Increased incidence of Mycoplasma pneumoniae infections and hospital admissions in the Netherlands, November to December 2023.

Mycoplasma pneumoniae is an important cause of pneumonia and extra-pulmonary manifestations. We observed a rise in admissions due to M. pneumoniae infections starting October 2023 in a regional hospital in the Netherlands and an increased incidence in national surveillance data. The incidence in the Netherlands has not been that high since 2011. The patients had a lower median age compared with 2019 and 2020 (28 vs 40 years). M. pneumoniae should be considered in patients with respiratory symptoms, especially children.

Nasal discharge: A unique enhanced alternative for the detection of respiratory pathogens in adults.

Upper respiratory tract infections are a significant cause of social- and disease burden worldwide. Currently, invasive and uncomfortable molecular detection methods are used for respiratory pathogen detection. We aimed to assess the ability and bearability of a rhinorrhea swab (RS) to detect respiratory pathogens in comparison to the combined nasopharyngeal and oropharyngeal swab (NP/OP). This study was performed at a Public Health Service severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) testing facility between November and December 2022 in the Netherlands. Adults aged 16 years and older, being subjected to a standard of care NP/OP swab with nasal discharge, were included and received an additional RS. Respiratory pathogen detection was evaluated using SARS-CoV-2 polymerase chain reaction (PCR) and multiplex ligation-dependent probe amplification (MLPA) PCR. Bearability was evaluated using visual analog scale (VAS) scores and a questionnaire. A total of 100 adults with a mean age ± SD of 46 ± 16 years were included. The NP/OP swab detected 104 pathogens, the RS 83 pathogens (p < 0.001), and in total 108 respiratory pathogens were identified in 89 adults (89%). The ability to detect respiratory pathogens compared between the RS and the combined NP/OP swab revealed a sensitivity of 82% (95% CI 73%-89%) and specificity of 100% (95% CI 72%-100%). RS were significantly more bearable than the combined NP/OP swab (p value < 0.001). Therefore, nasal discharge found in adults can be used as an adequate reliable medium for respiratory pathogen detection using SARS-CoV-2 PCR and MLPA PCR.

Clinical validation of novel dried blood spot based collecting device using serum separation for measuring SARS-CoV-2 antibodies.

Accurate surveillance of coronavirus disease 2019 (COVID-19) incidence includes large-scale antibody testing of the population. Current testing methods require collection of venous blood samples by a healthcare worker, or dried blood spot (DBS) collection using finger prick, however this might have some logistic and processing limitations. We investigated the performance of the Ser-Col device for detecting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies using a finger prick: DBS-like collection system that includes a lateral flow paper for serum separation and allows for automated large scale analysis. For this prospective study, adult patients with moderate to severe COVID-19 were included 6 weeks post-symptom onset. Healthy, adult volunteers were included as a negative control group. Venous blood and capillary blood using the Ser-Col device were collected and the Wantai SARS-CoV-2 total antibody ELISA was performed on all samples. We included 50 subjects in the study population and 49 in the control group. Results obtained with venous blood versus Ser-Col capillary blood showed 100% sensitivity (95% CI: 0.93-1.00) and 100% specificity (95% CI: 0.93-1.00). Our study shows the feasibility of SARS-CoV-2 total antibody screening using a standardized DBS technique with semiautomated processing for large scale analysis.

Similar Sensitivity of SARS-CoV-2 Detection in Oropharyngeal/Nasopharyngeal and Saliva Samples on the Hologic Panther Platform.

BACKGROUND: Oropharyngeal (OP) and nasopharyngeal (NP) sampling has historically been considered the reference specimen type used for respiratory virus detection. Saliva could be a less invasive alternative for SARS-CoV-2 detection, but limited evidence is available. METHODS: The technical and clinical performance of saliva was compared to OP/NP on the Hologic Panther platform with two Aptima assays, the End-Point Transcription-Mediated Amplification assay (EP-TMA) and Real-Time Transcription-Mediated Amplification assay (RT-TMA). The samples were collected at the Public Health Service Testing Site XL location in Schiphol Amsterdam Airport. At the site, the Regional Public Health Laboratory Kennemerland (RPHLK) has a fully equipped laboratory facility. RESULTS: A total of 374 samples (187 OP/NP swabs and 187 saliva samples) were collected from 187 unique patients. The Real-Time Transcription-Mediated Amplification assay (RT-TMA) resulted in comparable sensitivities for the detection of SARS-CoV-2 in both the OP/NP swabs (88.3%; 113/128) and saliva samples (87.5%; 112/128). The End-Point Transcription-Mediated Amplification assay (EP-TMA) analyses showed a similar sensitivity (86.7%; 111/128) in the OP/NP swabs but a lower sensitivity in the saliva samples (80.5%; 103/128). Within the discordant analyses, we found no associations in the symptoms, earlier SARS-CoV-2 infections and eating, smoking, drinking and tooth brushing habits within one hour before testing. CONCLUSIONS: The Hologic Panther platform Real-Time Transcription-Mediated Amplification assay (RT-TMA) yields a sensitivity for the detection of SARS-CoV-2 in saliva that is comparable to the OP/NP swabs derived from participants presenting themselves at a public health testing facility with minimal or mild symptoms.

High detection rate of viral pathogens in nasal discharge in children aged 0 till 5 years.

Respiratory tract infections (RTI) in children remain a cause of disease burden worldwide. Nasopharyngeal (NP) & oropharyngeal (OP) swabs are used for respiratory pathogen detection, but hold disadvantages particularly for children, highlighting the importance and preference for a child friendly detection method. We aimed to evaluate the performance and tolerability of a rhinorrhea swab (RS) in detecting viral pathogens when compared to a combined OP(/NP) or mid-turbinate (MT) nasal swab. This study was conducted between September 2021 and July 2022 in the Netherlands. Children aged 0-5 years, with an upper RTI and nasal discharge, were included and received a combined swab and a RS. Multiplex polymerase chain reaction (PCR) and severe acute respiratory syndrome coronavirus-2 PCR were used for viral pathogen detection. Tolerability was evaluated with a questionnaire and visual analog scale (VAS) scores. During 11 months 88 children were included, with a median age of 1.00 year [interquartile range 0.00-3.00]. In total 122 viral pathogens were detected in 81 children (92%). Sensitivity and specificity of the RS compared to a combined swab were respectively 97% (95% confidence interval [CI] 91%-100%) and 78% (95% CI 45%-94%). Rhinorrhea samples detected more pathogens than the (combined) nasal samples, 112 versus 108 respectively. Median VAS scores were significantly lower for the RS in both children (2 vs. 6) and their parents (0 vs. 5). A RS can therefore just as effectively/reliably detect viral pathogens as the combined swab in young children and is better tolerated by both children and their parents/caregivers.

Longitudinal Household Assessment of Respiratory Illness in Children and Parents During the COVID-19 Pandemic.

Importance: In the early COVID-19 pandemic, SARS-CoV-2 testing was only accessible and recommended for symptomatic persons or adults. This restriction hampered assessment of the true incidence of SARS-CoV-2 infection in children as well as detailed characterization of the SARS-CoV-2 disease spectrum and how this spectrum compared with that of other common respiratory illnesses. Objective: To estimate the community incidence of SARS-CoV-2 infection in children and parents and to assess the symptoms and symptom severity of respiratory illness episodes involving SARS-CoV-2-positive test results relative to those with SARS-CoV-2-negative test results. Design, Setting, and Participants: This cohort study randomly selected Dutch households with at least 1 child younger than 18 years. A total of 1209 children and adults from 307 households were prospectively followed up between August 25, 2020, and July 29, 2021, covering the second and third waves of the COVID-19 pandemic. Participation included SARS-CoV-2 screening at 4- to 6-week intervals during the first 23 weeks of participation (core study period; August 25, 2020, to July 29, 2021). Participants in all households finishing the core study before July 1, 2021, were invited to participate in the extended follow-up and to actively report respiratory symptoms using an interactive app until July 1, 2021. At new onset of respiratory symptoms or a SARS-CoV-2 positive test result, a household outbreak study was initiated, which included daily symptom recording, repeated polymerase chain reaction testing (nose-throat swabs and saliva and fecal samples), and SARS-CoV-2 antibody measurement (paired dried blood spots) in all household members. Outbreaks, households, and episodes of respiratory illness were described as positive or negative depending on SARS-CoV-2 test results. Data on participant race and ethnicity were not reported because they were not uniformly collected in the original cohorts and were therefore not representative or informative. Exposures: SARS-CoV-2-positive and SARS-CoV-2-negative respiratory illness episodes. Main Outcomes and Measures: Age-stratified incidence rates, symptoms, and symptom severity for SARS-CoV-2-positive and SARS-CoV-2-negative respiratory illness episodes. Results: Among 307 households including 1209 participants (638 female [52.8%]; 403 [33.3%] aged <12 years, 179 [14.8%] aged 12-17 years, and 627 [51.9%] aged ≥18 years), 183 household outbreaks of respiratory illness were observed during the core study and extended follow-up period, of which 63 (34.4%) were SARS-CoV-2 positive (59 outbreaks [32.2%] during the core study and 4 outbreaks [2.2%] during follow-up). SARS-CoV-2 incidence was similar across all ages (0.24/person-year [PY]; 95% CI, 0.21-0.28/PY). Overall, 33 of 134 confirmed SARS-CoV-2 episodes (24.6%) were asymptomatic. The incidence of SARS-CoV-2-negative respiratory illness episodes was highest in children younger than 12 years (0.94/PY; 95% CI, 0.89-0.97/PY). When comparing SARS-CoV-2-positive vs SARS-CoV-2-negative respiratory illness episodes in children younger than 12 years, no differences were observed in number of symptoms (median [IQR], 2 [2-4] for both groups), symptom severity (median [IQR] maximum symptom severity score, 6 [4-9] vs 7 [6-13]), or symptom duration (median [IQR], 6 [5-12] days vs 8 [4-13] days). However, among adults, SARS-CoV-2-positive episodes had a significantly higher number (median [IQR], 6 [4-8] vs 3 [2-4]), severity (median [IQR] maximum symptom severity score, 15 [9-19] vs 7 [6-11]), and duration (median [IQR] 13 [8-29] days vs 5 [3-11] days; P < .001 for all comparisons) of symptoms vs SARS-CoV-2-negative episodes. Conclusions and Relevance: In this cohort study, during the first pandemic year when mostly partial or full in-person learning occurred, the SARS-CoV-2 incidence rate in children was substantially higher than estimated from routine testing or seroprevalence data and was similar to that of adult household members. Unlike in unvaccinated adults, SARS-CoV-2 symptoms and symptom severity in children were similar to other common respiratory illnesses. These findings may prove useful when developing pediatric COVID-19 vaccine recommendations.

High Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Household Transmission Rates Detected by Dense Saliva Sampling.

BACKGROUND: Understanding the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) household transmission is important for adequate infection control measures in this ongoing pandemic. METHODS: Households were enrolled upon a polymerase chain reaction-confirmed index case between October and December 2020, prior to the coronavirus disease 2019 vaccination program. Saliva samples were obtained by self-sampling at days 1, 3, 5, 7, 10, 14, 21, 28, 35, and 42 from study inclusion. Nasopharyngeal swabs (NPS) and oropharyngeal swabs (OPS) were collected by the research team at day 7 and capillary blood samples at day 42. Household secondary attack rate (SAR) and per-person SAR were calculated based on at least 1 positive saliva, NPS, OPS, or serum sample. Whole genome sequencing was performed to investigate the possibility of multiple independent SARS-CoV-2 introductions within a household. RESULTS: Eighty-five households were included consisting of 326 (unvaccinated) individuals. Comparable numbers of secondary cases were identified by saliva (133/241 [55.2%]) and serum (127/213 [59.6%]). The household SAR was 88.2%. The per-person SAR was 64.3%. The majority of the secondary cases tested positive in saliva at day 1 (103/150 [68.7%]). Transmission from index case to household member was not affected by age or the nature of their relationship. Phylogenetic analyses suggested a single introduction for the investigated households. CONCLUSIONS: Households have a pivotal role in SARS-CoV-2 transmission. By repeated saliva self-sampling combined with NPS, OPS, and serology, we found the highest SARS-CoV-2 household transmission rates reported to date. Salivary (self-) sampling of adults and children is suitable and attractive for near real-time monitoring of SARS-CoV-2 transmission in this setting.

The Effect of Varying Interval Definitions on the Prevalence of SARS-CoV-2 Reinfections: A Retrospective Cross-Sectional Cohort Study.

BACKGROUND: We assessed the SARS-CoV-2 reinfection rate in a large patient cohort, and evaluated the effect of varying time intervals between two positive tests on assumed reinfection rates using viral load data. METHODS: All positive SARS-CoV-2 samples collected between 1 March 2020 and 1 August 2021 from a laboratory in the region Kennemerland, the Netherlands, were included. The reinfection rate was analyzed using different time intervals between two positive tests varying between 2 and 16 weeks. SARS-CoV-2 PCR crossing point (Cp) values were used to estimate viral loads. RESULTS: In total, 679,513 samples were analyzed, of which 53,366 tests (7.9%) were SARS-CoV-2 positive. The number of reinfections varied between 260 (0.52%) for an interval of 2 weeks, 89 (0.19%) for 4 weeks, 52 (0.11%) for 8 weeks, and 37 (0.09%) for a minimum interval of 16 weeks between positive tests. The median Cp-value (IQR) in the second positive samples decreased when a longer interval was chosen, but stabilized from week 8 onwards. CONCLUSIONS: Although the calculated reinfection prevalence was relatively low (0.11% for the 8-week time interval), choosing a different minimum interval between two positive tests resulted in major differences in reinfection rates. As reinfection Cp-values stabilized after 8 weeks, we hypothesize this interval to best reflect novel infection rather than persistent shedding.

Respiratory Pathogen Detection in Children: Saliva as a Diagnostic Specimen.

We compared pathogen detection between saliva, nasopharyngeal and oropharyngeal swabs in children with respiratory symptoms. The sensitivity in nasopharyngeal swabs was 93% (95% confidence interval [CI]: 78%-98%), in oropharyngeal swabs 79% (95% CI: 60%-90%), in saliva overall 76% (95% CI: 58%-88%) and in 18 saliva samples collected with drooling or sponges, 94% (95% CI: 74%-99%). Saliva could be a relevant specimen alternative.

Performance- and cost-benefit analysis of an influenza point-of-care test compared to laboratory-based multiplex RT-PCR in the emergency department.

INTRODUCTION: Influenza poses a heavy burden on emergency departments (ED) and hospital wards. Fast and reliable bedside tests are invaluable in obtaining indications for (cohort) droplet isolation precautions and improving patient flow. We performed a cost-benefit analysis comparing influenza point-of-care testing (POCT) to laboratory-based multiplex ligation-dependent probe amplification. METHODS: Data of 275 ED presentations between January-April 2019 were analyzed. Patients received both POCT and MLPA to calculate POCT sensitivity and specificity. Costs were calculated for both a POCT and MLPA scenario, including costs for testing, admission, droplet isolation precautions and cleaning. RESULTS: In our study population, 34 patients (12%) were identified with influenza A. No cases of influenza B were identified. Mean age of the influenza positive patients was 75(18) years and 56% were male. The most common symptoms upon presentation were cough, malaise and fever, with 74%, 56% and 50%, respectively. Compared to MLPA, POCT yielded a sensitivity of 94%, a specificity of 98% and a negative predictive value of 99% for influenza A. Using POCT yielded a cost reduction of €93,26 per patient. CONCLUSIONS: Influenza POCT is an accurate and cost-beneficial method to differentiate between admission with or without droplet isolation precautions. It can be useful in clinical decision making and reducing pressure on ED and hospital beds in an influenza peak season, by enabling fast patient flow and cohort isolation.

The use of in-hospital medical care for patients with metastasized colon, bronchus, or lung cancer.

PURPOSE: At the end of life, patients and their families tend to favor adequate pain and symptom management and attention to comfort measures over prolongation of life. However, it has been suggested that many cancer patients without curative options still receive aggressive treatment. We therefore aimed to describe the number of diagnostic procedures, hospitalization, and medication use among these patients as well as factors associated with receiving such care. METHODS: We conducted a cohort study on all patients with metastasized cancer from a primary colon or bronchus and lung (BL) neoplasm from the moment of first admittance (January-December 2017) to end of follow-up (November 2018) or death. RESULTS: A total of 408 patients with colon (36%) or BL (64%) cancer were included in this study, with a median survival time of 7.4 months. 93% of the patients were subjected to at least one diagnostic procedure, 49% received chemotherapy, and 56% received expensive medication including immunotherapy. Patients had a median of 4.6 hospital admissions and 2.3 emergency room (ER) visits. A quarter of all patients (n = 105) received specialized palliative care with a mean of 1.96 consultations and the first consultation after a median time of 4.1 months. Patients with BL neoplasms received significantly more diagnostic procedures, chemotherapy episodes, ER/ICU admissions, and more often received an end-of-life statement per person-year than patients with a primary colon neoplasm. Females received significantly less diagnostic procedures and visited the ER/ICU less frequently than males, and patients aged > 70 years received significantly less chemotherapy (episodes) and expensive medication than younger patients. No differences in care were found between different socioeconomic status groups. CONCLUSION: Patients with metastasized colon or BL cancer receive a large amount of in-hospital medical care. Specialized palliative care was initiated relatively late despite the incurable disease status of all patients. Factors associated with more procedures were BL neoplasms, age between 50 and 70, and male gender.

Clinical Sensitivity, Specificity and Epidemiology of SARS-CoV-2 Serological Testing Using the Biozek COVID-19 Test.

BACKGROUND: Clinical validation using the Biozek COVID-19 test including sensitivity and specificity and associated patient-reported symptoms with SARS-CoV-2 seropositivity. METHODS: 316 sera were analyzed including 47 hospitalized cases, 50 mild cases and 219 negative controls. Results were read visually by two technicians and in case of discrepancy by a third. Models were created between independent variables and IgG seropositivity using multivariable logistic regression analysis. RESULTS: Sensitivity of both IgM and IgG together for hospitalized patients at all time periods was 68.1% (32/47) and 90.0% (27/30) after 10 days or more. From mild/asymptomatic cases the combined IgM and IgG sensitivity was 92.0% (46/50) and 91.8% (45/49) after 10 days or more. In the group of non-COVID-19 cases, the overall specificity was 99.1% (217/219). For IgG alone, the specificity was 99.5% (218/219). In the multivariable analysis loss of smell remained the strongest associated variable with an odds ratio (95%CI): 6.82 (5.61-8.31), p-value < 0.001. Our final prediction model yielded a ROC-AUC of 0.77 (0.74-0.81) showing acceptable discrimination. CONCLUSIONS: The Biozek COVID-19 test showed high specificity and good sensitivity 10 days after the first sickness day. Solely IgM positive tests must be interpreted with caution and preferably excluded. In order to capture most symptomatic COVID-19 cases, loss of smell should be included within symptomatic screening policies.

Wide-scale study of 206 buildings in the Netherlands from 2011 to 2015 to determine the effect of drinking water management plans on the presence of Legionella spp.

Previous analysis of the Dutch National Legionella Outbreak Detection Program 2002-2012 has shown that buildings required to maintain a Legionella control plan for their drinking water installation are more likely to test positive for Legionella spp. Than buildings without such a plan (38% versus 22% of samples). To clarify this discrepancy, we analysed the results of mandatory water sample testing conducted as part of risk assessments in 206 buildings in the Netherlands from 2011 to 2015. Of the 6171 samples analysed, 16.2% exceeded the Dutch drinking water standard for Legionella spp. of 100 CFU/litre. In buildings with ≤50 tap points, the average percentage of samples containing ≥100 CFU/litre was 28.2%, and from buildings with >50 tap points, it was 12.2%. Analysis of serial samples (taken every 6 months) from each building showed that 33.2% of all buildings tested positive for at least one sample every 6 months. The overall increase was 4.4% per year. Analysis of Legionella subgroups showed that while the majority of positive samples contained L. non-pneumophila (96.9%), some samples did contain L. pneumophila serogroup 1 (1.0%) and serogroups 2-14 (2.1%). Our data suggest that the Dutch mandatory risk assessment and drinking water management plan is not sufficiently effective in preventing the proliferation of Legionella spp. and may even contribute to proliferation. This analysis should now be expanded to include other areas of the Netherlands in order to understand the geographical differences that we observed in our results, and why smaller buildings appear to be more likely to test positive for Legionella spp.

Association between rectal colonization with Highly Resistant Gram-negative Rods (HR-GNRs) and subsequent infection with HR-GNRs in clinical patients: A one year historical cohort study.

OBJECTIVE: Rectal colonization with Highly Resistant Gram-negative Rods (HR-GNRs) probably precedes infection. We aimed to assess the association between rectal HR-GNR colonization and subsequent HR-GNR infection in clinical patients during a follow-up period of one year in a historical cohort study design. METHODS: Rectal HR-GNR colonization was assessed by culturing. Subsequent development of infection was determined by assessing all clinical microbiological culture results extracted from the laboratory information system including clinical data regarding HR-GNR infections. A multivariable logistic regression model was constructed with HR-GNR rectal colonization as independent variable and HR-GNR infection as dependent variable. Gender, age, antibiotic use, historic clinical admission and previous (HR-GNR) infections were included as possible confounders. RESULTS: 1133 patients were included of whom 68 patients (6.1%) were colonized with a HR-GNR. In total 22 patients with HR-GNR infections were detected. Urinary tract infections were most common (n = 14, 63.6%), followed by bloodstream infections (n = 5, 22.7%) and other infections (n = 8, 36.4%). Eight out of 68 HR-GNR colonized patients (11.8%) developed a subsequent HR-GNR infection compared to 14 out of 1065 HR-GNR negative patients (1.3%), resulting in an odds ratio (95% CI) of 7.1 (2.8-18.1) in the multivariable logistic regression analyses. CONCLUSIONS: Rectal colonization with a HR-GNR was a significant risk factor for a subsequent HR-GNR infection. This implies that historical colonization culture results should be considered in the choice of empirical antibiotic therapy to include coverage of the cultured HR-GNR, at least in critically ill patients.

Evaluation of the Sofia Streptococcus pneumoniae FIA test for the detection of S. pneumoniae antigen in urine.

In this study, we evaluated the Sofia Streptococcus pneumoniae FIA test (Quidel Corporation, San Diego, CA, USA), a new immunofluorescence-based lateral flow test for the qualitative detection of S. pneumoniae antigen in urine or cerebrospinal fluid specimens. The analyses of 100 non-concentrated urine samples (including 50 samples from S. pneumoniae cases) showed a sensitivity and specificity (95 % CI) of, respectively, 66.0 % (52.2-77.6) and 100.0 % (92.9-100.0) for the Sofia test, and 62.0 % (48.2-74.1) and 98.0 % (89.5-99.7) for the BinaxNOW SPN Antigen Card. There were no significant differences in sensitivity and specificity between the tests (McNemar's tests, P=0.625 and P=1.000). In conclusion, this study indicates that the Streptococcus pneumoniae FIA test shows similar sensitivity and specificity rates compared to the BinaxNOW SPN Antigen Card.

Two Community Clusters of Legionnaires' Disease Directly Linked to a Biologic Wastewater Treatment Plant, the Netherlands.

A biologic wastewater treatment plant was identified as a common source for 2 consecutive Legionnaires' disease clusters in the Netherlands in 2016 and 2017. Sequence typing and transmission modeling indicated direct and long-distance transmission of Legionella, indicating this source type should also be investigated in sporadic Legionnaires' disease cases.

Gender differences in retention rate of tumor necrosis factor alpha inhibitor treatment in ankylosing spondylitis: a retrospective cohort study in daily practice.

AIM: To assess gender differences in ankylosing spondylitis (AS) patients in relation to tumor necrosis factor alpha inhibitor (TNFi) drug survival and occurrence of adverse events in daily practice in a large peripheral hospital. METHOD: Retrospective data were collected from AS patients treated with etanercept, infliximab and adalimumab between January 2004 and January 2014. Kaplan-Meier survival curves were conducted to describe the drug survival and occurrence of adverse events in time. RESULTS: Overall, 122 AS patients (60.7% male) were included over a 10-year time period, with a mean treatment period of 51 months (1-127 months). In total, 21 (17.2%) patients stopped the TNFi, mainly due to inefficacy (52.4%). Female patients showed a significant shorter treatment period compared to males (33.4 vs. 44.9 months). In addition, female patients switched more between TNFi compared to males (26.9% vs. 16.3%) and had a significantly higher risk at developing infections compared to male patients (26% vs.19%). CONCLUSION: Females stayed on the same TNFi for a significantly shorter period compared to males (33.4 vs. 44.9 months) and the most important reason to stop or switch the drug was inefficacy. Moreover, females seemed to be more prone to infections during TNFi treatment than males.

Growth of Legionella anisa in a model drinking water system to evaluate different shower outlets and the impact of cast iron rust.

Legionella continues to be a problem in water systems. This study investigated the influence of different shower mixer faucets, and the influence of the presence of cast iron rust from a drinking water system on the growth of Legionella. The research is conducted using a model of a household containing four drinking water systems. All four systems, which contained standard plumbing components including copper pipes and a water heater, were filled with unchlorinated drinking water. Furthermore, all systems had three different shower faucets: (A) a stainless-steel faucet, (B) a brass-ceramic faucet, and (C) a brass thermostatic faucet. System 1 was solely filled with drinking water. System 2 was filled with drinking water, and cast iron rust. System 3 was contaminated with Legionella, and system 4 was contaminated with a Legionella, and cast iron rust. During a period of 34 months, 450 cold water samples were taken from 15 sample points of the four drinking water systems, and tested for Legionella according to the Dutch Standard (NEN 6265). In system 4, with added cast iron rust, the stainless-steel mixer faucet (A) had the highest concentration of Legionella at >4.3log10CFU/l (>20,000CFU/l) and was positive in 46.4% of samples. In contrast, the stainless-steel mixer faucet (A) of system 3 without cast iron rust showed 14.3% positive samples with a maximum concentration of 3.9log10CFU/l (7600CFU/l) Legionella. Additionally, both contaminated systems (3 and 4), with the brass thermostatic faucet (C), tested positive for Legionella. System 3 in 85.7% of the samples, with a maximum concentration of 4.38log10CFU/l (24,200CFU/l), and system 4 in 64.3% of the samples with a maximum concentration of 4.13log10CFU/l (13.400CFU/l). These results suggest that both the type of faucet used in a drinking water system and the presence or absence of cast iron rust influence the growth of Legionella.

No nosocomial transmission under standard hygiene precautions in short term contact patients in case of an unexpected ESBL or Q&A E. coli positive patient: a one-year prospective cohort study within three regional hospitals.

BACKGROUND: Many Highly Resistant Gram Negative Rod (HR-GNR) positive patients are found unexpectedly in clinical cultures, besides patients who are screened and isolated based on risk factors. As unexpected HR-GNR positive patients are isolated after detection, transmission to contact patients possibly occurred. The added value of routine contact tracing in such situations within hospitals with standard hygiene precautions is unknown. METHODS: In 2014, this study was performed as a prospective cohort study. Index patients were defined as those tested unexpectedly HR-GNR positive in clinical cultures to diagnose a possible infection and were nursed under standard hygiene precautions before tested positive. After detection they were nursed in contact isolation. Contact patients were still hospitalized and shared the same room with the index patient for at least 12 h. HR-GNR screening was performed by culturing a rectal and throat swab. Clonal relatedness of HR-GNR isolates was determined using whole genome sequencing (WGS). RESULTS: Out of 152 unexpected HR-GNR positive patients, 35 patients (23.0%) met our inclusion criteria for index patient. ESBL E. coli was found most frequently (n = 20, 57.1%), followed by Q&A E. coli (n = 10, 28.6%), ESBL K. pneumoniae (n = 3, 8.5%), ESBL R. ornithinolytica (n = 1, 2.9%) and multi resistant P. aeruginosa (n = 1, 2.9%). After contact tracing, 69 patients were identified as contact patient of an index patient, with a median time between start of contact and sampling of 3 days. None were found HR-GNR positive by nosocomial transmission. CONCLUSIONS: In a local setting within hospitals with standard hygiene precautions, routine contact tracing among unexpected HR-GNR positive patients may be replaced by appropriate surveillance as we found no nosocomial transmission in short term contacts.

Clinical sensitivity and specificity of the Check-Points Check-Direct ESBL Screen for BD MAX, a real-time PCR for direct ESBL detection from rectal swabs.

Objectives: To determine the diagnostic accuracy of the Check-Direct ESBL Screen for BD MAX (ESBL qPCR) and an ESBL culture method to identify ESBLs directly from rectal swabs. Methods: Rectal swabs were obtained from clinical patients by performing cross-sectional (point)prevalence measurements in three regional hospitals. Rectal swabs were analysed by direct culture (ChromID ESBL agar) and with the ESBL qPCR. Suspected ESBL-producing isolates were confirmed with the combination disc method and analysed by WGS. Results: Out of 354 rectal swabs and 351 patients, 21 rectal swabs and 20 patients were positive for ESBL-producing isolates, resulting in a regional ESBL colonization prevalence of 5.7%. One rectal swab was false negative with the ESBL qPCR (blaTEM-12) and not covered by the ESBL qPCR. Eight ESBL qPCR-positive rectal swabs could not be confirmed by culture and were classified as false ESBL qPCR positive. The sensitivity and specificity of the ESBL qPCR were 95.2% (n = 20) and 97.6% (n = 323), respectively. When an optimal cycle threshold cut-off value of 37 was used, the ESBL qPCR displayed a sensitivity and specificity of 95.2% (n = 20) and 98.8% (n = 327), respectively (AUC = 0.975, 95% CI = 0.922-1). Conclusions: This ESBL qPCR offers rapid direct detection of the most prevalent ESBL types (blaCTX-M group and blaSHV group) from rectal swabs. The relatively high false-positive rate renders this test the most suitable as a screening test in high-prevalence regions or in an outbreak setting where a fast result is essential.