Chikungunya infection in returned travellers: results from the geosentinel network, 2005-2020.

BACKGROUND: Chikungunya is an important travel-related disease because of its rapid geographical expansion and potential for prolonged morbidity. Improved understanding of the epidemiology of travel-related chikungunya infections may influence prevention strategies including education and vaccination. METHODS: We analysed data from travellers with confirmed or probable chikungunya reported to GeoSentinel sites from 2005 to 2020. Confirmed chikungunya was defined as a compatible clinical history plus either virus isolation, positive nucleic acid test or seroconversion/rising titre in paired sera. Probable chikungunya was defined as a compatible clinical history with a single positive serology result. RESULTS: 1202 travellers (896 confirmed and 306 probable) with chikungunya were included. The median age was 43 years (range 0-91; interquartile range [IQR]: 31-55); 707 (58.8%) travellers were female. Most infections were acquired in the Caribbean (28.8%), Southeast Asia (22.8%), South Central Asia (14.2%) and South America (14.2%). The highest numbers of chikungunya cases reported to GeoSentinel were in 2014 (28.3%), 2015 (14.3%) and 2019 (11.9%). The most frequent reasons for travel were tourism (n = 592; 49.3%) and visiting friends or relatives (n = 334; 27.7%). The median time to presentation to a GeoSentinel site was 23 days (IQR: 7-52) after symptom onset. In travellers with confirmed chikungunya and no other reported illnesses, the most frequently reported symptoms included musculoskeletal symptoms (98.8%), fever/chills/sweats (68.7%) and dermatologic symptoms (35.5%). Among 917 travellers with information available, 296 (32.3%) had a pretravel consultation. CONCLUSIONS: Chikungunya was acquired by international travellers in almost 100 destinations globally. Vector precautions and vaccination where recommended should be integrated into pretravel visits for travellers going to areas with chikungunya or areas with the potential for transmission. Continued surveillance of travel-related chikungunya may help public health officials and clinicians limit the transmission of this potentially debilitating disease by defining regions where protective measures (e.g. pretravel vaccination) should be strongly considered.

A Prospective Study on the Impact and Out-of-Pocket Costs of Dengue Illness in International Travelers.

Although the costs of dengue illness to patients and households have been extensively studied in endemic populations, international travelers have not been the focus of costing studies. As globalization and human travel activities intensify, travelers are increasingly at risk for emerging and reemerging infectious diseases, such as dengue. This exploratory study aims to investigate the impact and out-of-pocket costs of dengue illness among travelers. We conducted a prospective study in adult travelers with laboratory-confirmed dengue and recruited patients at travel medicine clinics in eight different countries from December 2013 to December 2015. Using a structured questionnaire, we collected information on patients and their health-care utilization and out-of-pocket expenditures, as well as income and other financial losses they incurred because of dengue illness. A total of 90 patients participated in the study, most of whom traveled for tourism (74%) and visited countries in Asia (82%). Although 22% reported hospitalization and 32% receiving ambulatory care while traveling, these percentages were higher at 39% and 71%, respectively, after returning home. The out-of-pocket direct and indirect costs of dengue illness were US$421 (SD 744) and US$571 (SD 1,913) per episode, respectively, averaging to a total out-of-pocket cost of US$992 (SD 2,052) per episode. The study findings suggest that international travelers incur important direct and indirect costs because of dengue-related illness. This study is the first to date to investigate the impact and out-of-pocket costs of travel-related dengue illness from the patient's perspective and paves the way for future economic burden studies in this population.