The pneumococcal conjugate vaccine had a sustained effect on Swedish children 8 years after its introduction.

AIM: The pneumococcal conjugate vaccine, which covered seven serotypes of Streptococcus pneumoniae (PCV7), was introduced in Stockholm, Sweden, in 2007. It was replaced by a 13-valent vaccine (PCV13) in 2011. We previously reported a decreased incidence of pneumonia and sinusitis among young children 4 years after the introduction of the PCV7. This study followed the incidence of pneumonia, sinusitis, mastoiditis and meningitis for four more years. METHODS: We studied validated hospital registry data covering children up to 17 years of age, who were hospitalised in the Stockholm region from 2003 to 2016, when the child population peaked at 485 687. All 11 115 cases diagnosed with pneumonia, coded as bacterial pneumonia, sinusitis, mastoiditis, bacterial meningitis or empyema, were identified. The controls had viral pneumonia or pyelonephritis. RESULTS: The incidence rates for children under 2 years of age hospitalised for sinusitis, mastoiditis and meningitis decreased significantly by 61%-79% during the eight-year post-vaccination period. Hospitalisations for bacterial pneumonia decreased by 19%-25% in the same age group. These changes were probably due to both the vaccines and changes in diagnosis routines. CONCLUSION: The effect of vaccination on children under 2 years of age was sustained 8 years after the introduction of the pneumococcal conjugate vaccines.

Pre-admission virus detection during the COVID-19 pandemic in children with and without symptoms of infection.

AIM: Pre-admission viral screening is used only in exceptional situations such as pandemics. We therefore evaluated pre-admission screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), respiratory syncytial virus (RSV) and influenza during the COVID-19 pandemic, comparing epidemiology and clinical features of admitted children. METHODS: Children were screened at a paediatric emergency department from 1 March 2020 to 30 June 2022 by nasopharyngeal sampling and polymerase chain reaction kit. We retrospectively retrieved positive results from the laboratory and scrutinised charts of admitted children. RESULTS: Out of 15 927 screened children, 522, 127 and 572 were positive and admitted with RSV, influenza A or SARS-CoV-2, respectively. Of these, 29 (5.6%), 26 (24.1%) and 245 (44.8%) were incidental findings, lacking symptoms of infection. RSV and influenza A were initially absent but re-emerged in the autumn of 2021. The rate of COVID-19 rose when the Omicron variant emerged in December 2021. The median age of children with RSV was 0.3 years, of those with influenza A 6.7 years and of those with COVID-19 1.6 years. Major complications were rare. CONCLUSION: Frequent incidental detections of SARS-CoV-2 likely reflected widespread presence of a mild infection. Clinically, COVID-19 was like other viral respiratory infections in children.

Human bocavirus 1 epidemiology in children in relation to virus load and codetection.

AIM: Human bocavirus 1 (HBoV1) has been associated with respiratory tract infections in children. We aimed at retrospectively describing patient characteristics, seasonality, pre-existing medical conditions, codetections, clinical manifestations and complications of HBoV1 infection in relation to viral load in the child population in Stockholm, with the overarching aim of elucidating the clinical significance of HBoV1. METHODS: We included all hospitalised children 0-17 years testing positive for HBoV1 by real-time polymerase chain reaction on nasopharyngeal aspirates 1 July 2008-30 June 2019. Patients with HBoV1 single detection, high viral load expressed as an HBoV1-DNA cycle threshold (Ct) < 25, or both, were separately analysed. We retrieved information on pre-existing conditions and clinical course from the medical records. RESULTS: We found 768 episodes in 727 children, 496 (64.6%) male and 441 (60.7%) previously healthy. The median age was 17.6 months. Most (476/768, 62.0%) episodes occurred during December-March. HBoV1 was in 549 episodes (71.5%) codetected with other viruses. Ct < 25 was independently associated with young age, single detection of HBoV1 and presentation early in the epidemic season. We saw few differences in clinical manifestations between the subgroups. CONCLUSION: Our findings are consistent with primary HBoV1 infection causing mild-to-severe respiratory tract manifestations in young children.

Chronic Urticaria: A Swedish Registry-based Cohort Study on Population, Comorbidities and Treatment Characteristics.

Swedish databases present unique opportunities to research population data on diseases and treatments. The current study is, to our knowledge, the most comprehensive registry-based study on a chronic urticaria population in Sweden to date. The aim of this study was to describe the chronic urticaria population in Stockholm County regarding epidemiology, demographics, comorbidity, healthcare usage and treatment patterns in relation to current international guidelines. Real-world data were extracted between 2013 and 2019, yielding 10,642 adult patients. Study period prevalence of chronic urticaria was 0.53%, the mean annual incidence was approximately 0.08%, and 68% of patients were female. Regarding diagnosis, 58% were first diagnosed in primary care, approximately 50% were diagnosed before the age of 40 years. Regarding type of urticaria, 89% had chronic spontaneous urticaria, 11% had chronic inducible urticaria, and 5% of patients with chronic urticaria had coexisting angioedema. Common coexisting diagnoses were, for example, asthma, allergy, psychiatric and behavioural disorders and cardiometabolic disorders. Treatment patterns generally followed guidelines, yet data indicated that guidelines were not fully implemented, especially in primary care.

Acute infection as cause of hospitalization of asylum-seeking children and adolescents in Stockholm, Sweden 2015-2016.

We aimed to identify hospitalizations due to infectious diseases among asylum seekers and compare them to those of the resident population 1.6.2015-31.10.2016. Administrative numbers assigned to hospitalized non-resident children made them identifiable in the discharge register. The examined populations, expressed as person-years, were 334,573 residents and 7565 asylum seekers. There were 2500 episodes of infectious disease in 2240 resident children and 139 episodes in 121 asylum seekers. Among prevalent infections contracted before or during migration, there were 33 cases of tuberculosis, four of malaria, and one of louse-borne relapsing fever, all of which occurred in 13-17-year-old unaccompanied minors. Among younger asylum seekers, there were no significant differences in the spectrum of infectious discharge diagnoses compared to residents, but across all incident infections, 0-6-year-old asylum seekers had 3.2-fold and 7-12-year-old a 4.7-fold greater risk of being admitted. Screening for multidrug-resistant bacteria showed that 45/160 (28%) of the asylum seekers were colonized, but clinical infections caused by these species were rare.Conclusion: There was a high rate of hospitalizations for acute infectious diseases in asylum-seeking children, but the spectrum and severity of infections were similar to that in resident children. What is known: • Mental and physical health problems are common in immigrant children and adolescents. What is new: • Hospitalizations due to acute infections in asylum-seeking children and adolescents are common. In the context of this study, the severity and spectrum of infectious diseases seemed to be the same in the two groups; the increased hospitalization rate in asylum seekers may be due to social factors and perceived need for more support.

Children hospitalised with four common viral diseases showed epidemiological differences but few socio-economic variations.

AIM: This study explored the differences in demographic and socio-economic factors between children hospitalised due to four common viral infections. METHODS: Demographic data were obtained from Statistics Sweden on >3000 children admitted to Astrid Lindgren Children's Hospital in 2009-2014 with rotavirus, influenza, respiratory syncytial virus (RSV) or chickenpox. We compared demographic and socio-economic factors between case groups using logistic regression with rotavirus cases as reference. RESULTS: There were differences in the median age at admission; RSV cases were younger (0.4 years), influenza (2.4 years) and chickenpox cases (2.7 years) older than rotavirus cases (1.2 years). RSV, influenza and chickenpox cases lived in families with more children than rotavirus cases. RSV and influenza cases were more likely to have underlying chronic conditions. Mothers of RSV cases were more likely to be born in Sweden. Further socio-economic differences were not robustly confirmed in sensitivity analyses. CONCLUSION: We found a few differences in demographic factors between children hospitalised with the four common infections, which were mainly explained by the epidemiology and transmission patterns of these infections.

Rates and risk factors of severe respiratory syncytial virus infection in 2008-2016 compared with 1986-1998.

AIM: Since the introduction in 1979 of rapid testing using immunofluorescence, we have collected information about children hospitalised for confirmed respiratory syncytial virus (RSV) infection in the northern Stockholm area. We here report hospitalisation rates, risk factors and complications in 2008-2016 compared with 1986-1998. METHODS: Microbiological laboratory reports and retrospective chart review. Comparison of the two periods was complicated by changing testing routines, with a more sensitive method and increased testing of older children in the late period. RESULTS: In infants, there was an 12.3% increase in the population-based rate of hospital admission for RSV infection from 12.2 to 13.7/1000. Including all children <5 years, there was a 48% increase from 2.7 to 4.0/1000. The median length of stay remained unchanged at 3 days. The need of intensive care decreased in healthy infants but remained high in older children with comorbidity. CONCLUSION: Considering the changed diagnosis routines, we believe that the rate of hospital admission of infants for RSV infection was unchanged throughout the observed years. The increased rates of older children with confirmed RSV likely resulted from increased testing of children with risk factors for a complicated course.

Foreign background and older age of children were associated with infection in Swedish tuberculosis contacts.

AIM: We present our results using interferon-gamma release assays in any child <18 years or tuberculin skin tests in Bacille Calmette-Guérin unvaccinated children for tuberculosis contact investigation in Stockholm, Sweden. METHODS: During 2000-2019, we investigated 892 children with a median age of seven years. We explored associations between TB infection and characteristics such as closeness to contact, age, sex, BCG status and foreign origin. RESULTS: The overall rates were for TB infection 10.2% (n = 91) and for TB disease 1.1% (n = 10). In addition to infectiousness of index case and closeness of contact, foreign background, male sex and increasing age were independently associated with infection. In foreign-born children, the rates of tuberculosis infection and disease were 18.7% and 3.9%, respectively. In 18/46 (39%) infected foreign-born children, a baseline negative tuberculosis test supported a diagnosis of recent infection. CONCLUSION: Foreign background, older age and male sex were associated with infection. In a significant proportion of infected children, a previous negative test made recent infection likely.

A 10-year retrospective survey of acute childhood osteomyelitis in Stockholm, Sweden.

AIM: Children with osteomyelitis present with a range of signs and symptoms and with varying degree of severity. The purpose of this study was to provide data on a population-based 10-year material of children with acute osteomyelitis. METHODS: All children, 0-14 years in Stockholm Region with acute osteomyelitis hospitalised in July 2005-June 2015, were retrospectively studied. Time to hospital presentation, disease localization, inflammation markers, imaging procedures, microbiology, severity classified by the presence of complications, surgical procedures, hospital length of stay and seasonal variation were recorded. RESULTS: There were 430 children with acute osteomyelitis; 61% were boys. The incidence per 100 000 person-years was 11.6; 9.3 in girls and 13.1 in boys. Median age at admission was 2.9 years with no peak later in childhood. Median time from first symptom to diagnosis was 4 days (range 1-21) and 48% of the cases were localised to femur or tibia. Mean C-reactive protein was 59 mg/L (range 1-376). Blood (n = 82) or tissue cultures (n = 54) were positive in 118 (28%) children. The most common pathogen was Staphylococcus aureus (n = 88) followed by Streptococcus pyogenes (n = 12). Surgery was performed in 71 children (17%). There was no mortality. Severe complications were seen in 14 (3.3%) children, five of whom were admitted to intensive care. Median hospital length of stay was 4 days (range 1-60). CONCLUSIONS: Osteomyelitis in children is a diagnostic challenge with a low yield of positive bacterial cultures. Few children with uncomplicated disease need surgery, but the risk of severe complications is not negligible.

Urinary PGE2 metabolite levels in hospitalised infants with infections compared to age-matched controls.

AIM: To determine the urinary tetranor-prostaglandin E2 metabolite in healthy infants and in hospitalised infants with upper and lower respiratory tract as well as gastrointestinal infections. METHODS: A prospective cross-sectional study to determine baseline concentrations of urinary tetranor-prostaglandin E2 metabolite was conducted in 81 healthy infants aged one week to one year and in 142 hospitalised infants with infections. Prostaglandin metabolite levels were measured by liquid chromatography tandem mass spectrometry. RESULTS: In healthy infants, urinary prostaglandin E2 metabolite levels decreased with age and did not differ between girls and boys. Infections of the lower respiratory (n = 78) and gastrointestinal tract (n = 12) correlated with increased levels of the prostaglandin E2 metabolite. In contrast, infants hospitalised with upper respiratory tract infections (n = 23) exhibited similar levels as healthy, age-matched controls. Lower prostaglandin E2 levels were found after treatment with acetaminophen in hospitalised children. Prostaglandin E2 metabolite levels did not correlate with length of hospitalisation or need for respiratory support. CONCLUSION: This study first provides normal levels of urinary prostaglandin E2 metabolite in infants and secondly demonstrates elevated levels in hospitalised children with lower respiratory tract and gastrointestinal infections.

The impact of pneumococcal conjugate vaccine on community-acquired pneumonia hospitalizations in children with comorbidity.

The burden of community-acquired pneumonia (CAP) in high-income countries is still significant. The introduction of pneumococcal conjugate vaccines (PCV) has reduced the overall need for hospitalization for CAP. However, it is not clear whether children with underlying disease also have benefitted from the PCV immunization programme. Children 0 to <5 years of age hospitalized with CAP and discharged with an ICD-10 code of J13-J18.9 between November 1, 2005, and April 30, 2007 (pre-vaccination period), and November 1, 2010, and April 30, 2012 (post-vaccination period), were eligible for this study. Data on hospitalization and discharge diagnoses were retrieved from the Hospital Registry. In addition, chart review was performed in 50% of the patients. Our result confirmed a decrease in hospitalization rate for CAP in the PCV13 period. Chart review revealed that half of the patients had underlying comorbidity and these children had more severe symptoms and required longer hospital stay. Intensive care was provided to less than 10% of the children and mostly for children with an underlying neurological disease. CONCLUSIONS: We show that all children have benefitted from the reduction of CAP hospitalization after introduction of PCV. Our finding emphasizes the importance of children with chronic diseases receiving adequate vaccinations that may protect from lower respiratory diseases. What is known? • Community-acquired pneumonia is a leading infectious cause of hospitalizations and death among children <5 years of age globally • Pneumococcal conjugate vaccine reduces the hospitalizations of all-cause pneumonia What is new? • We show that also children with underlying comorbidities have benefitted from PCV immunization with a reduction of CAP hospitalization • We show that approximately half of all children hospitalized with CAP also have underlying comorbidities.

Changing diagnosis coding routines may confound the results of longitudinal childhood pneumonia studies.

AIM: This Swedish study compared the discharge diagnosis codes used for children up to the age of five hospitalised for acute lower respiratory tract infections before and after the introduction of the pneumococcal conjugate vaccine in 2007. METHODS: The International Classification of Diseases-10th revision codes were used. We compared the discharge diagnosis codes at the Astrid Lindgren Children's Hospital from 1 July 2005 to 30 June 2007 (n=1,127) and 1 July 2011 to 30 June 2013 (n=1,240) in relation to the diagnostic methods used. RESULTS: There was a 54% reduction in the rate of all-cause pneumonia from the first to the second period in children aged 0-1 years, but some of this could have been due to the improved diagnosis of viral infections and us changing the code for respiratory syncytial virus infection from pneumonia to bronchiolitis. The overall rate of acute lower respiratory tract infections was unchanged. CONCLUSION: We could not determine how much of the reduction in bacterial pneumonia in children under one was because of the introduction of the pneumococcal conjugate vaccine, based solely on discharge codes. Longitudinal register studies should take changes in diagnosis codes into account.

Review of the aetiology, diagnostics and outcomes of childhood encephalitis from 1970 to 2009.

AIM: Encephalitis is a rare, serious condition, and antiviral therapies, increased knowledge of inflammatory pathways and improved diagnostics have increased the therapeutic possibilities. We describe 40 years of childhood encephalitis in Sweden, covering the diagnostics, aetiology and outcomes. METHODS: We reviewed the clinical data that were available for all children discharged from the Karolinska University Hospital in Stockholm following treatment for encephalitis from 1970 to 2009. The hospital treated all children in the region with the condition during the study period. RESULTS: There were 408 episodes of encephalitis from 1970 to 2009 and the incidence was similar over the whole period, ranging from 6.4 to 8.7 per 100 000 child years. Although mortality markedly decreased from 10% in the first decade to zero in the last decade, and aetiologies shifted, no clear long-term improvements in outcome were seen. The need for intensive care was unchanged (18-20%) for each of the study intervals, possibly indicating that the severity of cases remained unaltered. CONCLUSION: Understanding the pathophysiological mechanisms of encephalitis is vitally important for developing more efficient treatment regimens. As well as reporting the results of this 40-year study, this study considers possible explanations, addresses current therapeutic options and explores directions for central nervous system infection research.

It's About Me: Patients' Experiences of Patient Participation in the Web Behavior Change Program for Activity in Combination With Multimodal Pain Rehabilitation.

BACKGROUND: Patients' participation in their health care is recognized as a key component in high-quality health care. Persons with persistent pain are recommended treatments with a cognitive approach from a biopsychosocial explanation of pain, in which a patient's active participation in their rehabilitation is in focus. Web-based interventions for pain management have the potential to increase patient participation by enabling persons to play a more active role in rehabilitation. However, little is known about patients' experiences of patient participation in Web-based interventions in clinical practice. OBJECTIVE: The objective of our study was to explore patients' experiences of patient participation in a Web Behavior Change Program for Activity (Web-BCPA) in combination with multimodal rehabilitation (MMR) among patients with persistent pain in primary health care. METHODS: Qualitative interviews were conducted with 15 women and 4 men, with a mean age of 45 years. Data were analyzed with qualitative content analysis. RESULTS: One theme, "It's about me," and 4 categories, "Take part in a flexible framework of own priority," "Acquire knowledge and insights," "Ways toward change," and "Personal and environmental conditions influencing participation," were developed. Patient participation was depicted as being confirmed in an individualized and structured rehabilitation framework of one's own choice. Being confirmed was fundamental to patient participation in the interaction with the Web-BCPA and with the health care professionals in MMR. To acquire knowledge and insights about pain and their life situation, through self-reflection in the solitary work in the Web-BCPA and through feedback from the health care professionals in MMR, was experienced as patient participation by the participants. Patient participation was described as structured ways to reach their goals of behavior change, which included analyzing resources and restrictions, problem solving, and evaluation. The individual's emotional and cognitive resources and restrictions, as well as health care professionals and significant others' attitudes and behavior influenced patient participation in the rehabilitation. To some extent there were experiences of restrained patient participation through the great content of the Web-BCPA. CONCLUSIONS: Patient participation was satisfactory in the Web-BCPA in combination with MMR. The combined treatment was experienced to increase patient participation in the rehabilitation. Being confirmed through self-identification and finding the content of the Web-BCPA trustworthy was emphasized. Patient participation was experienced as a learning process leading to new knowledge and insights. Higher user control regarding the timing of the Web-BCPA and therapist guidance of the content may further increase patient participation in the combined treatment.

Paediatric tuberculosis cases increased in Stockholm from 1971 to 2015 following the rising number of children with immigrant backgrounds.

AIM: This study described the epidemiology and clinical features of childhood tuberculosis (TB) in Stockholm over a 45-year period, when there was a resurge of tuberculosis concomitant with increased immigration. METHODS: We describe 220 children up to the age of 16 years with active TB, seen at the Astrid Lindgren Children's Hospital from 1971 to 2015. The study period was divided into three 15-year periods. RESULTS: Cases increased from ten children in 1971-1985 to 76 in 1986-2000 and 134 in 2001-2015, with overall incidence increasing from <1 to four per 100 000. From 2001 to 2015, 79% of cases, or at least one parent, were born in high-incidence countries. The incidence in this group was 35 per 100 000, but remained at 0.9 per 100 000 in other children. After 2000, most cases were detected by active contact tracing and immigrant screening. The most common manifestation was from the lungs. Meningitis and miliary tuberculosis were found in 7%, with two deaths. Antimicrobial resistance was an increasing problem. CONCLUSION: The increasing incidence of TB in Stockholm was largely limited to children with a background in high-incidence countries. Most children today have subclinical forms of TB. Although preventive measures are effective, severe cases still occur, especially among adolescent immigrants.

Effects of the Web Behavior Change Program for Activity and Multimodal Pain Rehabilitation: Randomized Controlled Trial.

BACKGROUND: Web-based interventions with a focus on behavior change have been used for pain management, but studies of Web-based interventions integrated in clinical practice are lacking. To emphasize the development of cognitive skills and behavior, and to increase activity and self-care in rehabilitation, the Web Behavior Change Program for Activity (Web-BCPA) was developed and added to multimodal pain rehabilitation (MMR). OBJECTIVE: The objective of our study was to evaluate the effects of MMR in combination with the Web-BCPA compared with MMR among persons with persistent musculoskeletal pain in primary health care on pain intensity, self-efficacy, and copying, as part of a larger collection of data. Web-BCPA adherence and feasibility, as well as treatment satisfaction, were also investigated. METHODS: A total of 109 participants, mean age 43 (SD 11) years, with persistent pain in the back, neck, shoulder, and/or generalized pain were recruited to a randomized controlled trial with two intervention arms: (1) MMR+WEB (n=60) and (2) MMR (n=49). Participants in the MMR+WEB group self-guided through the eight modules of the Web-BCPA: pain, activity, behavior, stress and thoughts, sleep and negative thoughts, communication and self-esteem, solutions, and maintenance and progress. Data were collected with a questionnaire at baseline and at 4 and 12 months. Outcome measures were pain intensity (Visual Analog Scale), self-efficacy to control pain and to control other symptoms (Arthritis Self-Efficacy Scale), general self-efficacy (General Self-Efficacy Scale), and coping (two-item Coping Strategies Questionnaire; CSQ). Web-BCPA adherence was measured as minutes spent in the program. Satisfaction and Web-BCPA feasibility were assessed by a set of items. RESULTS: Of 109 participants, 99 received the allocated intervention (MMR+WEB: n=55; MMR: n=44); 88 of 99 (82%) completed the baseline and follow-up questionnaires. Intention-to-treat analyses were performed with a sample size of 99. The MMR+WEB intervention was effective over time (time*group) compared to MMR for the two-item CSQ catastrophizing subscale (P=.003), with an effect size of 0.61 (Cohen d) at 12 months. There were no significant between-group differences over time (time*group) regarding pain intensity, self-efficacy (pain, other symptoms, and general), or regarding six subscales of the two-item CSQ. Improvements over time (time) for the whole study group were found regarding mean (P<.001) and maximum (P=.002) pain intensity. The mean time spent in the Web-based program was 304 minutes (range 0-1142). Participants rated the items of Web-BCPA feasibility between 68/100 and 90/100. Participants in the MMR+WEB group were more satisfied with their MMR at 4 months (P<.001) and at 12 months (P=.003). CONCLUSIONS: Adding a self-guided Web-based intervention with a focus on behavioral change for activity to MMR can reduce catastrophizing and increase satisfaction with MMR. Patients in MMR may need more supportive coaching to increase adherence in the Web-BCPA to find it valuable. CLINICALTRIAL: Clinicaltrials.gov NCT01475591; https://clinicaltrials.gov/ct2/show/NCT01475591 (Archived by WebCite at http://www.webcitation.org/6kUnt7VQh).

The aetiology of paediatric bloodstream infections changes after pneumococcal vaccination and group B streptococcus prophylaxis.

AIM: This study explored the incidence and aetiology of bloodstream infections after patients received the pneumococcal conjugate vaccination and a risk-based intrapartum antibiotic prophylaxis against early onset sepsis caused by group B streptococcus. We also monitored clinically relevant antimicrobial resistance. METHOD: We studied 3986 positive blood cultures from children up to 17 years of age at a paediatric hospital in Stockholm, Sweden, using data from medical records before and after the initiatives, to reduce early onset sepsis, were introduced in 2007 and 2008. RESULTS: Bloodstream infections caused by Streptococcus pneumoniae declined by 42% overall (5.6 to 3.2/100 000) and by 62% in previously healthy children under 36 months of age (24.2 to 9.2/100 000). Early onset sepsis caused by group B streptococcus declined by 60% (0.5 to 0.2/1000 live born children). Bacterial meningitis caused by these bacteria decreased by 70%. Staphylococcus aureus and various Gram-negative bacteria became the dominant pathogens, in both previously healthy children and those with underlying disease. Overall, antimicrobial resistance remained low between the two 5-year study periods. CONCLUSION: Pneumococcal conjugate vaccination and risk-based intrapartum antibiotic prophylaxis against group B streptococcus effectively decreased the incidence of bloodstream infections. Empirical antibiotic therapy should target Staphylococcus aureus in both community and hospital-acquired invasive bacterial infections.

Clinical manifestations of invasive pneumococcal disease by vaccine and non-vaccine types.

Pneumococcal conjugated vaccines (PCVs) have shown protection against invasive pneumococcal disease by vaccine serotypes, but an increase in non-vaccine serotype disease has been observed. Type-specific effects on clinical manifestation need to be explored. Clinical data from 2096 adults and 192 children with invasive pneumococcal disease were correlated to pneumococcal molecular serotypes. Invasive disease potential for pneumococcal serotypes were calculated using 165 invasive and 550 carriage isolates from children. The invasive disease potential was lower for non-PCV13 compared to vaccine-type strains. Patients infected with non-PCV13 strains had more underlying diseases, were less likely to have pneumonia and, in adults, tended to have a higher mortality. Furthermore, patients infected with pneumococci belonging to clonal serotypes only expressing non-PCV13 capsules had a higher risk for septicaemia and mortality. PCV vaccination will probably lead to a decrease in invasive pneumococcal disease but an alteration in the clinical manifestation of invasive pneumococcal disease. Genetic lineages causing invasive pneumococcal disease in adults often express non-vaccine serotypes, which can expand after vaccination with an increased risk of infection in patients with underlying diseases.

Burden of severe rotavirus disease leading to hospitalization assessed in a prospective cohort study in Sweden.

BACKGROUND: The aim of this prospective cohort study was to estimate the burden of severe disease caused by rotavirus-induced gastroenteritis in Swedish children aged < 5 y. METHODS: Rotavirus-positive children admitted to hospitals serving 3 geographical regions with 155,838 children aged < 5 y, were offered inclusion in this 1-year study. Rotavirus strains identified were genotyped using multiplex PCR. Disease progression was documented through interviews and chart reviews. RESULTS: In total, 604 children with rotavirus-induced gastroenteritis were included in the study. Forty-nine of 604 (8.1%) fulfilled the criteria for nosocomial infection. The minimum incidence was 388 per 100,000, with significant variability between study regions, ranging from 280 to 542 per 100,000. In all regions, the peak season occurred in February-April, but the season start varied, with first cases observed in October in the eastern region and December in the northern region. Genotypes identified differed between the regions: G1[P8] was most prevalent in all regions (77%), while the most varied pattern was observed in the western region, with G1[P8] observed in 61%, G4[P8] in 13%, G9[P8] in 10%, G2[P4] in 8%, and G3[P8] in 8% of the children. The median age of hospitalized children was 14 months and the median total duration of diarrhoea was 6.9 days. Sixty-eight percent reported a temperature > 38.5°C upon admission. Complications occurred in > 10% of the children, with hypertonic dehydration (32/604) and seizures (10/604) occurring most frequently. CONCLUSIONS: Rotaviruses may cause severe febrile acute gastroenteritis leading to dehydration requiring acute rehydration in hospital. In addition, further complications occurred in > 10% of hospitalized children.

Children with multiple viral respiratory infections are older than those with single viruses.

AIM: To study the clinical impact of multiple viral respiratory infections compared to single infections. METHODS: Demographic data from 37 multiple infection periods in children <5 years of age were compared to data from 193 episodes with single infections. Clinical data derived from patient records of the multiple infection episodes were further compared to data from 93 matched control episodes with single infections. RESULTS: The mean age of patients with multiple viral findings was 12.7 months, compared to 5.7 months for those with single findings (p < 0.01). Wheezing was the most common diagnosis in both groups, except among children who were only infected with the coronavirus. No differences were found regarding duration of hospitalisation, oxygen treatment or admittance to the intensive care unit. CONCLUSION: Children with multiple viral findings in their respiratory secretions were older than those with a single detected virus. Otherwise, no major differences in comorbidity, presentation or clinical outcome were observed between the two groups.