilers at slaughter age
Thermotolerant Campylobacter spp. are a major cause of foodborne gastrointestinal infections worldwide. The linkage of human campylobacteriosis and poultry has been widely described. In this study we aimed to investigate the prevalence, antimicrobial resistance and genetic diversity of C. coli and C. jejuni in broilers from Ecuador. Caecal content from 379 randomly selected broiler batches originating from 115 farms were collected from 6 slaughterhouses located in the province of Pichincha during 1 year. Microbiological isolation was performed by direct plating on mCCDA agar. Identification of Campylobacter species was done by PCR. Minimum inhibitory concentration (MIC) values for gentamicin, ciprofloxacin, nalidixic acid, tetracycline, streptomycin, and erythromycin were obtained. Genetic variation was assessed by RFLP-flaA typing and Multilocus Sequence Typing (MLST) of selected isolates. Prevalence at batch level was 64.1%. Of the positive batches 68.7% were positive for C. coli, 18.9% for C. jejuni, and 12.4% for C. coli and C. jejuni. Resistance rates above 67% were shown for tetracycline, ciprofloxacin, and nalidixic acid. The resistance pattern tetracycline, ciprofloxin, and nalidixic acid was the dominant one in both Campylobacter species. RFLP-flaA typing analysis showed that C. coli and C. jejuni strains belonged to 38 and 26 profiles respectively. On the other hand MLST typing revealed that C. coli except one strain belonged to CC-828, while C. jejuni except 2 strains belonged to 12 assigned clonal complexes (CCs). Furthermore 4 new sequence types (STs) for both species were described, whereby 2 new STs for C. coli were based on new allele sequences. Further research is necessary to estimate the impact of the slaughter of Campylobacter positive broiler batches on the contamination level of carcasses in slaughterhouses and at retail in Ecuador
Investigation of MALDI-TOF Mass Spectrometry for Assessing the Molecular Diversity of Campylobacter jejuni and Comparison with MLST and cgMLST: A Luxembourg One-Health Study
There is a need for active molecular surveillance of human and veterinary Campylobacter
infections. However, sequencing of all isolates is associated with high costs and a considerable
workload. Thus, there is a need for a straightforward complementary tool to prioritize isolates to
sequence. In this study, we proposed to investigate the ability of MALDI-TOF MS to pre-screen C.
jejuni genetic diversity in comparison to MLST and cgMLST. A panel of 126 isolates, with 10 clonal
complexes (CC), 21 sequence types (ST) and 42 different complex types (CT) determined by the
SeqSphere+ cgMLST, were analysed by a MALDI Biotyper, resulting into one average spectra per
isolate. Concordance and discriminating ability were evaluated based on protein profiles and different
cut-offs. A random forest algorithm was trained to predict STs. With a 94% similarity cut-off, an
AWC of 1.000, 0.933 and 0.851 was obtained for MLSTCC, MLSTST and cgMLST profile, respectively.
The random forest classifier showed a sensitivity and specificity up to 97.5% to predict four different
STs. Protein profiles allowed to predict C. jejuni CCs, STs and CTs at 100%, 93% and 85%, respectively.
Machine learning and MALDI-TOF MS could be a fast and inexpensive complementary tool to give
an early signal of recurrent C. jejuni on a routine basis
Combination of MALDI-TOF Mass Spectrometry and Machine Learning for Rapid Antimicrobial Resistance Screening: The Case of Campylobacter spp.
While MALDI-TOF mass spectrometry (MS) is widely considered as the reference
method for the rapid and inexpensive identification of microorganisms in routine
laboratories, less attention has been addressed to its ability for detection of antimicrobial
resistance (AMR). Recently, some studies assessed its potential application together
with machine learning for the detection of AMR in clinical pathogens. The scope of
this study was to investigate MALDI-TOF MS protein mass spectra combined with
a prediction approach as an AMR screening tool for relevant foodborne pathogens,
such as Campylobacter coli and Campylobacter jejuni. A One-Health panel of 224
C. jejuni and 116 C. coli strains was phenotypically tested for seven antimicrobial
resistances, i.e., ciprofloxacin, erythromycin, tetracycline, gentamycin, kanamycin,
streptomycin, and ampicillin, independently, and were submitted, after an on- and
off-plate protein extraction, to MALDI Biotyper analysis, which yielded one average
spectra per isolate and type of extraction. Overall, high performance was observed
for classifiers detecting susceptible as well as ciprofloxacin- and tetracycline-resistant
isolates. A maximum sensitivity and a precision of 92.3 and 81.2%, respectively, were
reached. No significant prediction performance differences were observed between on and off-plate types of protein extractions. Finally, three putative AMR biomarkers for
fluoroquinolones, tetracyclines, and aminoglycosides were identified during the current
study. Combination of MALDI-TOF MS and machine learning could be an efficient and
inexpensive tool to swiftly screen certain AMR in foodborne pathogens, which may
enable a rapid initiation of a precise, targeted antibiotic treatment
Development and Potential Usefulness of the COVID-19 Ag Respi-Strip Diagnostic Assay in a Pandemic Context
Introduction: COVID-19 Ag Respi-Strip, an immunochromatographic (ICT) assay for
the rapid detection of SARS-CoV-2 antigen on nasopharyngeal specimen, has been
developed to identify positive COVID-19 patients allowing prompt clinical and quarantine
decisions. In this original research article, we describe the conception, the analytical and
clinical performances as well as the risk management of implementing the COVID-19 Ag
Respi-Strip in a diagnostic decision algorithm.
Materials and Methods: Development of the COVID-19 Ag Respi-Strip resulted
in a ready-to-use ICT assay based on a membrane technology with colloidal gold
nanoparticles using monoclonal antibodies directed against the SARS-CoV and
SARS-CoV-2 highly conserved nucleoprotein antigen. Four hundred observations were
recorded for the analytical performance study and thirty tests were analyzed for the crossreactivity
study. The clinical performance study was performed in a retrospective multicentric
evaluation on aliquots of 328 nasopharyngeal samples. COVID-19 Ag Respi-Strip
results were compared with qRT-PCR as golden standard for COVID-19 diagnostics.
Results: In the analytical performance study, the reproducibility showed a
between-observer disagreement of 1.7%, a robustness of 98%, an overall satisfying user
friendliness and no cross-reactivity with other virus-infected nasopharyngeal samples. In
the clinical performance study performed in three different clinical laboratories during
the ascendant phase of the epidemiological curve, we found an overall sensitivity and
specificity of 57.6 and 99.5%, respectively with an accuracy of 82.6%. The cut-off
of the ICT was found at CT < 22. User-friendliness analysis and risk management
assessment through Ishikawa diagram demonstrate that COVID-19 Ag Respi-Strip may
be implemented in clinical laboratories according to biosafety recommendations.
Conclusion: The COVID-19 Ag Respi-Strip represents a promising rapid SARS-CoV-2
antigen assay for the first-line diagnosis of COVID-19 in 15min at the peak of the
pandemic. Its role in the proposed diagnostic algorithm is complementary to the
currently-used molecular techniques
Haemophilus influenzae carriage and antibiotic resistance profile in Belgian infants over a three-year period (2016–2018)
BackgroundNon-typeable Haemophilus influenzae has become increasingly important as a causative agent of invasive diseases following vaccination against H. influenzae type b. The emergence of antibiotic resistance underscores the necessity to investigate typeable non-b carriage and non-typeable H. influenzae (NTHi) in children.MethodsNasopharyngeal swab samples were taken over a three-year period (2016–2018) from 336 children (6–30 months of age) attending daycare centers (DCCs) in Belgium, and from 218 children with acute otitis media (AOM). Biotype, serotype, and antibiotic resistance of H. influenzae strains were determined phenotypically. Mutations in the ftsI gene were explored in 129 strains that were resistant or had reduced susceptibility to beta-lactam antibiotics. Results were compared with data obtained during overlapping time periods from 94 children experiencing invasive disease.ResultsOverall, NTHi was most frequently present in both carriage (DCC, AOM) and invasive group. This was followed by serotype “f” (2.2%) and “e” (1.4%) in carriage, and “b” (16.0%), “f” (11.7%), and “a” (4.3%) in invasive strains. Biotype II was most prevalent in all studied groups, followed by biotype III in carriage and I in invasive strains. Strains from both groups showed highest resistance to ampicillin (26.7% in carriage vs. 18.1% in invasive group). A higher frequency of ftsI mutations were found in the AOM group than the DCC group (21.6 vs. 14.9% – p = 0.056). Even more so, the proportion of biotype III strains that carried a ftsI mutation was higher in AOM compared to DCC (50.0 vs. 26.3% – p < 0.01) and invasive group.ConclusionIn both groups, NTHi was most frequently circulating, while specific encapsulated serotypes for carriage and invasive group were found. Biotypes I, II and III were more frequently present in the carriage and invasive group. The carriage group had a higher resistance-frequency to the analyzed antibiotics than the invasive group. Interestingly, a higher degree of ftsI mutations was found in children with AOM compared to DCC and invasive group. This data helps understanding the H. influenzae carriage in Belgian children, as such information is scarce
Trends in invasive bacterial diseases during the first 2 years of the COVID-19 pandemic: analyses of prospective surveillance data from 30 countries and territories in the IRIS Consortium.
BACKGROUND
The Invasive Respiratory Infection Surveillance (IRIS) Consortium was established to assess the impact of the COVID-19 pandemic on invasive diseases caused by Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Streptococcus agalactiae. We aimed to analyse the incidence and distribution of these diseases during the first 2 years of the COVID-19 pandemic compared to the 2 years preceding the pandemic.
METHODS
For this prospective analysis, laboratories in 30 countries and territories representing five continents submitted surveillance data from Jan 1, 2018, to Jan 2, 2022, to private projects within databases in PubMLST. The impact of COVID-19 containment measures on the overall number of cases was analysed, and changes in disease distributions by patient age and serotype or group were examined. Interrupted time-series analyses were done to quantify the impact of pandemic response measures and their relaxation on disease rates, and autoregressive integrated moving average models were used to estimate effect sizes and forecast counterfactual trends by hemisphere.
FINDINGS
Overall, 116 841 cases were analysed: 76 481 in 2018-19, before the pandemic, and 40 360 in 2020-21, during the pandemic. During the pandemic there was a significant reduction in the risk of disease caused by S pneumoniae (risk ratio 0·47; 95% CI 0·40-0·55), H influenzae (0·51; 0·40-0·66) and N meningitidis (0·26; 0·21-0·31), while no significant changes were observed for S agalactiae (1·02; 0·75-1·40), which is not transmitted via the respiratory route. No major changes in the distribution of cases were observed when stratified by patient age or serotype or group. An estimated 36 289 (95% prediction interval 17 145-55 434) cases of invasive bacterial disease were averted during the first 2 years of the pandemic among IRIS-participating countries and territories.
INTERPRETATION
COVID-19 containment measures were associated with a sustained decrease in the incidence of invasive disease caused by S pneumoniae, H influenzae, and N meningitidis during the first 2 years of the pandemic, but cases began to increase in some countries towards the end of 2021 as pandemic restrictions were lifted. These IRIS data provide a better understanding of microbial transmission, will inform vaccine development and implementation, and can contribute to health-care service planning and provision of policies.
FUNDING
Wellcome Trust, NIHR Oxford Biomedical Research Centre, Spanish Ministry of Science and Innovation, Korea Disease Control and Prevention Agency, Torsten Söderberg Foundation, Stockholm County Council, Swedish Research Council, German Federal Ministry of Health, Robert Koch Institute, Pfizer, Merck, and the Greek National Public Health Organization
Gender Gap in Parental Leave Intentions: Evidence from 37 Countries
Despite global commitments and efforts, a gender-based division of paid and unpaid work persists. To identify how psychological factors, national policies, and the broader sociocultural context contribute to this inequality, we assessed parental-leave intentions in young adults (18–30 years old) planning to have children (N = 13,942; 8,880 identified as women; 5,062 identified as men) across 37 countries that varied in parental-leave policies and societal gender equality. In all countries, women intended to take longer leave than men. National parental-leave policies and women’s political representation partially explained cross-national variations in the gender gap. Gender gaps in leave intentions were paradoxically larger in countries with more gender-egalitarian parental-leave policies (i.e., longer leave available to both fathers and mothers). Interestingly, this cross-national variation in the gender gap was driven by cross-national variations in women’s (rather than men’s) leave intentions. Financially generous leave and gender-egalitarian policies (linked to men’s higher uptake in prior research) were not associated with leave intentions in men. Rather, men’s leave intentions were related to their individual gender attitudes. Leave intentions were inversely related to career ambitions. The potential for existing policies to foster gender equality in paid and unpaid work is discussed.Gender Gap in Parental Leave Intentions: Evidence from 37 CountriespublishedVersio
Gender Gap in Parental Leave Intentions: Evidence from 37 Countries
Despite global commitments and efforts, a gender-based division of paid and unpaid work persists. To identify how psychological factors, national policies, and the broader sociocultural context contribute to this inequality, we assessed parental-leave intentions in young adults (18–30 years old) planning to have children (N = 13,942; 8,880 identified as women; 5,062 identified as men) across 37 countries that varied in parental-leave policies and societal gender equality. In all countries, women intended to take longer leave than men. National parental-leave
policies and women’s political representation partially explained cross-national
variations in the gender gap. Gender gaps in leave intentions were paradoxically
larger in countries with more gender-egalitarian parental-leave policies (i.e., longer leave available to both fathers and mothers). Interestingly, this cross-national
variation in the gender gap was driven by cross-national variations in women’s (rather than men’s) leave intentions. Financially generous leave and gender-egalitarian policies (linked to men’s higher uptake in prior research) were not associated with leave intentions in men. Rather, men’s leave intentions were related to their individual gender attitudes. Leave intentions were inversely related to career ambitions. The potential for existing policies to foster gender equality in paid and unpaid work is discussed
A genomic appraisal of invasive Salmonella Typhimurium and associated antibiotic resistance in sub-Saharan Africa
Invasive non-typhoidal Salmonella (iNTS) disease manifesting as bloodstream infection with high mortality is responsible for a huge public health burden in sub-Saharan Africa. Salmonella enterica serovar Typhimurium (S. Typhimurium) is the main cause of iNTS disease in Africa. By analysing whole genome sequence data from 1303 S. Typhimurium isolates originating from 19 African countries and isolated between 1979 and 2017, here we show a thorough scaled appraisal of the population structure of iNTS disease caused by S. Typhimurium across many of Africa’s most impacted countries. At least six invasive S. Typhimurium clades have already emerged, with ST313 lineage 2 or ST313-L2 driving the current pandemic. ST313-L2 likely emerged in the Democratic Republic of Congo around 1980 and further spread in the mid 1990s. We observed plasmid-borne as well as chromosomally encoded fluoroquinolone resistance underlying emergences of extensive-drug and pan-drug resistance. Our work provides an overview of the evolution of invasive S. Typhimurium disease, and can be exploited to target control measures
Contribution de la spectrométrie de masse MALDI-TOF dans le diagnostic microbiologique et la prise en charge clinique du patient infecté
In infected patients, the rapid identification of pathogens is critical. After a long period of slow technological improvement, the microbiology laboratory is now undergoing significant evolution. This work evaluated the contribution of recent MALDI-TOF MS technology in terms of the diagnosis and clinical management of patients and its implementation in the laboratory of tomorrow. The studies were conducted over a 3.5-year period, mostly in the iris public hospital network of Brussels. First, we confirmed the accurate performance of MALDI-TOF MS in the identification of routine isolates, regardless of whether the Biotyper (92.7% correct species identification) or VITEK MS (93.2%) (n=986) commercial system was used, and demonstrated the supremacy of this technology over conventional identification techniques for fastidious bacteria, including Campylobacter and related organisms (98.3%, 72.2% and 79.9% correct species identification by Biotyper, Vitek NH Card and API Campy, respectively; n=234). Second, we showed that the direct MALDI-TOF MS identification of bacteria from positive blood cultures was not only feasible but also led to an 24-h reduction in the time-to-identification. In an adult population, more than 13% of the direct identifications from positive blood cultures resulted in the faster adaptation of the antimicrobial treatment. Third, we demonstrated that MALDI-TOF MS could easily be implemented in a network, which was associated with significant cost savings and reduction in the time-to-identification. Finally, our promising Blastocystis subtyping results suggest that the number of MALDI-TOF MS applications may be increased.In the future, automation of the technique will make its use in clinical laboratories even easier, eliminating the use of conventional identification techniques. Improvement of the preanalytical procedures is also important to make MALDI-TOF MS a suitable instrument for resistance and toxicity mechanism detection and subtyping. Doctorat en Sciences biomédicales et pharmaceutiquesinfo:eu-repo/semantics/nonPublishe
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