Using Big Data to Monitor the Introduction and Spread of Chikungunya, Europe, 2017.

With regard to fully harvesting the potential of big data, public health lags behind other fields. To determine this potential, we applied big data (air passenger volume from international areas with active chikungunya transmission, Twitter data, and vectorial capacity estimates of Aedes albopictus mosquitoes) to the 2017 chikungunya outbreaks in Europe to assess the risks for virus transmission, virus importation, and short-range dispersion from the outbreak foci. We found that indicators based on voluminous and velocious data can help identify virus dispersion from outbreak foci and that vector abundance and vectorial capacity estimates can provide information on local climate suitability for mosquitoborne outbreaks. In contrast, more established indicators based on Wikipedia and Google Trends search strings were less timely. We found that a combination of novel and disparate datasets can be used in real time to prevent and control emerging and reemerging infectious diseases.

Attack rates of dengue fever in Swedish travellers.

BACKGROUND: Dengue is endemic in many countries visited by Swedish travellers. We aimed to determine the attack rate of dengue in Swedish travellers and analyse the trends over time and the geographical variation. METHODS: We obtained the following data from the Swedish Institute for Communicable Disease Control for the y 1995-2010: number of Swedish residents with confirmed dengue, the country and year of infection. We also obtained registers on the Swedish annual air traveller arrivals to dengue endemic areas from the United Nations World Tourist Organization for the time period. We estimated attack rates with 95% confidence intervals (CI). RESULTS: In total, 925 Swedish travellers with confirmed dengue were reported. We found an increasing trend over time for most destinations. The majority of the dengue cases were acquired in Thailand (492 out of 925 travellers; 53%), with an attack rate of 13.6 (95% CI 12.7, 14.4) per 100,000 travellers. However, the 2 highest attack rates per 100,000 travellers were found for Sri Lanka (45.3, 95% CI 34.3, 56.4) and Bangladesh (42.6, 95% CI 23.8, 61.5). CONCLUSIONS: Information on attack rates in travellers is more helpful in guiding travel medicine practitioners than reports of absolute numbers, as the latter reflect travel preferences rather than the true risk. Although the majority of dengue infections in Swedish travellers were acquired in Thailand, the attack rates for dengue in travellers to Sri Lanka and Bangladesh were much higher. These data aid in refining information on the risk of dengue in travellers.

Social inequalities in social-emotional problems among preschool children: a population-based study in Sweden.

BACKGROUND: Social-emotional ability is important for overall health and wellbeing in early childhood. Recognizing preschool children in need of extra support, especially those living in unfavourable conditions, can have immediate positive effects on their health and benefit their wellbeing in the long-term. OBJECTIVES: The aim of this study is to investigate whether there are social inequalities in preschool children's social-emotional problems, and whether inequalities differ between boys and girls. METHOD: This study utilized repeated measures from cross-sectional population-based surveys of three-year old children (2014-2018). The final study population comprised of 9,099 children which was 61% of all the eligible children in Västerbotten County during the study period. The Ages and Stages Questionnaires: Social-Emotional (ASQ:SE) 36-month interval was used to measure children's social-emotional ability. Social inequalities were studied with respect to parents' income, education, and place of birth, for which data was obtained from Statistics Sweden. Multiple logistic and ordered regressions were used. RESULTS: Among 3-year-olds, social-emotional problems were more common in the most vulnerable social groups, i.e. parents in the lowest income quintile (OR: 1.45, p < 0.001), parents with education not more than high school (OR: 1.51, p < 0.001), and both parents born outside Sweden (OR: 2.54, p < 0.001). Notably, there was a larger difference in social-emotional problems between the lowest and highest social categories for girls compared to boys. Higher odds of social-emotional problems were associated with boys not living with both parents and girls living in the areas of Skellefteå and Umeå, i.e. more populated geographical areas. CONCLUSION: Already at 3-years of age social-emotional problems were more common in children with parents in the most vulnerable social groups. This does not fulfil the ambition of an equitable start in life for every child and might contribute to reproduction of social inequalities across generations.

Childhood onset inflammatory bowel disease: predictors of delayed diagnosis from the CEDATA German-language pediatric inflammatory bowel disease registry.

OBJECTIVES: To examine predictors of delayed diagnosis of inflammatory bowel disease in children and adolescents. STUDY DESIGN: A total of 2,436 patients (age 0-18 years) with Crohn's disease, ulcerative colitis, or unclassified colitis were included from 53 pediatric gastroenterologists. Predictors were examined with the proportional hazards model, presented as hazard ratios (HR) with 95% confidence intervals. HR < 1.0 represent factors associated with late diagnosis. RESULTS: Median time to diagnosis was 4 (2-8) months. Crohn's disease (HR 0.62; 0.56-0.68), and within Crohn's disease, ileal disease (HR 0.77, 95% confidence interval 0.67 to 0.89) were associated with delayed diagnosis. Chances for early diagnosis increased with increasing age (HR 1.07 per year of age; 1.06 to 1.08). There was also an effect by center (HR 0.63, 0.52 to 0.67), but not by sex or country (Austria vs Germany). Growth failure was more common in those cases with delayed diagnosis. CONCLUSIONS: There is still concern about delays in the diagnosis of inflammatory bowel disease in the very young and in children with small bowel disease. Inequalities of care by region require further investigation.

Increased Risk of Drug-Induced Hyponatremia during High Temperatures.

PURPOSE: To investigate the relationship between outdoor temperature in Sweden and the reporting of drug-induced hyponatremia to the Medical Products Agency (MPA). METHODS: All individual adverse drug reactions (ADR) reported to MPA from 1 January 2010 to 31 October 2013 of suspected drug-induced hyponatremia and random controls were identified. Reports where the ADR had been assessed as having at least a possible relation to the suspected drug were included. Information on administered drugs, onset date, causality assessment, sodium levels, and the geographical origin of the reports was extracted. A case-crossover design was used to ascertain the association between heat exposure and drug-induced hyponatremia at the individual level, while linear regression was used to study its relationship to sodium concentration in blood. Temperature exposure data were obtained from the nearest observation station to the reported cases. RESULTS: During the study period, 280 reports of hyponatremia were identified. More cases of drug-induced hyponatremia were reported in the warmer season, with a peak in June, while other ADRs showed an opposite annual pattern. The distributed lag non-linear model indicated an increasing odds ratio (OR) with increasing temperature in the warm season with a highest odds ratio, with delays of 1-5 days after heat exposure. A cumulative OR for a lag time of 1 to 3 days was estimated at 2.21 at an average daily temperature of 20 °C. The change in sodium per 1 °C increase in temperature was estimated to be -0.37 mmol/L (95% CI: -0.02, -0.72). CONCLUSIONS: Warm weather appears to increase the risk of drug-induced hyponatremia.

Environmental Suitability of Vibrio Infections in a Warming Climate: An Early Warning System.

BACKGROUND: Some Vibrio spp. are pathogenic and ubiquitous in marine waters with low to moderate salinity and thrive with elevated sea surface temperature (SST). OBJECTIVES: Our objective was to monitor and project the suitability of marine conditions for Vibrio infections under climate change scenarios. METHODS: The European Centre for Disease Prevention and Control (ECDC) developed a platform (the ECDC Vibrio Map Viewer) to monitor the environmental suitability of coastal waters for Vibrio spp. using remotely sensed SST and salinity. A case-crossover study of Swedish cases was conducted to ascertain the relationship between SST and Vibrio infection through a conditional logistic regression. Climate change projections for Vibrio infections were developed for Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. RESULTS: The ECDC Vibrio Map Viewer detected environmentally suitable areas for Vibrio spp. in the Baltic Sea in July 2014 that were accompanied by a spike in cases and one death in Sweden. The estimated exposure-response relationship for Vibrio infections at a threshold of 16°C revealed a relative risk (RR)=1.14 (95% CI: 1.02, 1.27; p=0.024) for a lag of 2 wk; the estimated risk increased successively beyond this SST threshold. Climate change projections for SST under the RCP 4.5 and RCP 8.5 scenarios indicate a marked upward trend during the summer months and an increase in the relative risk of these infections in the coming decades. CONCLUSIONS: This platform can serve as an early warning system as the risk of further Vibrio infections increases in the 21st century due to climate change. https://doi.org/10.1289/EHP2198.

Laboratory-Enhanced Dengue Sentinel Surveillance in Colombo District, Sri Lanka: 2012-2014.

INTRODUCTION: Dengue has emerged as a significant public health problem in Sri Lanka. Historically surveillance was passive, with mandatory dengue notifications based on clinical diagnosis with only limited laboratory confirmation. To obtain more accurate data on the disease burden of dengue, we set up a laboratory-based enhanced sentinel surveillance system in Colombo District. Here we describe the study design and report our findings of enhanced surveillance in the years 2012-2014. METHODS: Three outpatient clinics and three government hospitals in Colombo District that covered most of the Colombo metropolitan area were selected for the sentinel surveillance system. Up to 60 patients per week presenting with an undifferentiated fever were enrolled. Acute blood samples from each patient were tested by dengue specific PCR, NS1 ELISA and IgM ELISA. A sub-set of samples was sent to Duke-NUS Singapore for quality assurance, virus isolation and serotyping. Trained medical research assistants used a standardized case report form to record clinical and epidemiological data. Clinical diagnoses by the clinicians-in-charge were recorded for hospitalized cases. RESULTS: Of 3,127 febrile cases, 43.6% were PCR and/or NS1 positive for dengue. A high proportion of lab confirmed dengue was observed from inpatients (IPD) (53.9%) compared to outpatient (clinics in hospitals and general practice) (7.6%). Dengue hemorrhagic fever (DHF) was diagnosed in 11% of patients at the time of first contact, and the median day of illness at time of presentation to the sentinel sites was 4. Dengue serotype 1 was responsible for 85% of the cases and serotype 4 for 15%. The sensitivity and specificity of the clinicians' presumptive diagnosis of dengue was 84% and 34%, respectively. CONCLUSION: DENV-1, and to a lesser degree DENV-4, infection were responsible for a high proportion of febrile illnesses in Colombo in the years 2012 to 2014. Clinicians' diagnoses were associated with high sensitivity, but laboratory confirmation is required to enhance specificity.

The Umwelt of an embodied agent--a measure-theoretic definition.

We consider a general model of the sensorimotor loop of an agent interacting with the world. This formalises Uexküll's notion of a function-circle. Here, we assume a particular causal structure, mechanistically described in terms of Markov kernels. In this generality, we define two σ-algebras of events in the world that describe two respective perspectives: (1) the perspective of an external observer, (2) the intrinsic perspective of the agent. Not all aspects of the world, seen from the external perspective, are accessible to the agent. This is expressed by the fact that the second σ-algebra is a subalgebra of the first one. We propose the smaller one as formalisation of Uexküll's Umwelt concept. We show that, under continuity and compactness assumptions, the global dynamics of the world can be simplified without changing the internal process. This simplification can serve as a minimal world model that the system must have in order to be consistent with the internal process.