Completed genome and emergence scenario of the multidrug-resistant nosocomial pathogen Staphylococcus epidermidis ST215.

BACKGROUND: A multidrug-resistant lineage of Staphylococcus epidermidis named ST215 is a common cause of prosthetic joint infections and other deep surgical site infections in Northern Europe, but is not present elsewhere. The increasing resistance among S. epidermidis strains is a global concern. We used whole-genome sequencing to characterize ST215 from healthcare settings. RESULTS: We completed the genome of a ST215 isolate from a Swedish hospital using short and long reads, resulting in a circular 2,676,787 bp chromosome and a 2,326 bp plasmid. The new ST215 genome was placed in phylogenetic context using 1,361 finished public S. epidermidis reference genomes. We generated 10 additional short-read ST215 genomes and 11 short-read genomes of ST2, which is another common multidrug-resistant lineage at the same hospital. We studied recombination's role in the evolution of ST2 and ST215, and found multiple recombination events averaging 30-50 kb. By comparing the results of antimicrobial susceptibility testing for 31 antimicrobial drugs with the genome content encoding antimicrobial resistance in the ST215 and ST2 isolates, we found highly similar resistance traits between the isolates, with 22 resistance genes being shared between all the ST215 and ST2 genomes. The ST215 genome contained 29 genes that were historically identified as virulence genes of S. epidermidis ST2. We established that in the nucleotide sequence stretches identified as recombination events, virulence genes were overrepresented in ST215, while antibiotic resistance genes were overrepresented in ST2. CONCLUSIONS: This study features the extensive antibiotic resistance and virulence gene content in ST215 genomes. ST215 and ST2 lineages have similarly evolved, acquiring resistance and virulence through genomic recombination. The results highlight the threat of new multidrug-resistant S. epidermidis lineages emerging in healthcare settings.

Outbreak of Salmonella Typhimurium linked to Swedish pre-washed rocket salad, Sweden, September to November 2022.

In September 2022, the Public Health Agency of Sweden observed an increase in domestic Salmonella Typhimurium cases through the Swedish electronic notification system, and an outbreak strain was identified with whole genome sequencing. Overall, 109 cases with symptom onset between 17 September and 24 November 2022 were reported from 20 of 21 Swedish regions. The median age of cases was 52 years (range 4-87 years) and 62% were female. A case-control study found cases to be associated with consumption of rocket salad (adjusted odds ratio (aOR) = 4.9; 95% confidence interval (CI): 2.4-10, p value < 0.001) and bagged mixed salad (aOR = 4.0; 95% CI: 1.9-8.1, p value < 0.001). Trace-back, supported by Finnish authorities who identified the Swedish outbreak strain in a Finnish cluster during the same time period, identified rocket salad, cultivated, pre-washed and pre-packed in Sweden as the likely source of the outbreak. No microbiological analyses of rocket salad were performed. Our investigation indicates that bagged leafy greens such as rocket salad, regardless of pre-washing procedures in the production chain, may contain Salmonella and cause outbreaks, posing a health risk to consumers. We emphasise the need for primary producers of leafy greens to identify possible contamination points to prevent outbreaks.

COVID-19-associated mortality in individuals with serious mental disorders in Sweden during the first two years of the pandemic- a population-based register study.

BACKGROUND: Reports at the beginning of the COVID-19 pandemic suggested differences in COVID-19-associated mortality between individuals with serious mental disorders (SMD) and the population at large. AIM: To compare the pattern of COVID-19-associated mortality in individuals with and without SMD in Sweden over the two main pandemic years. METHODS: We compared the pattern of COVID-19-associated mortality in individuals with and without SMD in Sweden during 2020 and 2021. For SMD, we included psychotic disorder, bipolar disorder, and severe depression. The analysis was based on summary data from the Swedish Board of Health and Welfare covering the entire adult Swedish population. RESULTS: The overall relative risk (RR) for experiencing a COVID-19-associated death was 1.66 (CI 1.50-1.83; p < 0.001) for individuals with SMD versus individuals without SMD. The corresponding RRs were 3.25 (CI 2.84-3.71; p < 0.001) for individuals with psychotic disorder, 1.06 (CI 0.88-1.26; p = 0.54) for individuals with bipolar disorder, and 1.03 (CI 0.80-1.32; p = 0.80) for individuals with severe depression. Compared to their respective counterparts in the non-SMD group, in the psychotic disorder and severe depression group, the RR were higher in women than in men. In the bipolar disorder group, the RR was higher in men than in women. The RR of COVID-19-associated death was generally higher in younger individuals with SMD. Individuals with psychosis between 18 and 59 years had the highest RR of COVID-19-associated death with 7.25 (CI 4.54-11.59; p<0.001). CONCLUSIONS: Individuals with SMD, and particularly those with psychotic disorders, had a higher risk of COVID-19-associated death than the general population. As this is a pattern also seen with other infections, people with SMD may be similarly vulnerable in future pandemics.

Treatment Outcome of Severe Respiratory Type B Tularemia Using Fluoroquinolones.

BACKGROUND: Fluoroquinolones lack approval for treatment of tularemia but have been used extensively for milder illness. Here, we evaluated fluoroquinolones for severe illness. METHODS: In an observational study, we identified case-patients with respiratory tularemia from July to November 2010 in Jämtland County, Sweden. We defined severe tularemia by hospitalization for >24 hours and severe bacteremic tularemia by Francisella tularensis subsp. holarctica growth in blood or pleural fluid. Clinical data and drug dosing were retrieved from electronic medical records. Chest images were reexamined. We used Kaplan-Meier curves to evaluate time to defervescence and hospital discharge. RESULTS: Among 67 case-patients (median age, 66 years; 81% males) 30-day mortality was 1.5% (1 of 67). Among 33 hospitalized persons (median age, 71 years; 82% males), 23 had nonbacteremic and 10 had bacteremic severe tularemia. Subpleural round consolidations, mediastinal lymphadenopathy, and unilateral pleural fluid were common on chest computed tomography. Among 29 hospitalized persons with complete outcome data, ciprofloxacin/levofloxacin (n = 12), ciprofloxacin/levofloxacin combinations with doxycycline and/or gentamicin (n = 11), or doxycycline as the single drug (n = 6) was used for treatment. One disease relapse occurred with doxycycline treatment. Treatment responses were rapid, with median fever duration 41.0 hours in nonbacteremic and 115.0 hours in bacteremic tularemia. Increased age-adjusted Charlson comorbidity index predicted severe bacteremic tularemia (odds ratio, 2.7 per score-point; 95% confidence interval, 1.35-5.41). A 78-year-old male with comorbidities and delayed ciprofloxacin/gentamicin treatment died. CONCLUSIONS: Fluoroquinolone treatment is effective for severe tularemia. Subpleural round consolidations and mediastinal lymphadenopathy were typical findings on computed tomography among case-patients in this study.

Blood cultures with one venipuncture instead of two: a prospective clinical comparative single-center study including patients in the ICU, haematology, and infectious diseases departments.

OBJECTIVES: Blood culture is a key method for diagnosing bloodstream infections. In this prospective study, we aimed to investigate whether blood cultures collected with the one-puncture method results in fewer contaminants, i.e. microorganisms from the skin or the environment, and the same detection of relevant pathogens compared to the two-puncture method. Further, we aimed to investigate if the time to blood culture positivity could be useful in evaluating contaminants. METHODS: Patients planned for blood cultures were asked to participate in the study. From each recruited patient, six blood culture bottles were drawn, bottles 1-4 from the first venipuncture and bottles 5-6 from the second venipuncture. Within each patient, bottles 1-4 were compared to bottles 1, 2, 5, and 6 for contaminants and relevant pathogens. A sub-analysis was conducted on patients admitted to the ICU and those in the haematology department. We also assessed time-to-positivity for coagulase-negative staphylococci. RESULTS: In the final analysis, 337 episodes from 312 patients were included. Relevant pathogens were identified in 62/337 (18.4%) episodes in both methods. Contaminants were detected in 12 (3.6%) and 19 episodes (5.6%) using the one-puncture and two-puncture method (p = .039), respectively. Corresponding results were observed in the sub-analysis. Notably, relevant coagulase-negative staphylococci demonstrated a shorter time-to-positivity compared to contaminant coagulase-negative staphylococci. CONCLUSION: Blood cultures obtained using the one-puncture method resulted in significantly fewer contaminants and detected relevant pathogens equally to the two-puncture method. Time-to-positivity may be a useful additive indicator for predicting coagulase-negative staphylococci contamination in blood cultures.

Vaccine-induced correlate of protection against fatal COVID-19 in older and frail adults during waves of neutralization-resistant variants of concern: an observational study.

Background: To inform future preventive measures including repeated vaccinations, we have searched for a clinically useful immune correlate of protection against fatal COVID-19 among nursing homes residents. Methods: We performed repeated capillary blood sampling with analysis of S-binding IgG in an open cohort of nursing home residents in Sweden. We analyzed immunological and registry data from 16 September 2021 to 31 August 2022 with follow-up of deaths to 30 September 2022. The study period included implementation of the 3rd and 4th mRNA monovalent vaccine doses and Omicron virus waves. Findings: A total of 3012 nursing home residents with median age 86 were enrolled. The 3rd mRNA dose elicited a 99-fold relative increase of S-binding IgG in blood and corresponding increase of neutralizing antibodies. The 4th mRNA vaccine dose boosted levels 3.8-fold. Half-life of S-binding IgG was 72 days. A total 528 residents acquired their first SARS-CoV-2 infection after the 3rd or the 4th vaccine dose and the associated 30-day mortality was 9.1%. We found no indication that levels of vaccine-induced antibodies protected against infection with Omicron VOCs. In contrast, the risk of death was inversely correlated to levels of S-directed IgG below the 20th percentile. The death risk plateaued at population average above the lower 35th percentile of S-binding IgG. Interpretation: In the absence of neutralizing antibodies that protect from infection, quantification of S-binding IgG post vaccination may be useful to identify the most vulnerable for fatal COVID-19 among the oldest and frailest. This information is of importance for future strategies to protect vulnerable populations against neutralization resistant variants of concern. Funding: Swedish Research Council, SciLifeLab via Knut and Alice Wallenberg Foundation, VINNOVA. Swedish Healthcare Regions, and Erling Persson Foundation.

Persisting symptoms after Cryptosporidium hominis outbreak: a 10-year follow-up from Östersund, Sweden.

In late 2010, an outbreak of Cryptosporidium hominis affected 27,000 inhabitants (45%) of Östersund, Sweden. Previous research shows that abdomen and joint symptoms commonly persist up to 5 years post-infection. It is unknown whether Cryptosporidium is associated with sequelae for a longer duration, how persisting symptoms present over time, and whether sequelae are associated with prolonged infection. In this prospective cohort study, a randomly selected cohort in Östersund was surveyed about cryptosporidiosis symptoms in 2011 (response rate 69.2%). A case was defined as a respondent reporting new diarrhoea episodes during the outbreak. Follow-up questionnaires were sent after 5 and 10 years. Logistic regressions were used to examine associations between case status and symptoms reported after 10 years, with results presented as adjusted odds ratios (aOR) with 95% confidence intervals. Consistency of symptoms and associations with case status and number of days with symptoms during outbreak were analysed using X2 and Mann-Whitney U tests. The response rate after 10 years was 74% (n = 538). Case status was associated with reporting symptoms, with aOR of ~3 for abdominal symptoms and ~2 for joint symptoms. Cases were more likely to report consistent symptoms. Cases with consistent abdominal symptoms at follow-up reported 9.2 days with symptoms during the outbreak (SD 8.1), compared to 6.6 days (SD 6.1) for cases reporting varying or no symptoms (p = 0.003). We conclude that cryptosporidiosis was associated with an up to threefold risk for reporting symptoms 10 years post-infection. Consistent symptoms were associated with prolonged infection.

[Five cases of C. canimorsus during a short period of time at Östersund Hospital, Sweden]. / Fem fall av C canimorsus på kort tid vid Östersunds sjukhus.

We report a sudden increase in the number of cases of C. canimorsus bacteremia during 3 months in 2022 at Östersund Hospital, Sweden. Prior to these cases, the most recent one in the region occurred in 2015. Among the five cases, one suffered from meningitis and one was diagnosed as endocarditis. Dog contact was present in all cases, although dog bites could only be verified in two. Improved diagnostics could not be an explanation to the surge, since the analysis method for blood culture had been the same since 2015. No corresponding increase was noted nationally, according to the Public Health Agency of Sweden. The isolates have been included in the ongoing global study with the aim to explore Capnocytophaga in humans and animals using comparative genomics and genome wide association studies. The study is supported by several ESCMID (European Society of Clinical Microbiology and Infectious Diseases) study groups.

Increased incidence of late-onset inflammatory bowel disease and microscopic colitis after a Cryptosporidium hominis outbreak.

OBJECTIVES: In 2010, 27,000 inhabitants (45% of the population) of Östersund, Sweden, contracted clinical cryptosporidiosis after drinking water contaminated with Cryptosporidium hominis. After the outbreak, local physicians perceived that the incidence of inflammatory bowel disease (IBD), including ulcerative colitis (UC), Crohn's disease (CD), and IBD-unclassified, and microscopic colitis (MC) increased. This study assessed whether this perception was correct. MATERIALS AND METHODS: This observational study included adult patients (≥18 years old) from the local health care region who were diagnosed with pathology-confirmed IBD or MC during 2006-2019. We collected and validated the diagnosis, date of diagnosis, age at diagnosis, and sex from the Swedish quality register SWIBREG and electronic patient records. Population data were collected from Statistics Sweden. The incidences for 2006-2010 (pre-outbreak) and 2011-2019 (post-outbreak) were evaluated by negative binomial regression analysis and presented as incidence rate ratios (IRRs). Data were analyzed for IBD, for UC and CD separately, and MC. RESULTS: During the study period, we identified 410 patients with new onset IBD and 155 new cases of MC. Overall, we found a trend toward an increased incidence of IBD post-outbreak (IRR 1.39, confidence interval (CI) 0.99-1.94). In individuals ≥40 years old, the post-outbreak incidence significantly increased for IBD (IRR 1.69, CI 1.13-2.51) and CD (IRR 2.23, CI 1.08-4.62). Post-outbreak incidence of MC increased 6-fold in all age groups (IRR 6.43, CI 2.78-14.87). CONCLUSIONS: The incidence of late-onset IBD and MC increased after the Cryptosporidium outbreak. Cryptosporidiosis may be an environmental risk factor for IBD and MC.

Heterogeneity of Staphylococcus epidermidis in prosthetic joint infections: time to reevaluate microbiological criteria?

Prosthetic joint infection (PJI) is a feared and challenging to diagnose complication after arthroplasty, with Staphylococcus epidermidis as the major pathogen. One important criteria to define PJI is the detection of phenotypically indistinguishable microorganisms with identical antibiotic susceptibility pattern in at least two different samples. However, owing to phenotypical variation within genetic clones and clonal variation within a phenotype, the criteria may be ambiguous. We investigated the extent of diversity among coagulase-negative staphylococci (CoNS) in PJI and characterised S. epidermidis isolates from PJI samples, specifically multiple S. epidermidis isolates identified in individual PJI patients. We performed a retrospective cohort study on 62 consecutive patients with PJI caused by CoNS from two hospitals in Northern Sweden. In 16/62 (26%) PJIs, multiple S. epidermidis isolates were available for whole-genome analyses. Hospital-adapted multidrug-resistant genetic clones of S. epidermidis were identified in samples from 40/62 (65%) of the patients using a combination of pulsed-field gel electrophoresis and multilocus sequence typing. Whole-genome sequencing showed the presence of multiple sequence types (STs) in 7/16 (44%) PJIs where multiple S. epidermidis isolates were available. Within-patient phenotypical variation in the antibiotic susceptibility and/or whole-genome antibiotic resistance gene content was frequent (11/16, 69%) among isolates with the same ST. The results highlight the ambiguity of S. epidermidis phenotypic characterisation as a diagnostic method in PJI and call for larger systematic studies for determining the frequency of CoNS diversity in PJIs, the implications of such diversity for microbiological diagnostics, and the therapeutic outcomes in patients.

Increased Risks of Death and Hospitalization in Influenza/Pneumonia and Sepsis for Individuals Affected by Psychotic Disorders, Bipolar Disorders, and Single Manic Episodes: A Retrospective Cross-Sectional Study.

Individuals with severe mental disorders (SMDs) such as psychotic disorders, bipolar disorders, and single manic episodes have increased mortality associated with COVID-19 infection. We set up a population-based study to examine whether individuals with SMD also had a higher risk of hospitalization and death from other infectious conditions. Anonymized and summarized data from multiple Swedish patient registers covering the entire Swedish population were supplied by the Swedish National Board of Health and Welfare. The frequencies of hospitalizations and deaths associated with influenza/pneumonia and sepsis in individuals with SMD were compared with the rest of the population during 2018-2019. Possible contributing comorbidities were also examined, of which diabetes, cardiovascular disease, chronic lung disease, and hypertension were chosen. A total of 7,780,727 individuals were included in the study; 97,034 (1.2%) cases with SMD and 7,683,693 (98.8%) controls. Individuals with SMD had increased risk of death associated with influenza/pneumonia (OR = 2.06, 95% CI [1.87-2.27]) and sepsis (OR = 1.61, 95% CI [1.38-1.89]). They also had an increased risk of hospitalization associated with influenza/pneumonia (OR = 2.12, 95% CI [2.03-2.20]) and sepsis (OR = 1.89, 95% CI [1.75-2.03]). Our results identify a need for further evaluation of whether these individuals should be included in prioritized risk groups for vaccination against infectious diseases other than COVID-19.

Secretor Status is Associated with Susceptibility to Disease in a Large GII.6 Norovirus Foodborne Outbreak.

Norovirus is commonly associated with food and waterborne outbreaks. Genetic susceptibility to norovirus is largely dependent on presence of histo-blood group antigens (HBGA), specifically ABO, secretor, and Lewis phenotypes. The aim of the study was to determine the association between HBGAs to norovirus susceptibility during a large norovirus foodborne outbreak linked to genotype GII.6 in an office-based company in Stockholm, Sweden, 2015. A two-episode outbreak with symptoms of diarrhea and vomiting occurred in 2015. An online questionnaire was sent to all 1109 employees that had worked during the first outbreak episode. Food and water samples were collected from in-house restaurant and tested for bacterial and viral pathogens. In addition, fecal samples were collected from 8 employees that had diarrhea. To investigate genetic susceptibility during the outbreak, 98 saliva samples were analyzed for ABO, secretor, and Lewis phenotypes using ELISA. A total of 542 of 1109 (49%) employees reported gastrointestinal symptoms. All 8 fecal samples tested positive for GII norovirus, which was also detected in coleslaw collected from the in-house restaurant. Eating at the in-house restaurant was significantly associated with risk of symptom development. Nucleotide sequencing was successful for 5/8 fecal samples and all belonged to the GII.6 genotype. HBGA characterization showed a strong secretor association to norovirus-related symptoms (P = 0.014). No association between norovirus disease and ABO phenotypes was observed. The result of this study shows that non-secretors were significantly less likely to report symptoms in a large foodborne outbreak linked to the emerging GII.6 norovirus strain.

Death Associated With Coronavirus (COVID-19) Infection in Individuals With Severe Mental Disorders in Sweden During the Early Months of the Outbreak-An Exploratory Cross-Sectional Analysis of a Population-Based Register Study.

Background: Individuals with severe mental disorder (SMD) have a higher risk of somatic comorbidity and mortality than the rest of the population. We set up a population-based study to assess whether individuals with SMD had a higher risk of death associated with a COVID-19 infection (COVID-19 associated death) than individuals without SMD. Methods: Exploratory analysis with a cross-sectional design in the framework of a population-based register study covering the entire Swedish population. The Swedish Board for Health and Welfare (Socialstyrelsen) provided anonymized tabulated summary data for further analysis. We compared numbers of COVID-19 associated death in individuals with SMD (cases) and without SMD (controls). We calculated the odds ratio (OR) for the whole sample and by age group and four comorbidities, namely diabetes, cardiovascular disease, hypertension, chronic lung disease. Results: The sample comprised of 7,923,859 individuals, 103,999 with SMD and 7,819,860 controls. There were 130 (0.1%) COVID-19 associated deaths in the SMD group and 4,945 (0.06%) in the control group, corresponding to an OR of 1.98 (CI 1.66-2.35; p < 0.001). The odds were 4-fold for the age groups between 60 and 79 years and 1.5-fold for cardiovascular diseases. Individuals with SMD without any of the risk factors under study had 3-fold odds of COVID-19 associated death. Conclusion: Our preliminary results identify individuals with SMD as a further group at increased risk of COVID-19 associated death. In regard to comorbidities, future studies should explore the potential confounding or mediation role in the relationship between SMD and COVID-19 associated deaths.

Sick leave due to diarrhea caused by contamination of drinking water supply with Cryptosporidium hominis in Sweden: a retrospective study.

We investigated sick leave from work, studies, preschool, and kindergarten occurring between 1 November 2010 and 31 January 2011 and associated with a waterborne outbreak of diarrhea caused by Cryptosporidium hominis in late November 2010 in Östersund, Sweden with 45.2% of 60,000 residents being symptomatic. A questionnaire defining acute watery diarrhoea and/or ≥3 diarrhea episodes/day as cryptosporidiosis was sent to 1,508 residents in late January 2011 (response rate 69.2%). Among adults aged 18-60 years, 24.0% took sick leave for a mean of 4.6 (SD ± 4.0) days due to cryptosporidiosis, and an additional 10.6% were absent from work a mean of 4.0 (±2.2) days to care for symptomatic children. Among children (aged ≤17 years), 35.0% stayed home sick from kindergarten/preschool or school/university for a mean of 5.2 (±3.8) days resulting in 5.1 (±4.4) days of absence from work per sick child shared between parents/guardians. The estimated total number of sick leave days was 50,000 for adults and 20,700 for children, with an estimated direct cost of €7 million for employers. The potential impact on society of sick leave caused by waterborne diseases must be considered in decisions regarding the quality of drinking water.

Persisting post-infection symptoms 2 years after a large waterborne outbreak of Cryptosporidium hominis in northern Sweden.

OBJECTIVES: In 2010-2011, a large waterborne outbreak of Cryptosporidium hominis affected the city of Östersund in Sweden. Previous findings had suggested that gastrointestinal symptoms can persist for up to 11 months after the initial infection. Here we investigated whether the parasite could cause sequelae in infected individuals up to 28 months after the outbreak. We compared cases linked to the outbreak and the previous follow-up study with non-cases regarding symptoms present up to 28 months after the initial infection. We investigated whether cases were more likely to report a list of symptoms at follow-up compared to non-cases, calculating odds ratio and 95% confidence interval obtained through logistic regression. RESULTS: A total of 559 individuals (215 cases) were included in the study. Forty-eight percent of the outbreak cases reported symptoms at follow-up. Compared to non-cases, cases were more likely to report watery diarrhea, diarrhea, abdominal pain, fatigue, nausea, headache, or joint stiffness/pain/discomfort at follow-up after adjusting for age and sex. Our findings suggest that gastrointestinal symptoms and joint pain can persist several years after the initial Cryptosporidium infection and should be regarded as a potential cause of unexplained gastrointestinal symptoms or joint pain in people who have had this infection.

Significant spread of extensively drug-resistant Acinetobacter baumannii genotypes of clonal complex 92 among intensive care unit patients in a university hospital in southern Iran.

PURPOSE: Infections associated with Acinetobacter baumannii represent an increasing threat in healthcare settings. Therefore, we investigated the epidemiological relationship between clinical isolates of A. baumannii obtained from patients in a university hospital in Bandar Abbas in southern Iran. METHODOLOGY: Sixty-four consecutive non-duplicate clinical isolates collected during 2014-2015 were subjected to susceptibility testing, clonal relationship analysis using PFGE, multilocus variable-number tandem-repeat analysis (MLVA) and multilocus sequence typing (MLST), and examined for the presence of carbapenemases and integrons. RESULTS: Almost all A. baumannii isolates were extensively drug-resistant (XDR; 98 %) and carried an OXA carbapenemase gene (blaOXA-23-like; 98 %) and class 1 integrons (48 %). PFGE and MLST analysis identified three major genotypes, all belonging to clonal complex 92 (CC92): sequence type 848 (ST848) (n=23), ST451 (n=16) and ST195 (n=8). CC92 has previously been documented in the hospital setting in northern Iran, and ST195 has been reported in Arab States of the Persian Gulf. These data suggest national and global transmission of A. baumannii CC92. CONCLUSION: This report demonstrates the occurrence and potential spread of closely related XDR genotypes of A. baumannii CC92 within a university hospital in southern Iran. These genotypes were found in the majority of the investigated isolates, showed high prevalence of blaOXA-23 and integron class 1, and were associated with stay in the intensive care unit. Very few treatment options remain for healthcare-adapted XDR A. baumannii, and hence effective measures are desperately needed to reduce the spread of these strains and resultant infections in the healthcare setting.

Symptoms and risk factors of Cryptosporidium hominis infection in children: data from a large waterborne outbreak in Sweden.

Cryptosporidium is a major cause of diarrheal disease worldwide. In developing countries, this infection is endemic and in children, associated with growth faltering and cognitive function deficits, with the most severe impact on those aged <2 years. Little has been reported about symptoms and risk factors for children in industrialized countries, although the disease incidence is increasing in such regions. In November 2010, a large waterborne outbreak of C. hominis occurred in the city of Östersund in Sweden. Approximately 27,000 of the 60,000 inhabitants were symptomatic. We aimed to describe duration of symptoms and the risk factors for infection with C. hominis in children aged <15 years in a Western setting. Within 2 months after a boil water advisory, a questionnaire was sent to randomly selected inhabitants of all ages, including 753 children aged <15 years. Those with ≥3 loose stools/day were defined as cases of diarrhoea. The response rate was 70.3%, and 211 children (39.9%) fulfilled the case definition. Mean duration of diarrhoea was 7.5 days (median 6, range 1-80 days). Recurrence, defined as a new episode of diarrhoea after ≥2 days of normal stools, occurred in 52.5% of the cases. Significant risk factors for infection, besides living within the distribution area of the contaminated water plant, included a high level of water consumption, male sex, and a previous history of loose stools. The outbreak was characterized by high attack and recurrence rates, emphasizing the necessity of water surveillance to prevent future outbreaks.

Colonization of patients, healthcare workers, and the environment with healthcare-associated Staphylococcus epidermidis genotypes in an intensive care unit: a prospective observational cohort study.

BACKGROUND: During the last decades, healthcare-associated genotypes of methicillin-resistant Staphylococcus epidermidis (HA-MRSE) have been established as important opportunistic pathogens. However, data on potential reservoirs on HA-MRSE is limited. The aim of the present study was to investigate the dynamics and to which extent HA-MRSE genotypes colonize patients, healthcare workers (HCWs) and the environment in an intensive care unit (ICU). METHODS: Over 12 months in 2006-2007, swab samples were obtained from patients admitted directly from the community to the ICU and patients transferred from a referral hospital, as well as from HCWs, and the ICU environment. Patients were sampled every third day during hospitalization. Antibiotic susceptibility testing was performed according to EUCAST guidelines. Pulsed-field gel electrophoresis and multilocus sequence typing were used to determine the genetic relatedness of a subset of MRSE isolates. RESULTS: We identified 620 MRSE isolates from 570 cultures obtained from 37 HCWs, 14 patients, and 14 environmental surfaces in the ICU. HA-MRSE genotypes were identified at admission in only one of the nine patients admitted directly from the community, of which the majority subsequently were colonized by HA-MRSE genotypes within 3 days during hospitalization. Almost all (89%) of HCWs were nasal carriers of HA-MRSE genotypes. Similarly, a significant proportion of patients transferred from the referral hospital and fomites in the ICU were widely colonized with HA-MRSE genotypes. CONCLUSIONS: Patients transferred from a referral hospital, HCWs, and the hospital environment serve as important reservoirs for HA-MRSE. These observations highlight the need for implementation of effective infection prevention and control measures aiming at reducing HA-MRSE transmission in the healthcare setting.

Outbreak of Neisseria meningitidis capsular group W among scouts returning from the World Scout Jamboree, Japan, 2015.

The 23rd World Scout Jamboree was held in Japan from 28 July to 8 August 2015 and was attended by over 33,000 scouts from 162 countries. An outbreak of invasive meningococcal disease capsular group W was investigated among participants, with four confirmed cases identified in Scotland, who were all associated with one particular scout unit, and two confirmed cases in Sweden; molecular testing showed the same strain to be responsible for illness in both countries. The report describes the public health action taken to prevent further cases and the different decisions reached with respect to how wide to extend the offer of chemoprophylaxis in the two countries; in Scotland, chemoprophylaxis was offered to the unit of 40 participants to which the four cases belonged and to other close contacts of cases, while in Sweden chemoprophylaxis was offered to all those returning from the Jamboree. The report also describes the international collaboration and communication required to investigate and manage such multinational outbreaks in a timely manner.