Background: Internationally, guidelines to prevent secondary transmission of Shigella infection vary widely. Cases, their contacts with diarrhoea, and those in certain occupational groups are frequently excluded from work, school, or daycare. In the Netherlands, all contacts attending pre-school (age 0–3) and junior classes in primary school (age 4–5), irrespective of symptoms, are also excluded pending microbiological clearance. We identified risk factors for secondary Shigella infection (SSI) within households and evaluated infection control policy in this regard. Methods: This retrospective cohort study of households where a laboratory confirmed Shigella case was reported in Amsterdam (2002–2009) included all households at high risk for SSI (i.e. any household member under 16 years). Cases were classified as primary, co-primary or SSIs. Using univariable and multivariable binomial regression with clustered robust standard errors to account for household clustering, we examined case and contact factors (Shigella serotype, ethnicity, age, sex, household size, symptoms) associated with SSI in contacts within households. Results: SSI occurred in 25/ 337 contacts (7.4%): 20% were asymptomatic, 68% were female, and median age was 14 years (IQR: 4–38). In a multivariable model adjusted for case and household factors, only diarrhoea in contacts was associated with SSI (IRR 8.0, 95% CI:2.7-23.8). In a second model, factors predictive of SSI in contacts were the age of case (0–3 years (IRR_{case≥6 years}:2.5, 95% CI:1.1-5.5) and 4–5 years (IRR_{case≥6 years}:2.2, 95% CI:1.1-4.3)) and household size (>6 persons (IRR_{2-4 persons} 3.4, 95% CI:1.2-9.5)). Conclusions: To identify symptomatic and asymptomatic SSI, faecal screening should be targeted at all household contacts of preschool cases (0–3 years) and cases attending junior class in primary school (4–5 years) and any household contact with diarrhoea. If screening was limited to these groups, only one asymptomatic adult carrier would have been missed, and potential exclusion of 70 asymptomatic contacts <6 years old from school or daycare, who were contacts of cases of all ages, could have been avoided.

From 2006 to 2008,Neisseria gonorrhoeaeisolates were identified with decreased susceptibility to the extended-spectrum cephalosporin (ESC) cefotaxime among visitors of the Amsterdam sexually transmitted infections (STI) clinic, the Netherlands. Spread, clonality, and characteristics of 202 isolates were examined using antibiograms, conventionalpenAmosaic gene PCR, andN. gonorrhoeaemultiple-locus variable-number tandem repeat analysis (NG-MLVA). A strictly defined subset was further characterized byN. gonorrhoeaemultiantigen sequence typing (NG-MAST) and sequencing of ESC resistance determinants (penA,mtrR, andporB1b). Seventy-fourN. gonorrhoeaeisolates with a cefotaxime MIC of >0.125 μg/ml (group A), 54 with a cefotaxime MIC of 0.125 μg/ml (group B), and a control group of 74 with a cefotaxime MIC of <0.125 μg/ml (group C) were included. Fifty-three clonally relatedpenAmosaic-positive isolates (penicillin-binding protein 2 type XXXIV) were identified in group A (n= 47 isolates; 64%) and B (n= 6 isolates; 11%). The 53penAmosaic-positive isolates were predominantly NG-MAST ST1407 (87%) and contained anmtrRpromoter A deletion (98%) andporB1balterations G101K/A102N. All were assigned to the same NG-MLVA cluster that comprised in total 56 isolates. A correlation was found between decreased cefotaxime susceptibility and ST1407 that was highly prevalent among visitors of the Amsterdam STI clinic. The rapid spread of this strain, which also has been identified in many other countries, might be facilitated by high-risk sexual behavior and should be monitored closely to identify potential treatment failure. Quality-assured surveillance of ESC susceptibility on the national and international levels and exploration of new drugs and/or strategies for treatment of gonorrhea are crucial.

Nucleic acid amplification tests (NAATs) are recommended to diagnose Neisseria gonorrhoeae infections because of superior sensitivity. Increasing NAAT use causes a decline of crucial antimicrobial resistance (AMR) surveillance data, which rely on culture. We analyzed the suitability of the ESwab system for NAAT diagnostics and deferred targeted N. gonorrhoeae culture, to allow selective and efficient culture based on NAAT results. We included patients visiting the STI Clinic Amsterdam, The Netherlands, in 2013. Patient characteristics and urogenital and rectal samples for direct N. gonorrhoeae culture, standard NAAT and ESwab were collected. Standard NAAT and NAAT on ESwab samples were performed using the APTIMA Combo 2 assay for N. gonorrhoeae and Chlamydia trachomatis. Two deferred N. gonorrhoeae cultures were performed on NAAT positive ESwab samples, after storage at 4°C for 1-3 days. We included 2452 samples from 1893 patients. In standard NAAT 107 samples were N. gonorrhoeae and 284 were C. trachomatis positive. The respective sensitivities of NAAT on ESwab were 83% (95%-CI: 75-90%) and 87% (95%-CI: 82-90%). ESwab samples were available for 98 of the gonorrhoea positive samples. Of these, 82% were positive in direct culture, 69% and 56% were positive in deferred culture (median storage time: 27 and 48 hours, respectively). Deferred culture was more often successful in urogenital samples or when the patient had symptoms at the sampling site. Deferred N. gonorrhoeae culture of stored ESwab samples is feasible and enables AMR surveillance. To limit loss of NAAT sensitivity we recommend obtaining separate samples for NAAT and deferred culture.

One third of travellers to low- and middle-income regions of the tropics and subtropics become colonized by extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). The risk varies by destination and, for each traveller, may be substantially further increased by travellers’ diarrhoea (TD) and antibiotic use. Despite the risk of TD in Africa, ESBL-PE acquisition rates in all studies are lower there than in Asia. Africa has become increasingly popular as a destination for international travellers, yet minimal data are available from the continent’s subregions and countries. We analysed subregion- and country-specific data on carriage and risk factors for ESBL-PE colonization pooled from three prospective studies conducted between 2009 and 2013 among Finnish and Dutch travellers. The data were subjected to multivariable analysis of risk factors. In addition, we compared our data to two recent large investigations reporting data by subregion and country. Our joint analysis comprised data on 396 travellers. The ESBL-PE colonization rate was highest in Northern Africa, followed by Middle and Eastern Africa, and lowest in Southern and Western Africa. Of individual countries with more than 15 visitors, the highest rates were seen for Egypt (12/17; 70.6%), Ghana (6/23; 26.1%), and Tanzania (14/81; 17.3%); the rates among travellers to Egypt were comparable to those reported in South and Southeast Asia. In a pooled multivariable analysis, travel destination, age, overnight hospitalisation abroad, TD, and use of fluoroquinolones were independently associated with increased ESBL-PE colonization rates. Even in areas with relatively low risk of colonization, antimicrobials clearly predispose to colonization with ESBL-PE. Travellers to Africa should be cautioned against unnecessary use of antibiotics.