Journal of Travel Medicine
Chikungunya, an arboviral disease transmitted primarily by Aedes aegypti and Aedes albopictus mosquitos, has re-emerged globally since 2004, expanding from tropical regions to temperate zones.1 While Latin America and the Caribbean bear 80% of the global disability-adjusted life year (DALY) burden,2 data on the economic impact—specifically out-of-pocket (OOP) costs—remain scarce.3 This research letter reports OOP costs incurred by returning travellers who contracted chikungunya during the 2022–23 Paraguay outbreak. While local surveillance systems monitored residents, the GeoSentinel network—a global collaboration between the US Centers for Disease Control and Prevention (CDC) and the International Society of Travel Medicine (ISTM)4—monitored the impact on travellers, marking the first time this network investigated cost outcomes during a specific chikungunya epidemic.
This prospective observational study was conducted at three hospital-based clinics in Spain (La Paz-Carlos III University Hospital, Madrid; Vall d’Hebron University Hospital, Barcelona; and Hospital Clínic de Barcelona, Barcelona) and one hospital-based clinic in Argentina (Hospital F. J. Muñiz, Buenos Aires), all of which are part of the GeoSentinel network. Eligible participants were returning travellers who experienced a clinically compatible illness and symptom onset during the 2022–23 chikungunya outbreak in Paraguay and presented for consultation at participating clinics upon return. Participants were recruited within 12 months of reported symptom onset, and all of them underwent serologic testing using antibody detection assays at participating clinics. Onset of symptoms to diagnosis was a median of 19 days [interquartile range (IQR): 5–43 days]. Confirmed cases were RT-PCR-positive; probable cases had positive Immunoglobulin M (IgM) or Immunoglobulin G (IgG) serology. Participants were followed up at a median of 13.4 months (IQR: 11.3–15.9 months) of diagnosis between 5 March– and 7 November 2024, with a structured, self-administered questionnaire in Spanish. The full patient questionnaire used in this study is available as Supplementary Material. The questionnaire, which was completed in person on paper, elicited data on demographics, travel history and clinical impact, and the cost module covered direct and indirect OOP expenditures since symptom onset. OOP costs were categorized by setting and location. Direct costs included medical consultations and medications, while indirect costs included income loss and nonrefundable travel expenses. Patients’ OOP expenditures covered by health insurance were excluded from calculations. Costs were estimated via self-reports and expressed in 2023 US dollars (USD).5 All the clinics obtained Institutional Review Board approval, and all the data were anonymized.
EVENTS
FAQ
Journal
Journal of Travel Medicine
DOI
https://doi.org/10.1093/jtm/taag019
Abstract
Chikungunya, an arboviral disease transmitted primarily by Aedes aegypti and Aedes albopictus mosquitos, has re-emerged globally since 2004, expanding from tropical regions to temperate zones.1 While Latin America and the Caribbean bear 80% of the global disability-adjusted life year (DALY) burden,2 data on the economic impact—specifically out-of-pocket (OOP) costs—remain scarce.3 This research letter reports OOP costs incurred by returning travellers who contracted chikungunya during the 2022–23 Paraguay outbreak. While local surveillance systems monitored residents, the GeoSentinel network—a global collaboration between the US Centers for Disease Control and Prevention (CDC) and the International Society of Travel Medicine (ISTM)4—monitored the impact on travellers, marking the first time this network investigated cost outcomes during a specific chikungunya epidemic.
This prospective observational study was conducted at three hospital-based clinics in Spain (La Paz-Carlos III University Hospital, Madrid; Vall d’Hebron University Hospital, Barcelona; and Hospital Clínic de Barcelona, Barcelona) and one hospital-based clinic in Argentina (Hospital F. J. Muñiz, Buenos Aires), all of which are part of the GeoSentinel network. Eligible participants were returning travellers who experienced a clinically compatible illness and symptom onset during the 2022–23 chikungunya outbreak in Paraguay and presented for consultation at participating clinics upon return. Participants were recruited within 12 months of reported symptom onset, and all of them underwent serologic testing using antibody detection assays at participating clinics. Onset of symptoms to diagnosis was a median of 19 days [interquartile range (IQR): 5–43 days]. Confirmed cases were RT-PCR-positive; probable cases had positive Immunoglobulin M (IgM) or Immunoglobulin G (IgG) serology. Participants were followed up at a median of 13.4 months (IQR: 11.3–15.9 months) of diagnosis between 5 March– and 7 November 2024, with a structured, self-administered questionnaire in Spanish. The full patient questionnaire used in this study is available as Supplementary Material. The questionnaire, which was completed in person on paper, elicited data on demographics, travel history and clinical impact, and the cost module covered direct and indirect OOP expenditures since symptom onset. OOP costs were categorized by setting and location. Direct costs included medical consultations and medications, while indirect costs included income loss and nonrefundable travel expenses. Patients’ OOP expenditures covered by health insurance were excluded from calculations. Costs were estimated via self-reports and expressed in 2023 US dollars (USD).5 All the clinics obtained Institutional Review Board approval, and all the data were anonymized.