They are my worries, so it's me the doctor should listen to-adolescent males' experiences of consultations with general practitioners.

BACKGROUND: Many adolescent males visit a general practitioner regularly, yet many report unmet health needs and negative experiences. This indicates a gap between provided healthcare and the needs of adolescent males. In order to improve adolescent males' possibilities to discuss their health concerns with general practitioners, the study's aim was to explore and describe how adolescent males understand and assign meaning to their experiences of consultations with general practitioners. METHODS: This qualitative study was conducted at two healthcare centres in mid-Sweden in 2022. Nine males 15 to 19 years old described their experiences in semi-structured interviews immediately after consulting a general practitioner, regardless of reason for the consultation and whether or not accompanied by a parent. The analysis was guided by thematic analysis according to Braun & Clarke and reflective lifeworld theory's concepts of openness and sensitivity. RESULTS: One overarching theme, To be listened to, and three themes were developed: To handle insecurity and uneasiness, To be understood and cared for, and To get parental support on his terms. In a good appointment, the general practitioner cares about him, listens attentively, and takes him seriously. More importantly, the general practitioner's understanding permeates the consultation, so that all aspects of it is adapted to him. The adolescent males doubted their ability to express themselves and to understand what would happen in the consultation, and therefore feared being dismissed without receiving any help. Such difficulties may be due to unfinished neurocognitive development and inexperience. They struggled with embarrassment, partly due to notions of masculinity, and strived to balance their needs of parental support, privacy, and being the one that the doctor listens to. CONCLUSIONS: We argue that adolescent males are particularly vulnerable due to on-going neurocognitive and emotional development, inexperience, and notions of masculinity. However, good experiences can be generated through rather simple means. Adolescent males need individual adaptations demonstrating that they are cared for, understood and taken seriously. Furthermore, they need an unhurried pace to facilitate understanding, verbal affirmations to mitigate embarrassment, and help in navigating parental involvement.

Unintentional Injuries Are Associated with Self-Reported Child Maltreatment among Swedish Adolescents.

Injuries constitute a large share of childhood morbidity and mortality. This study examines whether adolescents with self-reported experiences of different types of child maltreatment more frequently reported unintentional injury events requiring health- or dental care during the last year and/or hospitalization at any time during childhood. Cross-sectional data from a Swedish national representative school survey (2016) including 4741 adolescents were used (78.5% response rate). Data were analyzed with univariate tests and multiple logistic regression. Statistically significant associations between reported experiences of physical, psychological and sexual abuse, neglect, and witnessing partner violence during childhood and reported unintentional injuries requiring health- or dental care during the last year were found (aOR:s between 1.39-1.77). The corresponding association for poly-victimization was aOR 1.91 (95% CI 1.39-2.62). Furthermore, a linear-by-linear association was seen for degree of victimization and number of episodes of unintentional injuries that required care in the last year (p = 0.000), as well as lifetime hospitalizations (p = 0.000). This study shows significant associations between child maltreatment and unintentional injuries requiring health- and/or dental care and hospitalization. To improve both injury and child maltreatment prevention, healthcare professionals need to pay particular attention to children and adolescents who repeatedly seek healthcare services due to injurious events.

Confidentiality matters! Adolescent males' views of primary care in relation to psychosocial health: a structural equation modelling approach.

OBJECTIVE: To investigate to what degree adolescent males (1) value confidentiality, (2) experience confidentiality and are comfortable asking sensitive questions when visiting a general practitioner (GP), and (3) whether self-reported symptoms of poor mental health and health-compromising behaviours (HCB) affect these states of matters. DESIGN: Cross-sectional. SETTING: School-based census on life, health and primary care in Region Sörmland, Sweden. SUBJECTS: 2,358 males aged 15-17 years (response rate 84%). MAIN OUTCOME MEASURES: The impact of poor mental health and HCBs on adolescent males' valuing and experiencing private time with the GP, having professional secrecy explained, and being comfortable asking about the body, love and sex, analysed with structural equation modelling. RESULTS: Almost all respondents valued confidentiality regardless of their mental health or whether they engaged in HCBs: 86% valued spending private time with the GP, and 83% valued receiving a secrecy explanation. Among those who had visited a GP in the past year (n = 1,200), 74% had experienced private time and 42% a secrecy explanation. Three-quarters were at least partly comfortable asking sensitive questions. Adolescent males with HCBs were more likely to experience a secrecy explanation (approximative odds ratio [appOR] 1.26; p = 0.005) and to be comfortable asking about sex than their peers (appOR 1.22; p = 0.007). Respondents reporting experienced confidentiality were more comfortable asking sensitive questions (appOR 1.25-1.54; p ≤ 0.010). CONCLUSION: Confidentiality matters regardless of poor mental health or HCBs and makes adolescent males more comfortable asking sensitive questions. We suggest that GPs consistently offer private time and explain professional secrecy.Key PointsConfidentiality for adolescent males has been scantily studied in relation to mental health and health-compromising behaviours.In this study, most adolescent males valued confidentiality, regardless of their mental health and health-compromising behaviours.Health-compromising behaviours impacted only slightly, and mental health not at all, on experiences of confidentiality in primary care.When provided private time and an explanation of professional secrecy, adolescent males were more comfortable asking the GP sensitive questions.

Understanding adolescent males' poor mental health and health-compromising behaviours: A factor analysis model on Swedish school-based data.

AIM: The aim was to develop a factor model of the clustering of poor mental-health symptoms and health-compromising behaviours (HCBs) in adolescent males. METHODS: The study was based on two cross-sectional school-based Swedish surveys in 2011 (response rate 80%, N=2823) and 2014 (response rate 85%, N=2358), both of which comprised questionnaires from males aged 15-16 and 17-18 years. A factor model was developed by exploratory factor analysis on the 2011 survey and validated by confirmatory factor analysis on the 2014 survey. RESULTS: Four aspects of poor mental health and HCBs emerged in the exploratory factor analysis: (a) deviancy as a tendency to substance use and delinquency, (b) unsafety as an inclination towards feelings of unsafety in different environments, (c) gloominess as a tendency towards pessimism and feeling unwell and (d) pain as an inclination to experience physical pain. The model was validated with good model fit. Age did not affect the model structure, but older adolescent males were more influenced by deviancy and gloominess and less by unsafety compared to their younger peers. Conclusions: Separating symptoms of poor mental health and HCBs into four areas - deviancy, unsafety, gloominess and pain - brings new perspectives to the understanding of adolescent males' health. To the best of our knowledge, our factor model is the first to include unsafety and pain in this context. Whenever a comprehensive approach to the health of adolescent males is needed in the clinic or in the field of public health, this factor model may provide guidance.

Perceived needs for team-based visits in Swedish child healthcare services exceed its existence-A mixed-methods study targeting healthcare professionals.

AIM: To investigate both quantitatively and qualitatively the differences between participation in team-based visits (TBVs) and perceived needs for TBVs from the perspectives of healthcare professionals, in the context of the Swedish 3-tier national Child Healthcare programme. METHODS: A study-specific questionnaire, including multiple-choice questions with fixed and free-text response options, was developed, and used. To capture healthcare professionals' experiences and find explanations for the quantitative results in qualitative data, a convergent parallel mixed-methods study design was used. Descriptive statistics and McNemar's test were used to analyse the quantitative data, and content analysis was used to analyse the qualitative data. RESULTS: Healthcare professionals perceived the need for TBVs in the Swedish Child Healthcare Services (CHS) to a high extent. The largest difference between the perceived need for TBVs and experienced TBVs was for indications associated with psychosocial problems. The quantitative findings were explored by the qualitative findings. Both individual and organisational factors influenced TBVs. CONCLUSION: Perceived needs for TBVs in Swedish CHS exceed its existence. Healthcare professionals require TBVs delivered by interprofessional teams, in line with proportionate universalism. Accordingly, organisational structures (e.g. colocation and clear instructions on how to distribute TBVs) and human resources (e.g. psychologists and social worker) are needed.

Team-based visits within Swedish child healthcare services: a national cross-sectional study.

Complex healthcare needs can be met through effective interprofessional collaboration. Since 2014, Swedish Child Healthcare Services (CHS) include universal team-based visits with a nurse and a physician who perform such visits at the age of 4 weeks, 6 months, 12 months, and 2.5 to 3 years, as well as targeted team-based visits to address additional needs. The aim of this study was to describe the prevalence of team-based visits in the Swedish CHS and possible associations between team-based visits and contextual factors that may affect its implementation. A national cross-sectional survey was conducted using a web-based questionnaire distributed to all reachable nurses, physicians, and psychologists (n =3,552) engaged in the CHS. Data were analyzed using descriptive statistics and binary and multivariate logistic regressions. The response rate was 32%. Team-based visits were reported by 82% of the respondents. For nurses and physicians, the most frequent indication was specific ages, while for psychologists it was to provide parental support. Respondents working at Family Centers were more likely to perform team-based visits in general, at 2.5 to 3 years and in case of additional needs, compared to respondents working at Child Health Centers (CHC) and other workplaces. In conclusion, team-based visits are well implemented, but the pattern differs depending on the contextual factors. Targeted team-based visits and team-based visits at the age of 2.5 to 3 years are most unequally implemented.

Healthcare professionals' perceptions about interprofessional teamwork: a national survey within Swedish child healthcare services.

BACKGROUND: Globally, interprofessional teamwork is described as a key method to promote health and prevent illness in children, namely, to achieve the goals of Child Healthcare Services (CHS). However, how teamwork should be designed within CHS to achieve the goals is unclear. This study aimed to investigate healthcare professionals' perceptions about 1) taking part in interprofessional teamwork, 2) team characteristics, and 3) whether the perceptions were related to professional affiliation or workplace. METHODS: A national cross-sectional survey was conducted using a web-based study-specific questionnaire sent to all accessible nurses, physicians, and psychologists in Swedish CHS (n = 3552). The response rate was 31.5%. To identify possible associations, logistic regressions were conducted. RESULTS: Almost all respondents, 1096/1119 (97.9%), reported taking part in some type of interprofessional teamwork within the Swedish CHS. Among those, the most common was team-based visits (82.2%). It was perceived that performing team-based visits resulted in fulfilled goals, expertise exceeding individual team members' competences, provision of high-quality care, and meeting children's and families' needs, to a greater extent, than if not performing team-based visits. Correspondingly, working as a team in parental groups was perceived as resulting in fulfilled goals, meeting the needs of children and their families, and continuity within the team to a greater extent than if not working together in a team. Professional affiliation was associated with different perceptions and types of teamwork. Family Centers were positively associated with all types of teamwork as well as continuity within the team. CONCLUSIONS: Healthcare professionals' perceptions about team characteristics were associated with professional affiliation, workplace, and type of teamwork (defined as team activities) within the CHS. Professionals within Swedish CHS, taking part in team-based visits and in interprofessional teamwork in parental groups, perceived that the team fulfilled its goals and met the needs of children and families to a greater extent than professionals not taking part in these types of teamwork. Professionals at Family Centers were more likely to work in teams in different ways. Knowledge about interprofessional teamwork for individuals and groups in Swedish CHS might also be valuable in other healthcare settings, dealing with complex needs.

Poor School-Related Well-Being among Adolescents with Disabilities or ADHD.

Poor school-related well-being may influence adolescents' school performance and lifestyle. Adolescents having disabilities or ADHD are in a vulnerable situation for having poor school-related well-being, compared to adolescents not having disabilities. We used cross-sectional data from a school-based survey among 15-18-year-olds (N = 4071) in Sörmland, Sweden, to analyse the association between poor school-related well-being and disabilities or ADHD. The analyses were carried out by logistic regression models, adjusting for background factors, school-related factors, and health-compromising behaviours. Adolescents having disabilities (n = 827) or ADHD (n = 146) reported that their disability had a negative influence on school. Compared to peers without disability, those having disabilities had an increased chance (OR = 1.40 95% CI: 1.17-1.68) of poor school-related well-being. The corresponding OR was doubled for adolescents reporting ADHD (2.23 95% CI: 1.56-3.18). For the ADHD group, the adjOR for poor school-related well-being remained significant (1.67 95% CI: 1.13-2.50) after adjustments for school-related factors and health-compromising behaviours, but not for the disability group. In conclusion, adolescents having ADHD are a particularly vulnerable group at school, having a greater risk of poor school-related well-being. Schools should actively work to achieve school satisfaction for adolescents having disabilities, to ensure that all students have similar opportunities for favourable development, health and achievement of their academic goals.

Self- and parent-reported executive problems in adolescents with type 1 diabetes are associated with poor metabolic control and low physical activity.

BACKGROUND: Management of diabetes is demanding and requires efficient cognitive skills, especially in the domain of executive functioning. However, the impact of impaired executive functions on diabetes control has been studied to a limited extent. The aim of the study is to investigate the association between executive problems and diabetes control in adolescents with type 1 diabetes. MATERIALS AND METHODS: Two hundred and forty-one of 477 (51%) of 12- to 18-year-old adolescents, with a diabetes duration of >2 years in Stockholm, Uppsala, and Jönköping participated. Parents and adolescents completed questionnaires, including Behavioral Rating Inventory of Executive Function (BRIEF), Attention-Deficit/Hyperactivity Disorder (ADHD)-Rating Scale (ADHD-RS) and demographic background factors. Diabetes-related data were collected from the Swedish Childhood Diabetes Registry, SWEDIABKIDS. Self-rated and parent-rated executive problems were analyzed with regard to gender, glycosylated hemoglobin (HbA1c), frequency of outpatient visits, and physical activity, using chi-square tests or Fisher's test, where P-values <.05 were considered significant. Furthermore, adjusted logistic regressions were performed with executive problems as independent variable. RESULTS: Executive problems, according to BRIEF and/or ADHD-RS were for both genders associated with mean HbA1c >70 mmol/mol (patient rating P = .000, parent rating P = .017), a large number of outpatient visits (parent rating P = .015), and low physical activity (patient rating P = .000, parent rating P = .025). Self-rated executive problems were more prevalent in girls (P = .032), while parents reported these problems to a larger extent in boys (P = .028). CONCLUSION: Executive problems are related to poor metabolic control in adolescents with type 1 diabetes. Patients with executive problems need to be recognized by the diabetes team and the diabetes care should be organized to provide adequate support for these patients.

Continuous subcutaneous glucose monitoring is accurate in term and near-term infants at risk of hypoglycaemia.

AIM: Postnatal hypoglycaemia increases the risk of adverse neurological outcomes in newborn infants, and adequate glucose control requires repetitive and painful blood sampling. This study evaluated a continuous glucose monitoring system (CGMS) that aims to improve glucose control and decrease the frequency of blood samples taken from neonates. METHODS: CGMS sensors, which measure glucose values every five minutes and require calibration twice a day, were placed on 20 infants at risk of hypoglycaemia. The infants also underwent blood glucose sampling, and the blood glucose values were compared with CGMS values six times during the first 30 minutes after sampling. RESULTS: We used 97/264 (37%) of the blood glucose values taken for the CGMS calibration. The highest accuracy, a mean of 0.22 (95% confidence interval 0.13-0.30 mmol/L), was found 15-19 minutes after sampling, due to the calibration process. No significant subcutaneous glucose time lag was detectable. CONCLUSION: The CGMS system was an accurate and feasible method for glucose control, provided earlier detection of hypoglycaemia in newborn infants and reduced their exposure to procedural pain. The delay in calibration in infants was a new finding and needs to be taken into account when comparing CGMS readings to blood glucose values.

Bully, bullied and abused. Associations between violence at home and bullying in childhood.

AIMS: The aim was to examine experiences of bullying among Swedish adolescents and whether victims and perpetrators were also exposed to violence in the home, with particular focus on how abuse severity affected the risk of exposure to bullying. METHODS: A nationally representative sample of pupils aged 14-15 responded to a questionnaire exploring exposure to corporal punishment and other types of violence. Results were analysed using Pearson's chi-square and multiple logistic regression, adjusting for factors regarding the child, the parents and the families' socioeconomic status. RESULTS: Among the 3197 respondents, a significant proportion reported at least one incident of either bullying victimisation (girls 36%, boys 26%) or bullying perpetration (girls 24%, boys 36%). Physical and emotional violence in the home, including witnessed intimate partner violence, were significantly associated with both bullying victimisation and bullying perpetration. Odds ratios for exposure to bullying rose with increasing frequency and severity of abuse. Adjusted odds ratios ranged from 1.6 for any event of abuse vs. single episodes of bullying to 20.3 for multiple types of abuse vs. many episodes of bullying. The child's gender and the presence of a chronic health condition were consistently associated with nearly all levels of abuse and bullying. CONCLUSIONS: Bullying experiences are common among youth and are clearly associated with abuse. Frequent bullying, whether as victim or perpetrator, warrants particular vigilance, as it appears to be an indicator of severe violence in the home.

Chronic conditions and coexisting ADHD-a complicated combination in adolescents.

Adolescents with chronic conditions (CCs) take more health risks than peers. However, coexisting ADHD has not sufficiently been considered. The aim of the present study was to investigate the impact of different CCs on protective factors and health-risk behaviors, taking coexisting ADHD into account. A school-based study among 6895 15- and 17-year-old students was performed in the county of Sörmland, Sweden in 2011 (response rate 80 %). The questionnaire explored background factors, CCs, protective factors, and health-risk behaviors. CCs were reported by 11 %, while 55 % were healthy. Students with CCs more often reported coexisting ADHD than healthy students. In adolescents with neurological conditions, the odds ratio for having ADHD was 7.34 (95 % CI 3.00-17.99) as compared to healthy peers. Few protective factors (<4) and clustered health-risk behaviors (≥4) were more common among students with CCs, especially if ADHD or a combination including ADHD was reported. CONCLUSION: CCs and coexisting ADHD are associated with few protective factors and clustered-health risk behaviors. Adolescents with ADHD-in addition to a chronic condition-should be specially acknowledged by health care professionals in order to prevent health risk behaviors. ADHD should be considered when studying these outcomes in adolescents. WHAT IS KNOWN: • Youth with chronic conditions (CCs)-especially ADHD-are reported to take more health risks than peers. • In earlier studies of youth with CCs, the presence of coexisting ADHD has not been taken into account. WHAT IS NEW: • In this study, we showed that ADHD was more prevalent among adolescents with different types of CCs. • CCs and coexisting ADHD were associated with few protective factors and clustered health-risk behaviors.

Quality of life among Swedish school children who experienced multitype child maltreatment.

AIM: The aim of this study was to examine the overlap between child maltreatment types and their association with quality of life among school children. METHODS: A national cross-sectional study of 3202 grade nine Swedish pupils of 15 years of age was carried out in 2011 with an 84% response rate. Data were analysed using Pearson chi-square and multiple linear regression analyses. RESULTS: Of the total sample, 650 children (20%) reported at least one type of maltreatment. There was a large degree of overlap between maltreatment types. In particular, neglect and witnessing intimate partner violence overlapped with most other types of maltreatment. There was a significant relationship between the degree of abuse and multitype maltreatment. Results showed a linear relationship between the number of types of maltreatment and quality of life (p < 0.001), indicating a dose-response relationship. CONCLUSION: The results emphasise the negative impact of child maltreatment on children's lives and highlight the importance of taking the broad spectrum of child maltreatment into account in both research and practice. A more comprehensive assessment of the width of maltreatment among professionals may help to identify the most seriously maltreated children and lead to an improved ability to target intervention and prevention at these children.

[Injuries from violence in young children--signs, management and diagnostics]. / Special: Barn som far illa - Skador av våld hos små barn - tecken, handläggning och diagnostik.

Inflicted injuries in infants and toddlers may easily be missed unless clinicians who care for children are alert to sometimes subtle clues in the history and physical exam. Any injury which is unexplained or incompatible with the developmental capabilities of the child or inconsistent with the given history should prompt a medical evaluation for suspected physical abuse. The most common cause of serious head injuries in infants younger than 12 months is child abuse. Shaking and blunt head trauma can result in injuries such as subdural hemorrhage, diffuse retinal hemorrhage, and brain and spine injury. Early detection of child physical abuse requires a systematic and careful diagnostic approach. The physician must be able to recognize suspicious injuries, as well as possess an understanding of the mimics that may be confused with inflicted injuries. Health care professionals are mandated by Swedish law to promptly report suspected abuse to child protective services.

The triply troubled teenager--chronic conditions associated with fewer protective factors and clustered risk behaviours.

AIM: This study aimed to measure protective factors and risk behaviour among adolescents with chronic conditions (CCs) and to evaluate the impact of protective factors on risk-taking. METHODS: A population-based study of 7262 students aged 15 and 17 years old was performed in Sörmland, Sweden 2008 (response rate 82%). The questionnaire explored background factors, CCs, risk behaviours and protective factors. CCs were reported by 8%, while 58% had no health problems. RESULTS: Girls with CCs encompassed less individual protective factors, while boys with CCs tended to over-report all individual risk behaviours compared with healthy peers. Both boys and girls with CCs were more likely to report few protective factors and co-occurrence of risk behaviours. The adjOR for clustered health risk behaviours was 1.6 (1.0-2.5) in youths with CCs and ≥4 protective factors and 6.3 (3.6-10.9) in youths with CCs and 0-3 protective factors, as compared to healthy peers with ≥4 protective factors. CONCLUSION: Adolescents with CCs reported fewer protective factors and more risk behaviours than their healthy peers. The vulnerability of adolescents with CCs and few protective factors is important to acknowledge. Professionals should provide stronger protection for these adolescents, to prevent risky behaviour.

Children and adolescents with type 1 diabetes and high HbA1c -- a neurodevelopmental perspective.

AIM: To examine the association between neurodevelopmental problems and high HbA1c among paediatric patients with type 1 diabetes. METHODS: A population-based study was performed among patients with type 1 diabetes (5-16 years) in two Swedish counties (n = 233). The Five to Fifteen (FTF) questionnaire targeted neurodevelopmental qualities. Scores above the 90th percentile in the various domains are considered as definitive problems and scores above the 75th percentile as mild. FTF scores were compared with regard to HbA1c ≤73 mmol/mol and >73 mmol/mol (8.0%). RESULTS: The response rate was 190 (82%). Neurodevelopmental problems were not overrepresented among patients in general. Memory and learning problems were associated with HbA1c >73 mmol/mol (p = 0.01). This correlation was especially seen in adolescents (12-16 years) where mild executive problems (adjOR 3.1), definite memory problems (adjOR 5.0) and definite learning problems (adjOR 5.0) were associated with HbA1c >73 mmol/mol after adjustment for gender, diabetes duration and age of onset. CONCLUSION: Our findings that high HbA1c is more common in adolescent diabetes patients with neurodevelopmental problems generate the hypothesis that these problems might precede poor metabolic control. If so, early detection of neurodevelopmental problems would allow individually tailored treatment that may improve metabolic control and prevent complications.

Multiple psychosomatic symptoms can indicate child physical abuse - results from a study of Swedish schoolchildren.

AIM: To examine whether children with self-reported experiences of either physical abuse alone or combined with intimate partner violence report more psychosomatic symptoms than other children and to explore whether these possible associations are enhanced by school-related factors, chronic condition and demographic factors. METHODS: A national cross-sectional study of 2771 pupils in grades 4, 6 and 9 from 44 schools in Sweden was carried out in 2006 (91% response rate). Data were analysed with univariate tests (chi-square), multiple logistic regression analyses and stratified logistic regression analyses, expressed as crude odds ratio (OR) and adjusted odds ratio (AOR) with 95% confidence intervals. RESULTS: There was a strong association between reported physical abuse and multiple (three or more) psychosomatic symptoms among schoolchildren (AOR 2.12). Chronic condition was the only determinant that had an obvious enhancing effect on the association between physical abuse and psychosomatic symptoms in childhood. CONCLUSION: This study shows that multiple psychosomatic symptoms are associated with child physical abuse. Health professionals therefore need to pay special attention to schoolchildren who complain about the co-occurrence of psychosomatic symptoms and pattern of symptoms, which could not be easily explained by other causes.

Helicobacter pylori genome variability in a framework of familial transmission.

BACKGROUND: Helicobacter pylori infection is exceptionally prevalent and is considered to be acquired primarily early in life through person-to-person transmission within the family. H. pylori is a genetically diverse bacterial species, which may facilitate adaptation to new hosts and persistence for decades. The present study aimed to explore the genetic diversity of clonal isolates from a mother and her three children in order to shed light on H. pylori transmission and host adaptation. RESULTS: Two different H. pylori strains and strain variants were identified in the family members by PCR-based molecular typing and sequencing of five loci. Genome diversity was further assessed for 15 isolates by comparative microarray hybridizations. The microarray consisted of 1,745 oligonucleotides representing the genes of two previously sequenced H. pylori strains. The microarray analysis detected a limited mean number (+/- standard error) of divergent genes between clonal isolates from the same and different individuals (1 +/- 0.4, 0.1%, and 3 +/- 0.3, 0.2%, respectively). There was considerable variability between the two different strains in the family members (147 +/- 4, 8%) and for all isolates relative to the two sequenced reference strains (314 +/- 16, 18%). The diversity between different strains was associated with gene functional classes related to DNA metabolism and the cell envelope. CONCLUSION: The present data from clonal H. pylori isolates of family members do not support that transmission and host adaptation are associated with substantial sequence diversity in the bacterial genome. However, important phenotypic modifications may be determined by additional genetic mechanisms, such as phase-variation. Our findings can aid further exploration of H. pylori genetic diversity and adaptation.

Helicobacter pylori occurrence and transmission: a family affair?

About half of the world's population is estimated to be infected with Helicobacter pylori, a gastric bacterium that contributes to the development of peptic ulcer disease and gastric cancer. H. pylori is more prevalent in low-income areas of the world and social and economic development decreases the prevalence as reflected in comparisons both within and between countries. The infection is typically acquired in early childhood and once established commonly persists throughout life unless treated. Person-to-person transmission within the family appears to be the predominant mode of transmission, particularly from mothers to children and among siblings, indicating that intimate contact is important. The route of transmission is uncertain, but the gastro-oral, oral-oral and faecal-oral routes are likely possibilities. Hence, gastroenteritis may facilitate dissemination of the infection. The community and environment may play additional roles for H. pylori transmission in some (low-income) settings. Furthermore, host and bacterial factors may modify the probabilities of acquisition and persistence of the infection. The understanding of H. pylori occurrence and transmission is of practical importance if future study deems prevention of the infection desirable in some high-prevalence populations. The present paper reviews aspects of H. pylori occurrence and transmission with an emphasis on household factors.