A bird’s-eye view of chronic unilateral conjunctivitis : remember about Chlamydia psittaci

Chlamydia psittaci causes psittacosis in humans, mainly in people in contact with birds in either the setting of occupational or companion bird exposure. Infection is associated with a range of clinical manifestations from asymptomatic infection to severe atypical pneumonia and systemic disease. C. psittaci has also been associated with ocular adnexal lymphoma in human patients. The current paper describes successful doxycycline treatment of a male patient suffering from C. psittaci chronic unilateral conjunctivitis, most probably linked to the visit of a South African wildlife reserve. Increased awareness among general and occupational physicians, ophthalmologists, clinicians, and the public on the potential of C. psittaci to cause ocular infection is needed

Combined oropharyngeal/nasal swab is equivalent to nasopharyngeal sampling for SARS-CoV-2 diagnostic PCR

BackgroundEarly 2020, a COVID-19 epidemic became a public health emergency of international concern. To address this pandemic broad testing with an easy, comfortable and reliable testing method is of utmost concern. Nasopharyngeal (NP) swab sampling is the reference method though hampered by international supply shortages. A new oropharyngeal/nasal (OP/N) sampling method was investigated using the more readily available throat swab.Results35 patients were diagnosed with SARS-CoV-2 by means of either NP or OP/N sampling. The paired swabs were both positive in 31 patients. The one patient who tested negative on both NP and OP/N swab on admission, was ultimately diagnosed on bronchoalveolar lavage fluid. A strong correlation was found between the viral RNA loads of the paired swabs (r=0.76; P<0.05). The sensitivity of NP and OP/N analysis in hospitalized patients (n=28) was 89.3% and 92.7% respectively.ConclusionsThis study demonstrates equivalence of NP and OP/N sampling for detection of SARS-CoV-2 by means of rRT-PCR. Sensitivity of both NP and OP/N sampling is very high in hospitalized patients

Emergence of methicillin resistance predates the clinical use of antibiotics

The discovery of antibiotics more than 80 years ago has led to considerable improvements in human and animal health. Although antibiotic resistance in environmental bacteria is ancient, resistance in human pathogens is thought to be a modern phenomenon that is driven by the clinical use of antibiotics(1). Here we show that particular lineages of methicillin-resistant Staphylococcus aureus-a notorious human pathogen-appeared in European hedgehogs in the pre-antibiotic era. Subsequently, these lineages spread within the local hedgehog populations and between hedgehogs and secondary hosts, including livestock and humans. We also demonstrate that the hedgehog dermatophyte Trichophyton erinacei produces two beta-lactam antibiotics that provide a natural selective environment in which methicillin-resistant S. aureus isolates have an advantage over susceptible isolates. Together, these results suggest that methicillin resistance emerged in the pre-antibiotic era as a co-evolutionary adaptation of S. aureus to the colonization of dermatophyte-infected hedgehogs. The evolution of clinically relevant antibiotic-resistance genes in wild animals and the connectivity of natural, agricultural and human ecosystems demonstrate that the use of a One Health approach is critical for our understanding and management of antibiotic resistance, which is one of the biggest threats to global health, food security and development

Emergence of methicillin resistance predates the clinical use of antibiotics.

The discovery of antibiotics more than 80 years ago has led to considerable improvements in human and animal health. Although antibiotic resistance in environmental bacteria is ancient, resistance in human pathogens is thought to be a modern phenomenon that is driven by the clinical use of antibiotics1. Here we show that particular lineages of methicillin-resistant Staphylococcus aureus-a notorious human pathogen-appeared in European hedgehogs in the pre-antibiotic era. Subsequently, these lineages spread within the local hedgehog populations and between hedgehogs and secondary hosts, including livestock and humans. We also demonstrate that the hedgehog dermatophyte Trichophyton erinacei produces two β-lactam antibiotics that provide a natural selective environment in which methicillin-resistant S. aureus isolates have an advantage over susceptible isolates. Together, these results suggest that methicillin resistance emerged in the pre-antibiotic era as a co-evolutionary adaptation of S. aureus to the colonization of dermatophyte-infected hedgehogs. The evolution of clinically relevant antibiotic-resistance genes in wild animals and the connectivity of natural, agricultural and human ecosystems demonstrate that the use of a One Health approach is critical for our understanding and management of antibiotic resistance, which is one of the biggest threats to global health, food security and development

Molecular Epidemiology of Livestock-associated Staphylococcus aureus in Animal and Human Populations in Belgium.

Staphylococcus aureus is a major opportunistic pathogen causing a wide range of infections in humans and animals. Methicillin-resistant S. aureus (MRSA) has traditionally been regarded as a strictly human problem, initially confined to the healthcare settings and later a matter of concern in the general community too. All this changed in 2005 with the isolation of a specific MRSA clone, assigned to Clonal Complex (CC)398, from pigs and pig farmers in the Netherlands. These findings triggered worldwide investigation, showing the presence of this livestock-associated (LA)-MRSA clone in a variety of farm animals and in persons in contact with affected animals. Furthermore, the capacity of LA-MRSA CC398 to cause infections in humans and animals has been well documented. Recently, MRSA with a divergent mecA-homologue gene variant has been discovered in bovines and humans. Together, these emerging MRSA strains from animal sources have raised new questions as to their origin and inter-host transmission, as well as raised global concern in both veterinary and human medicine about health risks posed by MRSA prevailing in livestock.<p>In the present work, we aimed to investigate the extent and molecular epidemiology of the LA-MRSA reservoir in animal and human populations, including on livestock farms and in acute-care hospitals in Belgium. As a secondary objective, the presence of methicillin susceptible S. aureus (MSSA) CC398, from which MRSA CC398 could locally emerge by acquisition of the Staphylococal Cassette Chromosome mec (SCCmec) element, was assessed. To this end, we undertook an extensive and systematic cross-sectional survey of S.aureus and MRSA carriage among humans and animals on pig, veal calf, dairy cattle, beef cattle, broiler and horticulture farms. A questionnaire, completed by all farm residents, was used to assess occupational risk factors for human MRSA CC398 carriage. Bacterial genetic characterisation was done by spa typing, SCCmec typing and multi-locus sequence typing (MLST). Antimicrobial susceptibility profiles were determined; the presence of resistance genes and toxin genes were determined by PCR. A second set of S. aureus clinical isolates from two national surveys organised in 2005 and 2008 were characterised using the same methods.<p>Carriage of MRSA CC398 was highly prevalent in animals and humans on pig and veal calf farms and to a significantly lesser extent on beef, dairy, broiler and horticulture farms (Chapter 5.1). Persons who work with pigs or veal calves on a daily basis are at significantly higher risk for MRSA CC398 carriage compared to farm-exposed persons who work with them less regularly or never. In accordance with the results from the present work as well as those from others, it appears important to assess the impact of interventions at farm-level that aim to reduce the MRSA carriage rate in animals, as this would also reduce the risk for MRSA carriage in farmers and relatives.<p> MRSA CC398 isolates, especially those from veal calf farms, were frequently multi-resistant and thereby represent a reservoir of antimicrobial resistance determinants that could be transferred to other, more human-adapted staphylococci or other micro-organisms (Chapter 5.1). Additionally, this multi-resistance phenotype should be considered when applying empiric treatment of human staphylococcal infections in livestock-exposed persons. Only very few major “human-associated” virulence factors were detected, indicating a limited virulence capacity of LA-MRSA CC398 isolates. MRSA strains with the mecA homologue mecC, which is difficult to detect using conventional diagnostic methods, were found in beef and dairy cattle, but not in humans. <p>MSSA CC398 strains from which MRSA CC398 might locally emerge were frequently detected in humans and animals on pig, veal and broiler farms, all of which are commonly known to be affected by MRSA CC398 (Chapter 5.2). Three porcine MSSA CC398-t011 isolates harbored remnant DNA of a composite SCCmec V(5C2&5)c element, from which the mec gene complex was lacking. These findings indicate that the strains were previously involved in SCCmec recombination events. Processes similar to the one described here likely contribute to the enormous diversity of SCCmec elements observed in staphylococci. <p>Although LA-MRSA CC398 strains were frequently detected in livestock and livestock-exposed persons, they only represented a minority (~1%) of the MRSA strains from hospitalised patients. This suggests that this specific MRSA clone has not yet spread among Belgian patients without livestock contact (Chapter 5.3). However, similar to what has been seen in other countries, we observed a recent emergence of severe infections, caused by a human-adapted subclone of MSSA CC398, in hospitalised patients without livestock contact (Chapter 5.4). <p>Once more has S. aureus proven its versatility: it has optimally adapted to the selective pressure exerted by intensive animal farming by acquisition of mobile genetic elements, such as resistance determinants. Clearly MRSA is no longer a strictly human problem. Working across the human and veterinary health sectors will be essential to tackle the dissemination and pathogenic evolution of MRSA in livestock. <p>Doctorat en Sciences biomédicales et pharmaceutiquesinfo:eu-repo/semantics/nonPublishe

Impact of the introduction of EUCAST’s concept of “area of technical uncertainty”

On the first of January 2019, the European Committee on Antimicrobial Susceptibility Testing, EUCAST, introduced the concept of "area of technical uncertainty" (ATU). The aim was to report on the incidence of ATU test results in a selection of common bacterial species and the subsequent impact on antimicrobial resistance categorization and workload. A retrospective analysis of clinical samples collected from February 2019 until November 2019 was performed. Susceptibility to amoxicillin-clavulanic acid and piperacillin-tazobactam in Enterobacterales (Escherichia spp., Klebsiella spp., Proteus spp.), piperacillin-tazobactam in Pseudomonas aeruginosa, and amoxicillin-clavulanic acid and cefuroxime in Haemophilus influenzae was studied. Disk diffusion antibiotic susceptibility testing was read and interpreted by ADAGIO 93400 automated system (Bio-Rad, France). In case of an inhibition zone in the ATU, strains were retested using gradient minimal inhibitory concentration method (Etest, BioMerieux, France). Overall, 14,164 isolate-antibiotic combinations were tested in 7922 isolates, resulting in 1204 (8.5%) disk zone diameters in the ATU region. Retesting of ATUs with Etest resulted in a category change from S to R for amoxicillin-clavulanic acid in 63/498 (12.7%) of Escherichia spp., 2/58 (3.4%) of Klebsiella spp., 2/37 (5.4%) of Proteus spp., and 6/125 (4.8%) of Haemophilus influenzae. For piperacillin-tazobactam, a category change from S to R was found in 33/92 (35.9%) of Pseudomonas aeruginosa. We conclude that ATU testing has a substantial impact on the correct interpretation of antimicrobial resistance, at the expense of turn-around time and with the cost of additional workload

Evaluation of the Seegene Allplex? Respiratory Panel for diagnosis of acute respiratory tract infections

Objectives: The Seegene AllplexTM Respiratory panel was retrospectively challenged using a collection of quality control samples (QCMD) and clinical samples previously analysed with validated routine methods. Methods: A collection of 111 samples [43 QCMD samples, 13 bronchoalveolar lavage fluids and 55 nasopharyngeal aspirates/swabs] was tested with Seegene AllplexTM. The clinical samples were tested previously using either FTD® Respiratory Pathogens 21 qPCR assay (Fast Track Diagnostics), an in-house multiplex PCR for Bordetella, or BioGX Sample-ReadyTM Atypical pneumo panel (Becton Dickinson). Samples were stored at -80°C prior to analysis with Seegene Allplex™, nucleic acids were automatically extracted with NucliSENS Easymag (bioMérieux). Samples returning discordant results were subjected to repeat testing and/or additional testing by reference laboratories. Results: Seegene correctly identified 41/43 QCMD samples (95.4%); two samples positive for respiratory syncytial virus (RSV) and human metapneumovirus, respectively, were only correctly identified following repeat testing. In the 56 clinical samples, overall, 97 pathogens were identified: 65 pathogens (67.0%) were detected both by routine methods and Seegene, 24 pathogens (24.7%) only by routine methods, and 8 pathogens (8.2%) only by Seegene. The majority of discordant results was detected in samples with low pathogen load (22/32, 68.8%) and in samples containing multiple pathogens (25/32, 78.1%). Full agreement between methods was observed for influenza, RSV, adenovirus, Bordetella (para)pertussis and Chlamydiapneumoniae. Discordance was observed for human metapneumovirus, coronavirus OC43, bocavirus and parainfluenza virus, mainly type 4. Conclusion: Overall, the Seegene AllplexTM assay performed well for routine detection of important respiratory targets. Acceptable agreement was observed between Seegene and other routine assays.status: publishe