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Diagnosis of bone and joint infections (BJI) relies on microbiological culture which has a long turnaround time and is challenging for certain bacterial species. Rapid molecular methods may alleviate these obstacles. Here, we investigate the diagnostic performance of IS-pro, a broad-scope molecular technique that can detect and identify most bacteria to the species level. IS-pro additionally informs on the amount of human DNA present in a sample, as a measure of leukocyte levels. This test can be performed in 4 h with standard laboratory equipment. Residual material of 591 synovial fluid samples derived from native and prosthetic joints from patients suspected of joint infections that were sent for routine diagnostics was collected and subjected to the IS-pro test. Bacterial species identification as well as bacterial load and human DNA load outcomes of IS-pro were compared to those of culture. At sample level, percent positive agreement (PPA) between IS-pro and culture was 90.6% (95% CI 85.7- to 94%) and negative percent agreement (NPA) was 87.7% (95% CI 84.1 to 90.6%). At species level PPA was 80% (95% CI 74.3 to 84.7%). IS-pro yielded 83 extra bacterial detections over culture for which we found supporting evidence for true positivity in 40% of the extra detections. Missed detections by IS-pro were mostly related to common skin species in low abundance. Bacterial and human DNA signals measured by IS-pro were comparable to bacterial loads and leukocyte counts reported by routine diagnostics. We conclude that IS-pro showed an excellent performance for fast diagnostics of bacterial BJI.Diagnosis of bone and joint infections (BJI) relies on microbiological culture which has a long turnaround time and is challenging for certain bacterial species. Rapid molecular methods may alleviate these obstacles.

Background: Viruses and bacteria from the nasopharynx are capable of causing community-acquired pneumonia (CAP), which can be difficult to diagnose. We aimed to investigate whether shifts in the composition of these nasopharyngeal microbial communities can be used as diagnostic biomarkers for CAP in adults., Methods: We collected nasopharyngeal swabs from adult CAP patients and controls without infection in a prospective multicenter case-control study design. We generated bacterial and viral profiles using 16S ribosomal RNA gene sequencing and multiplex polymerase chain reaction (PCR), respectively. Bacterial, viral, and clinical data were subsequently used as inputs for extremely randomized trees classification models aiming to distinguish subjects with CAP from healthy controls., Results: We enrolled 117 cases and 48 control subjects. Cases displayed significant beta diversity differences in nasopharyngeal microbiota (P = .016, R2 = .01) compared to healthy controls. Our extremely randomized trees classification models accurately discriminated CAP caused by bacteria (area under the curve [AUC] .83), viruses (AUC .95) or mixed origin (AUC .81) from healthy control subjects. We validated this approach using a dataset of nasopharyngeal samples from 140 influenza patients and 38 controls, which yielded highly accurate (AUC .93) separation between cases and controls., Conclusions: Relative proportions of different bacteria and viruses in the nasopharynx can be leveraged to diagnose CAP and identify etiologic agent(s) in adult patients. Such data can inform the development of a microbiota-based diagnostic panel used to identify CAP patients and causative agents from nasopharyngeal samples, potentially improving diagnostic specificity, efficiency, and antimicrobial stewardship practices., peer-reviewed

Recurrent urinary tract infections (rUTI) largely contribute to antibiotic use in older adults. Understanding the genetic characteristics ofThis is a secondary analysis of a multicenter Dutch nursing home study (PROGRESS).In total, 121Recurrent UTI in nursing home residents are caused by same-strain

Background Quantitative PCR (qPCR) aims to measure the DNA or RNA concentration in diagnostic and biological samples based on the quantification cycle (Cq) value observed in the amplification curves. Results of qPCR experiments are regularly calculated as if all assays are 100% efficient or reported as just Cq, ΔCq, or ΔΔCq values. Contents When the reaction shows specific amplification, it should be deemed to be positive, regardless of the observed Cq. Because the Cq is highly dependent on amplification efficiency that can vary among targets and samples, accurate calculation of the target quantity and relative gene expression requires that the actual amplification efficiency be taken into account in the analysis and reports. PCR efficiency is frequently derived from standard curves, but this approach is affected by dilution errors and hampered by properties of the standard and the diluent. These factors affect accurate quantification of clinical and biological samples used in diagnostic applications and collected in challenging conditions. PCR efficiencies determined from individual amplification curves avoid these confounders. To obtain unbiased efficiency-corrected results, we recommend absolute quantification with a single undiluted calibrator with a known target concentration and efficiency values derived from the amplification curves of the calibrator and the unknown samples. Summary For meaningful diagnostics or biological interpretation, the reported results of qPCR experiments should be efficiency corrected. To avoid ambiguity, the Minimal Information for Publications on Quantitative Real-Time PCR Experiments (MIQE) guidelines checklist should be extended to require the methods that were used (1) to determine the PCR efficiency and (2) to calculate the reported target quantity and relative gene expression value.

Early detection of bacterial transmission and outbreaks in hospitals is important because nosocomial infections can result in health complications and longer hospitalization. Current practice to detect outbreaks uses genotyping methods amplified fragment length polymorphism (AFLP) and whole genome sequencing (WGS), which are not suitable methods for real-time transmission screening of both susceptible and resistant bacteria. The aim was to assess the typing technique Fourier transform infrared (FTIR) spectroscopy as real-time screening method to discriminate large amounts of susceptible and resistant bacteria at strain level when there is no evident outbreak in comparison with the WGS reference. Isolates of past hospital outbreak strains of Acinetobacter baumannii/calcoaceticus complex (n = 25), Escherichia coli (n = 31), Enterococcus faecium (n = 22), Staphylococcus aureus (n = 37) and Pseudomonas aeruginosa (n = 30) were used for validation of FTIR. Subsequently, Enterococcus faecalis (n = 106) and Enterococcus faecium (n = 104) isolates from weekly routine screening samples when no potential outbreak was present were analysed. FTIR showed reproducibility and congruence of cluster composition with WGS for A. baumannii/calcoaceticus complex and E. faecium outbreak isolates. The FTIR results of E. faecalis and E. faecium isolates from routine samples showed reproducibility, but the congruence of cluster composition with WGS was low. For A. baumannii/calcoaceticus complex and E. faecium outbreak isolates, FTIR appears to be a discriminatory typing tool. However, our study shows the discriminatory power is too low to screen real-time for transmission of E. faecium and E. faecalis at patient wards based on isolates acquired in routine surveillance cultures when there is no clear suspicion of an ongoing outbreak.

Background Clostridioides difficile is the most common cause of nosocomial diarrhea. Ribotyping of cultured strains by a PCR-based test is used to study potential transmission between patients. We aimed to develop a rapid test that can be applied directly on fecal samples for simultaneous detection and ribotyping of C. difficile, as well as detection of toxin genes. Methods We developed a highly specific and sensitive primer set for simultaneous detection and ribotyping of C. difficile directly on total fecal DNA. Toxin genes were detected with primers adapted from Persson et al. (Clin Microbiol Infect 14(11):1057–1064). Our study set comprised 130 fecal samples: 65 samples with positive qPCR for C. difficile toxin A/B genes and 65 C. difficile qPCR negative samples. PCR products were analyzed by capillary gel electrophoresis. Results Ribosomal DNA fragment peak profiles and toxin genes were detected in all 65 C. difficile positive fecal samples and in none of the 65 C. difficile negative samples. The 65 samples were assigned to 27 ribotypes by the Dutch reference laboratory. Our peak profiles corresponded to these ribotypes, except for two samples. During a C. difficile outbreak, patients were correctly allocated to the outbreak-cluster based on the results of direct fecal ribotyping, before C. difficile isolates were cultured and conventionally typed. Conclusion C. difficile ribotyping directly on fecal DNA is feasible, with sensitivity and specificity comparable to that of diagnostic toxin gene qPCR and with ribotype assignment similar to that obtained by conventional typing on DNA from cultured isolates. This supports simultaneous diagnosis and typing to recognize an outbreak.

A proportion of patients suspected of Clostridium difficile infection are unnecessarily placed in contact isolation. By introducing a random-access glutamate dehydrogenase (GDH) test for C. difficile, we aimed to reduce isolation time. In addition, we investigated whether the result of the toxin A&B enzyme immunoassay (EIA) was associated with the decision to initiate antibiotic treatment against C. difficile. This retrospective pre- and post-implementation study was from June 3, 2016, to June 4, 2018. Pre-implementation, only a NAAT was performed. In the post-implementation period, a GDH test was performed; if positive, a toxin A&B EIA followed the same day and subsequently a NAAT. Contact isolation for CDI was discontinued when the GDH test was negative. Median time in isolation was 50.8 h pre-implementation (n = 189) versus 28.0 h post-implementation (n = 119), p C. difficile were initiated versus 4/28 (14.3%) patients who were NAAT, GDH and toxin A&B EIA positive. Introducing a random-access screening test resulted in a significant decrease in patient isolation time. The GDH test had a high negative predictive value making it suitable to determine whether contact isolation can be discontinued. Furthermore, the result of a toxin A&B EIA had limited added value on the percentage of patients in whom antibiotic treatment against C. difficile was initiated.

Purpose. Bacterial vaginosis (BV) is a common clinical condition characterized by odorous vaginal discharge, vaginal itching and/or burning. BV can occur when vaginal lactobacilli are depleted and replaced by diverse anaerobic bacteria. We evaluated a commercial multiplex PCR (ATRiDA) for the diagnosis of BV. Methods. Cervicovaginal samples were included from women reporting urogenital symptoms and from women notified for sexually transmitted infections (STI) – who were not (necessarily) symptomatic. Clinical BV diagnoses were obtained from electronic patient files. The ATRiDA test measures the loads of Gardnerella vaginalis, Atopobium vaginae and Lactobacillus species in relation to overall bacterial load. The ATRiDA test outcome was compared to the clinical BV diagnosis and to vaginal microbiota composition, determined by 16SrRNA gene sequencing. Results. We included samples from 185 women reporting urogenital symptoms, of whom 81 had BV and 93 women who were notified for an STI, of whom 16 had BV. Overall, compared to the clinical BV diagnosis, the ATRiDA test demonstrated high sensitivity (96.9 %) and moderate specificity (70.2 %). The negative predictive value was high (>97.3). The positive predictive value differed by study group and was highest in women reporting urogenital symptoms (78.2 %). Sequencing showed that 54 % of women who had an ATRiDA BV-positive test outcome, but who were not clinically diagnosed with BV, had diverse anaerobic vaginal microbiota (asymptomatic vaginal dysbiosis). Conclusion. The ATRiDA test is a sensitive method for the detection of BV but, given the high occurrence of asymptomatic vaginal dysbiosis, a positive test outcome should be interpreted together with clinical symptoms.

Background: Detecting SARS-CoV-2 antibodies may help to diagnose COVID-19. Head-to-head validation of different types of immunoassays in well-characterized cohorts of hospitalized patients remains needed. Methods: We validated three chemiluminescence immunoassays (CLIAs) (Liaison, Elecsys, and Abbott) and one single molecule array assay (SIMOA) (Quanterix) for automated analyzers, one rapid immunoassay RIA (AllTest), and one ELISA (Wantai) in parallel in first samples from 126 PCR confirmed COVID-19 hospitalized patients and 158 pre-COVID-19 patients. Specificity of the AllTest was also tested in 106 patients with confirmed parasitic and dengue virus infections. Specificity of the Wantai assay was not tested due to limitations in sample volumes. Results: Overall sensitivity in first samples was 70.6 % for the Liaison, 71.4 % for the Elecsys, 75.4 % for the Abbott, 70.6 % for the Quanterix, 77.8 % for the AllTest, and 88.9 % for the Wantai assay, respectively. Sensitivity was between 77.4 % (Liaison) and 94.0 % (Wantai) after 10 dpso. No false positive results were observed for the Elecsys and Abbott assays. Specificity was 91.1 % for the Quanterix, 96.2 % for the Liaison, and 98.1 % for the AllTest assay, respectively. Conclusion: We conclude that low sensitivity of all immunoassays limits their use early after onset of illness in diagnosing COVID-19 in hospitalized patients. After 10 dpso, the Wantai ELISA has a relatively high sensitivity, followed by the point-of-care AllTest RIA that compares favorably with automated analyzer immunoassays.

IntroductionThis prospective study aimed to study the composition and structure of the vaginal microbiota prior to Chlamydia trachomatis infection.MethodsA nested case–control study was performed in 122 women, half of which acquired C. trachomatis within a year after their first visit. At the first visit, the composition and structure of vaginal microbial communities were analysed using 16S rRNA sequencing in the context of the sociodemographic and sexual risk behaviour information using logistic regression.ResultsFive vaginal community state types (CSTs) were identified. Four CSTs were dominated by Lactobacillus spp., of which L. crispatus (37%) and L. iners (33%) were the most common. One CST was characterised by the absence of Lactobacillus spp. (25%) and the presence of an array of strict and facultative anaerobes. Multivariate logistic regression analysis revealed that women with a L. iners-dominated CST had an increased risk of C. trachomatis infection (p=0.04; OR: 2.6, 95% CI 1.0 to 6.6).ConclusionsThe distribution of CSTs dominated by Lactobacillus spp. agreed with previous studies. However, the frequency of dysbiosis among Caucasian women was relatively high (24%). Having vaginal microbiota dominated by L. iners was associated with an increased risk for C. trachomatis infection. Therefore, we hypothesise that specific signatures of vaginal microbiota are indicative of increased host predisposition to acquiring STIs.

Background. Increasing evidence suggests that the cervicovaginal microbiota (CVM) plays an important role in acquiring sexually transmitted infections (STIs). Here we study the CVM in a population of women notified by a sex partner for Chlamydia trachomatis infection. Methods. We included 98 women who were contact-traced by C. trachomatis-positive sex partners at the STI outpatient clinic in Amsterdam, the Netherlands, and analyzed their cervicovaginal samples and clinical data. CVMs were characterized by sequencing the V3/V4 region of the 16S ribosomal RNA gene and by hierarchical clustering. Characteristics associating with C. trachomatis infection were examined using bivariable and multivariable logistic regression analysis. Results. The CVM was characterized for 93 women, of whom 52 tested C. trachomatis positive and 41 C. trachomatis negative. We identified 3 major CVM clusters. Clustered CVM predominantly comprised either diverse anaerobic bacteria (n = 39 [42%]), Lactobacillus iners (n = 32 [34%]), or Lactobacillus crispatus (n = 22 [24%]). In multivariable analysis, we found that CVM was significantly associated with C. trachomatis infection (odds ratio [OR], 4.2 [95% confidence interval {CI}, 1.2-15.4] for women with diverse anaerobic CVM and OR, 4.4 [95% CI, 1.3-15.6], for women with L. iners-dominated CVM, compared with women with L. crispatus-dominated CVM), as was younger age (OR, 3.1 [95% CI, 1.1-8.7] for those ≤21 years old) and reporting a steady sex partner (OR, 3.6 [95% CI, 1.4-9.4]). Conclusions. Women who tested positive for Chlamydia trachomatis infection after having been contact-traced by a chlamydiapositive partner were more likely to have CVM dominated by L. iners or by diverse anaerobic bacteria, than by L. crispatus.

Background Recognition of nosocomial outbreaks with antimicrobial resistant (AMR) pathogens and appropriate infection prevention measures are essential to limit the consequences of AMR pathogens to patients in hospitals. Because unrelated, but genetically similar AMR pathogens may circulate simultaneously, rapid high-resolution molecular typing methods are needed for outbreak management. We compared amplified fragment length polymorphism (AFLP) and whole genome sequencing (WGS) during a nosocomial outbreak of vancomycin-resistant Enterococcus faecium (VRE) that spanned 5 months. Methods Hierarchical clustering of AFLP profiles was performed using unweighted pair-grouping and similarity coefficients were calculated with Pearson correlation. For WGS-analysis, core single nucleotide polymorphisms (SNPs) were used to calculate the pairwise distance between isolates, construct a maximum likelihood phylogeny and establish a cut-off for relatedness of epidemiologically linked VRE isolates. SNP-variations in the vanB gene cluster were compared to increase the comparative resolution. Technical replicates of 2 isolates were sequenced to determine the number of core-SNPs derived from random sequencing errors. Results Of the 721 patients screened for VRE carriage, AFLP assigned isolates of 22 patients to the outbreak cluster. According to WGS, all 22 isolates belonged to ST117 but only 21 grouped in a tight phylogenetic cluster and carried vanB resistance gene clusters. Sequencing of technical replicates showed that 4–5 core-SNPs were derived by random sequencing errors. The cut-off for relatedness of epidemiologically linked VRE isolates was established at ≤7 core-SNPs. The discrepant isolate was separated from the index isolate by 61 core-SNPs and the vanB gene cluster was absent. In AFLP analysis this discrepant isolate was indistinguishable from the other outbreak isolates, forming a cluster with 92% similarity (cut-off for identical isolates ≥90%). The inclusion of the discrepant isolate in the outbreak resulted in the screening of 250 patients and quarantining of an entire ward. Conclusion AFLP was a rapid and affordable screening tool for characterising hospital VRE outbreaks. For in-depth understanding of the outbreak WGS was needed. Compared to AFLP, WGS provided higher resolution typing of VRE isolates with implications for outbreak management.

Introduction Of female visitors to the STI clinic in Amsterdam, 31% report use of vaginal cleansing products (including douches). Vaginal douching may negatively affect vaginal microbiota compositions (VM). We report the effect of intra-vaginal douching on the VM in a prospective study. Methods Through advertisements, we recruited 25 healthy women, aged 18–36 years, from 2015–2016. Participants were followed over 3 menstrual cycles and were instructed to use an intra-vaginal lactic-acid-containing douche 3 times a week during the 2nd cycle. Participants self-collected a median of 68 [IQR: 64–68] vaginal swabs. Baseline characteristics were collected through questionnaires. All participants kept a daily diary in which they reported douching, menstruation, sexual activity, etc. VM were assessed by 16S rRNA (V3-V4 region) sequencing. Associations between douching and VM were assessed by multivariable logistic regression, using generalised estimating equations to account for multiple observations within the same individual. Results As of December 2016, a median of 42 [IQR:40–44] vaginal swabs from 10/25 women were analysed. These 10 women had a median age of 25 years [IQR: 21.8–29.3], 9 women were Dutch-Caucasian, 9 used hormonal contraceptives and all were highly educated. At baseline, 8 women had lactobacilli-dominated VM ( Lactobacillus crispatus (n=6), L. iners (n=1) or L. iners / L. jensenii (n=1)) and 2 women had polybacterial Gardnerella vaginalis -containing VM (GV-VM). The latter 2 women continued to have GV-VM throughout the study period. The VMs of 2 women, dominated either by L. crispatus or L. iners at baseline, shifted to GV-VM during the 2nd cycle, which persisted in the 3rd cycle. Having GV-VM was more likely in the 2nd and 3rd cycle, compared to the 1 st cycle, after adjusting for sex and menses (odds ratio (OR)=1.7 (95% CI: 0.9–3.1) and OR=2.1 (95% CI: 0.7–6.1), respectively), though not statistically significanctly so. Conclusion Our interim analyses suggest that regular intra-vaginal douching may promote a shift from lactobacilli-dominated VM to GV-VM.

Objectives The selective vaccination programme against hepatitis B virus (HBV) was introduced in the Netherlands in 2002 targeting high-risk groups, including men who have sex with men (MSM). Despite the high average age of vaccination in MSM, the number of notifications of acute HBV recently declined. We investigate whether this can be attributed to the selective vaccination programme. We examine how vaccination strategies could be improved and the impact of universal infant vaccination introduced in 2011. Methods We use a mathematical model for HBV transmission among MSM. The incidence of HBV was calculated from the model and from notification data of acute HBV. Results A decline was observed in the incidence of HBV since 2006, as calculated from the model; this decline was smaller than that observed in data if all MSM were equally likely to be vaccinated. Assuming that high-risk MSM were more likely to be vaccinated than low-risk MSM resulted in a steeper decline in modelled incidence and better agreement with observed incidence. Vaccinating MSM at a younger age or doubling the vaccination rate would increase the impact of selective vaccination, but is less effective than vaccinating high-risk MSM. Conclusions Selective HBV vaccination of MSM in the Netherlands has had a substantial impact in reducing HBV incidence. The reduction suggests that vaccination rates among high-risk MSM were higher than those among low-risk MSM. Countries that have not yet reached 35-year cohorts with universal childhood vaccination should actively implement or continue selective high-risk MSM vaccination.

Background An outbreak of Clostridium difficile ribotype 027 infection (CDI) occurred at an university hospital, involving 19 departments. To determine what hospital-associated factors drove the outbreak of this particular strain we performed a case-control study. Methods Cases (n = 79), diagnosed with CDI due to C. difficile ribotype 027 were matched for age and treating medical specialty to four control patients (n = 316). Patients diagnosed with CDI due to other ribotypes were included as a second control group. A random selection of C. difficile ribotype 027 strains (n = 10) was genotyped by Whole Genome Sequencing (WGS). Findings WGS showed the outbreak was likely caused by a single strain of C. difficile (two or less single-nucleotide variants between isolates). Ninety-five percent of cases had used antibiotics, compared to 56% of controls. Previous admission to the intensive care unit (ICU) (OR: 2.4, 95% CI 1.0–5.6), longer length of stay (LOS), and recent hospital admission were associated with CDI ribotype 027. Cases were less likely to have been admitted to a ward with a known isolated CDI patient (OR: 0.2, 95% CI 0.1–0.6). Analysis of patients who stayed at the ICU (35 cases; 51 controls), indicated that the use of selective decontamination of the digestive tract (SDD) and a longer LOS in the ICU were associated with CDI risk. Interpretation In this large outbreak, any antibiotic use, including SDD use, appeared as a prerequisite for acquisition of the outbreak strain. The role of use of SDD and prolonged stay on the ICU could not be disentangled, but both factors can play a biologically plausible role in C. difficile acquisition and infection.

Background & Aims: In low endemic countries, most hepatitis B virus (HBV) infections are found in adult behavioural risk groups, such as drug users (DU) and men having sex with men (MSM). These risk groups are frequently exposed to HBV, which might induce a different rate of viral clearance compared with the general adult population, in whom the chronicity rate is estimated to be 5-10%. Our aim was to obtain insights into the proportion of MSM and DU developing chronic infection after a primary HBV infection, and the underlying risk factors. Methods: From 1984 to 2002, sera of 1862 MSM and 1268 DU of the Amsterdam Cohort Studies were retrospectively tested for anti-HBc, HBsAg, and HBV DNA. As of 2003, all of the cohort participants were vaccinated, making further testing redundant. Results: Hundred and forty seven participants seroconverted for anti-HBc during follow-up. The median age at the moment of the acute infection was 31 years. The proportion of those becoming chronically infected was 23% and 28% for MSM and DU, respectively. In both cohorts, being younger was a risk factor for developing chronic infection (OR: 0.9; 95% CI: 0.82-0.99). HIV/HCV co-infection was associated with developing chronic HBV infection in the DU cohort (OR: 32.1, 95% CI: 3.1-334.5). Conclusions: Compared with the general population, MSM and DU had an unanticipated high rate of developing chronic HBV infections. HIV/HCV co-infection proved to be an important risk factor for developing chronic HBV infections in DU. The reason for the high rate of MSM becoming chronically infected remains unclear. (C) 2012 European Association for the Study of the Liver. Published by Elsevier B. V. All rights reserved

To evaluate hepatitis B virus (HBV) risk group vaccination in Amsterdam, which started in 1998, we examined 342 reported acute HBV-cases and sequenced 85 DNA isolates. The reported number of cases declined from 214 in 1992-1997 to 128 in 1998-2003, due to a decline in injecting drug users (IDU) and their heterosexual partners. Phylogenetic analyses showed that after 1998, the IDU cluster nearly disappeared, probably due to a decline in injecting. Acute HBV remained stable among men having sex with men; given their increased sexual risk behavior, vaccination has probably prevented an increase in their acute infections. Currently, 48-72% of the people who should be included in the program are still susceptible to HBV.

Background Egypt has high prevalence of hepatitis C virus (HCV) infection and intermediate prevalence of hepatitis B virus (HBV) infection; however, infection prevalence among Egyptian migrants is unknown. Considering the asymptomatic onset and development of disease in chronically-infected patients, many may remain undiagnosed. Aims To evaluate an HCV- and HBV-screening programme designed to identify undetected infections among first-generation Egyptian migrants in Amsterdam, the Netherlands. Methods In 2009 and 2010, viral hepatitis educational and screening sessions were established at Egyptian meeting places. Data regarding demographics and HCV risk factors were collected. Chronically infected participants were referred and followed up. Phylogenetic analyses were used to ascertain the geographic origin of infections. Results Eleven of 465 (2.4%; 95% CI = 1.3–4.2%) migrants had HCV antibodies; 10/11 were HCV RNA positive. All had genotype 4a, and strains were typical of those of Egypt and the Middle East. Older age and exposure to parenteral antischistosomal therapy (PAT) were significantly associated with HCV. Anti-HBc prevalence was 16.8% (95% CI = 13.7–20.4%); HBsAg prevalence was 1.1% (95% CI = 0.5–2.5%). All had genotype D, typical of those of the Middle East. Most (9/10 HCV; 3/5 HBV) chronic infections were newly diagnosed; four of the HCV-infected individuals started treatment. Conclusions Anti-HCV and HBsAg prevalence among Egyptian migrants was lower compared with the general Egyptian population, but higher than the general population of Western countries. Phylogenetic analyses suggest that all infections were from the region of origin. HCV-screening programmes should target first-generation Egyptian migrants, especially those of older age and those who received PAT.

The effect of vaccination programs on transmission of infectious disease is usually assessed by monitoring programs that rely on notifications of symptomatic illness. For monitoring of infectious diseases with a high proportion of asymptomatic cases or a low reporting rate, molecular sequence data combined with modern coalescent-based techniques offer a complementary tool to assess transmission. Here, the authors investigate the added value of using viral sequence data to monitor a vaccination program that was started in 1998 and was targeted against hepatitis B virus in men who have sex with men in Amsterdam, the Netherlands. The incidence in this target group, as estimated from the notifications of acute infections with hepatitis B virus, was low; therefore, there was insufficient power to show a significant change in incidence. In contrast, the genetic diversity, as estimated from the viral sequence collected from the target group, revealed a marked decrease after vaccination was introduced. Taken together, the findings suggest that introduction of vaccination coincided with a change in the target group toward behavior with a higher risk of infection. The authors argue that molecular sequence data provide a powerful additional monitoring instrument, next to conventional case registration, for assessing the impact of vaccination.

Background Although published results are inconsistent, it has been suggested that tattooing and piercing are risk factors for HBV and HCV infections. To examine whether tattooing and piercing do indeed increase the risk of infection, we conducted a study among people with multiple tattoos and/or piercings in the Netherlands who acquired their tattoos and piercings in the Netherlands and/or abroad. Methods Tattoo artists, piercers, and people with multiple tattoos and/or piercings were recruited at tattoo conventions, shops (N = 182), and a biannual survey at our STI-outpatient clinic (N = 252) in Amsterdam. Participants were interviewed and tested for anti-HBc and anti-HCV. Determinants of HBV and HCV infections were analysed using logistic regression analysis. Results The median number of tattoos and piercings was 5 (IQR 2–10) and 2 (IQR 2–4), respectively. Almost 40% acquired their tattoo of piercing abroad. In total, 18/434 (4.2%, 95%CI: 2.64%–6.46%) participants were anti-HBc positive and 1 was anti-HCV positive (0.2%, 95%CI: 0.01%–1.29%). Being anti-HBc positive was independently associated with older age (OR 1.68, 95%CI: 1.03–2.75 per 10 years older) and being born in an HBV-endemic country (OR 7.39, 95%CI: 2.77–19.7). Tattoo- and/or piercing-related variables, like having a tattoo or piercing in an HBV endemic country, surface percentage tattooed, number of tattoos and piercings etc., were not associated with either HBV or HCV. Conclusions We found no evidence for an increased HBV/HCV seroprevalence among persons with multiple tattoos and/or piercings, which might be due to the introduction of hygiene guidelines for tattoo and piercing shops in combination with the low observed prevalence of HBV/HCV in the general population. Tattoos and/or piercings, therefore, should not be considered risk factors for HBV/HCV in the Dutch population. These findings imply the importance of implementation of hygiene guidelines in other countries.