Epidemiology of imported infectious diseases, China, 2014-18.

BACKGROUND: The frequent movement of population between countries brings an increasing number of travel-related infections. This study aims to define the spectrum and dynamics of imported infections observed from international travel in the Chinese mainland. METHODS: Sick travellers were screened by inbound sentinel surveillance and post-travel clinic visits from 2014 to 18. The infections were classified as respiratory, gastrointestinal, vector-borne, blood/sexually transmitted and mucocutaneous. The analysed variables included the place of origin of the travellers (Chinese or foreign) and the time when travel-related infection was present (at the time of return, during travel and post-travel visits to the clinic). RESULTS: In total, 58 677 cases were identified amongst 1 409 265 253 travellers, with an incidence of 41.64/million, comprising during-travel incidence of 27.44/million and a post-travel incidence of 14.20/million. Respiratory infections constituted the highest proportion of illnesses during travel (81.19%, 31 393 of 38 667), which mainly came from Asian countries and tourists; with influenza virus and rhinovirus infections being mainly diagnosed. Vector-borne diseases constituted the highest proportion of post-travel illnesses (98.14%, 19 638 of 20 010), which were mainly diagnosed from African countries and labourers; with malaria and dengue fever being mainly diagnosed. The differential infection spectrum varied in terms of the traveller's demography, travel destination and travel purpose. As such, a higher proportion of foreign travellers had blood/sexually transmitted diseases (89.85%, 2832 of 3152), while Chinese citizens had a higher prevalence of vector-borne diseases (85.98%, 19 247 of 22 387) and gastrointestinal diseases (79.36%, 1115 of 1405). The highest incidence rate was observed amongst travellers arriving from Africa, while the lowest was observed amongst travellers arriving from Europe. CONCLUSIONS: The findings might help in preparing recommendations for travellers and also aid in primary care or other clinics that prepare travellers before trips abroad. The findings will also help to identify locations and the associated types of infections that might require attention.

Travel demand and distance analysis for free-floating car sharing based on deep learning method.

In order to address the time pattern problems in free-floating car sharing, in this paper, the authors offer a comprehensive time-series method based on deep learning theory. According to car2go booking record data in Seattle area. Firstly, influence of time and location on the free-floating car-sharing usage pattern is analyzed, which reveals an apparent doublet pattern for time and dependence usage amount on population. Then, on the basis of the long-short-term memory recurrent neural network (LSTM-RNN), hourly variation in short-term traffic characteristics including travel demand and travel distance are modeled. The results were also compared with other different statistical models, such as support vector regression (SVR), Autoregressive Integrated Moving Average model (ARIMA), single and second exponential smoothing. It showed that (LSTM-RNN) shows better performance in terms of statistical analysis and tendency precision based on limited data sample.

Interactive Visual Discovering of Movement Patterns from Sparsely Sampled Geo-tagged Social Media Data.

Social media data with geotags can be used to track people's movements in their daily lives. By providing both rich text and movement information, visual analysis on social media data can be both interesting and challenging. In contrast to traditional movement data, the sparseness and irregularity of social media data increase the difficulty of extracting movement patterns. To facilitate the understanding of people's movements, we present an interactive visual analytics system to support the exploration of sparsely sampled trajectory data from social media. We propose a heuristic model to reduce the uncertainty caused by the nature of social media data. In the proposed system, users can filter and select reliable data from each derived movement category, based on the guidance of uncertainty model and interactive selection tools. By iteratively analyzing filtered movements, users can explore the semantics of movements, including the transportation methods, frequent visiting sequences and keyword descriptions. We provide two cases to demonstrate how our system can help users to explore the movement patterns.

The relationship between nature-based tourism and autonomic nervous system function among older adults.

BACKGROUND: Nature-based tourism has recently become a topic of interest in health research. This study was aimed at examining relationships among nature-based tourism, stress, and the function of the autonomic nervous system (ANS). METHODS: Three hundred and twenty-two older adults living in Taichung City, Taiwan, were selected as participants. Data were collected by a face-to-face survey that included measures of the frequency of participation in domestic and international nature-based tourism and the stress and ANS function of these participants. The data were analyzed using a path analysis. RESULTS: The results demonstrated that the frequency of participation in domestic nature-based tourism directly contributed to ANS function and that it also indirectly contributed to ANS function through stress reduction. CONCLUSIONS: Domestic nature-based tourism can directly and indirectly contribute to ANS function among older adults. Increasing the frequency of participation in domestic nature-based tourism should be considered a critical element of health programs for older adults.

Context management platform for tourism applications.

The notion of context has been widely studied and there are several authors that have proposed different definitions of context. However, context has not been widely studied in the framework of human mobility and the notion of context has been imported directly from other computing fields without specifically addressing the tourism domain requirements. In order to store and manage context information a context data model and a context management platform are needed. Ontologies have been widely used in context modelling, but many of them are designed to be applied in general ubiquitous computing environments, do not contain specific concepts related to the tourism domain or some approaches do not contain enough concepts to represent context information related to the visitor on the move. That is why we propose a new approach to provide a better solution to model context data in tourism environments, adding more value to our solution reusing data about tourist resources from an Open Data repository and publishing it as Linked Data. We also propose the architecture for a context information management platform based on this context data model.

Taxonomy of Caribbean tourism alcohol venues: implications for HIV transmission.

BACKGROUND: Tourism areas represent ecologies of heightened HIV vulnerability characterized by a disproportionate concentration of alcohol venues. Limited research has explored how alcohol venues facilitate HIV transmission. METHODS: We spatially mapped locations of alcohol venues in a Dominican tourism town and conducted a venue-based survey of key informants (n=135) focused on three facets of alcohol venues: structural features, type of patrons, and HIV risk behaviors. Using latent class analysis, we identified evidence-based typologies of alcohol venues for each of the three facets. Focused contrasts identified the co-occurrence of classes of structural features, classes of types of patrons, and classes of HIV risk behavior, thus elaborating the nature of high risk venues. RESULTS: We identified three categories of venue structural features, three for venue patrons, and five for HIV risk behaviors. Analysis revealed that alcohol venues with the greatest structural risks (e.g. sex work on-site with lack of HIV prevention services) were most likely frequented by the venue patron category characterized by high population-mixing between locals and foreign tourists, who were in turn most likely to engage in the riskiest behaviors. CONCLUSION: Our results highlight the stratification of venue patrons into groups who engage in behaviors of varying risk in structural settings that vary in risk. The convergence of high-risk patron groups in alcohol venues with the greatest structural risk suggests these locations have potential for HIV transmission. Policymakers and prevention scientists can use these methods and data to target HIV prevention resources to identified priority areas.

International travel patterns and travel risks of patients diagnosed with cancer.

BACKGROUND: Immunocompromised travelers living with cancer can be at increased risk of travel-related illnesses. Their international travel patterns and associated risks remain largely unknown. METHODS: This was a retrospective cohort study of all patients diagnosed with cancer who presented for pre-travel health advice between January 1, 2003 and June 30, 2011. Demographics, travel patterns, and infectious diseases exposure risks of immunocompromised travelers were characterized and compared with those of immunocompetent travelers. Reported travel-related illnesses were assessed in both groups. RESULTS: A total of 149 travelers were included in this study. Fifty-one percent had solid tumors, 32% had hematological malignancies, and 17% underwent stem cell transplantation. Seventy travelers (47%) were immunocompromised. Immunocompromised travelers had similar demographics, trip itineraries, and infectious diseases exposure risks to hepatitis A, malaria, typhoid fever, and yellow fever as immunocompetent travelers. Most of the reported travel-related illnesses were of minor nature. CONCLUSION: Travelers with cancer who have impaired immunity had similar infectious diseases exposure risks and travel patterns as travelers whose cancer is cured or in remission. Improved understanding of travel patterns and risks of patients with cancer may assist in providing more focused pre-travel health interventions to this complex subset of travelers.

The respect of recommendations provided in an international travelers' medical service: far from the cup to the lips.

BACKGROUND: It is not clearly known how frequently the recommendations given to travelers are followed, and what factors could encourage compliance with these recommended measures. METHODS: Adults consulting at a Medical Department for International Travelers (International Travelers' Medical Services, ITMS) in October and November 2010 were asked to answer a questionnaire before their journey. They were also contacted for a post-travel telephone interview to determine whether they had followed the recommendations regarding vaccinations and malaria prevention, and the reasons for poor or noncompliance with these recommendations. RESULTS: A total of 353 travelers were included, with post-travel data available for 321 of them. Complete compliance with all the recommendations (vaccinations and malaria chemoprophylaxis) was observed in 186/321 (57.9%) of the travelers. Only 55.6% (233/419) of the prescribed vaccinations were given, with huge variability according to the type of vaccine. Only 57.3% (184/321) of the patients used a mosquito net. Among the 287 prescriptions for antimalarial drugs, 219 (76.3%) were taken correctly, 37 (12.9%) were taken incorrectly (noncompliance with the duration and/or dosage), and 31 (10.8%) were not taken at all. Traveling to areas of mass tourism (Kenya/Senegal), consulting their general practitioner (GP), and being retired were significantly and independently associated with better overall compliance in univariate and multivariate analyses. CONCLUSIONS: Compliance could be improved by focusing on factors associated with poor compliance to improve the advice given to less compliant travelers, by providing clear information tailored to each traveler, with a focus on key messages, and by improving coordination between ITMS and GPs.

Deaths in international travelers arriving in the United States, July 1, 2005 to June 30, 2008.

BACKGROUND: The Centers for Disease Control and Prevention's (CDC) Quarantine Activity Reporting System (QARS), which documents reports of morbidity and mortality among travelers, was analyzed to describe the epidemiology of deaths during international travel. METHODS: We analyzed travel-related deaths reported to CDC from July 1, 2005 to June 30, 2008, in which international travelers died (1) on a U.S.-bound conveyance, or (2) within 72 hours after arriving in the United States, or (3) at any time after arriving in the United States from an illness possibly acquired during international travel. We analyzed age, sex, mode of travel (eg, by air, sea, land), date, and cause of death, and estimated rates using generalized linear models. RESULTS: We identified 213 deaths. The median age of deceased travelers was 66 years (range 1-95); 65% were male. Most deaths (62%) were associated with sea travel; of these, 111 (85%) occurred in cruise ship passengers and 20 (15%) among cargo and cruise ship crew members. Of 81 air travel-associated deaths, 77 occurred in passengers, 3 among air ambulance patients, and 1 in a stowaway. One death was associated with land travel. Deaths were categorized as cardiovascular (70%), infectious disease (12%), cancer (6%), unintentional injury (4%), intentional injury (1%), and other (7%). Of 145 cardiovascular deaths with reported ages, 62% were in persons 65 years of age and older. Nineteen (73%) of 26 persons who died from infectious diseases had chronic medical conditions. There was significant seasonal variation (lowest in July-September) in cardiovascular mortality in cruise ship passengers. CONCLUSIONS: Cardiovascular conditions were the major cause of death for both sexes. Travelers should seek pre-travel medical consultation, including guidance on preventing cardiovascular events, infections, and injuries. Persons with chronic medical conditions and the elderly should promptly seek medical care if they become ill during travel.

High-risk travel abroad overtook low-risk travel from 1999 to 2004: characterization and trends in 2,622 Spanish travelers.

BACKGROUND: Travel medicine in Spain is provided by a few specialized centers that do not come under the auspices of the main health system. Some kind of reform is required to avoid common summer collapses and postponements of the service. In contrast to other European countries, neither the exact role nor the responsibilities of general practitioners and primary health care in travel medicine are clearly defined. METHODS: An observational study was performed with retrospective data concerning 2,622 travelers from 1999 to 2004. Although the study was performed at a third-level travel medicine center, continuous contact with and support to general practitioners was maintained throughout the period. RESULTS: International travel was a steadily increasing reality between 1999 and 2004 despite well-known tragic events involving world safety. The number of high-risk travels (53.4%) also increased and even overtook low-risk ones (46.6%). This trend was explained as the result of an increasing number of journeys to sub-Saharan Africa (14.9%) and those made by traveling immigrants (64.1% of those journeys), which represented a significantly higher proportion of high-risk travels compared with those made by autochthonous subjects (52.1%; p < .001). Moreover, traveling immigrants tend to consult more frequently in periods < 15 days prior to travel than do autochthonous travelers (p < .0001). A substantial number of highly vulnerable travelers, such as pregnant women, infants, elderly people, and immunosuppressed subjects, was found (1.8%). Low-risk travelers who could have been advised and vaccinated by general practitioners were 1,139 (43.4%). CONCLUSIONS: Given the increasing number of travelers undertaking high-risk travels abroad, any kind of reinforcement of travel medicine provision in Spain should be considered essential. General practitioners could attend to a significant proportion of low-risk travelers.

High prevalence of antibodies against circumsporozoite antigen of Plasmodium falciparum without development of symptomatic malaria in travelers returning from sub-Saharan Africa.

Circumsporozoite (CS) antibodies, indicating that falciparum malaria infection has occurred, have been shown to be reliable indicators of transmission in malaria-endemic areas. In order to estimate the actual rate of malaria infection, the prevalence of CS antibodies in serum was investigated by ELISA in a selected population of travelers returning from sub-Saharan Africa without any clinical sign of malaria. Sera from 39 (48.8%) of 80 individual travelers were positive, while this was only true for 8 (5.6%) of 142 travelers who took package tours. The risk of malaria infection was therefore 8.7 times greater for individual tourists than for package-tour travelers. These data demonstrate the importance of adequate malaria chemoprophylaxis in nonimmune travelers to areas with highly endemic disease.