Clinical Characteristics and Outcomes Among Travelers With Severe Dengue : A GeoSentinel Analysis.

BACKGROUND: Dengue virus is a flavivirus transmitted by Aedes mosquitoes and is an important cause of illness worldwide. Data on the severity of travel-associated dengue illness are limited. OBJECTIVE: To describe the epidemiology, clinical characteristics, and outcomes among international travelers with severe dengue or dengue with warning signs as defined by the 2009 World Health Organization classification (that is, complicated dengue). DESIGN: Retrospective chart review and analysis of travelers with complicated dengue reported to GeoSentinel from January 2007 through July 2022. SETTING: 20 of 71 international GeoSentinel sites. PATIENTS: Returning travelers with complicated dengue. MEASUREMENTS: Routinely collected surveillance data plus chart review with abstraction of clinical information using predefined grading criteria to characterize the manifestations of complicated dengue. RESULTS: Of 5958 patients with dengue, 95 (2%) had complicated dengue. Eighty-six (91%) patients had a supplemental questionnaire completed. Eighty-five of 86 (99%) patients had warning signs, and 27 (31%) were classified as severe. Median age was 34 years (range, 8 to 91 years); 48 (56%) were female. Patients acquired dengue most frequently in the Caribbean (n = 27 [31%]) and Southeast Asia (n = 21 [24%]). Frequent reasons for travel were tourism (46%) and visiting friends and relatives (32%). Twenty-one of 84 (25%) patients had comorbidities. Seventy-eight (91%) patients were hospitalized. One patient died of nondengue-related illnesses. Common laboratory findings and signs were thrombocytopenia (78%), elevated aminotransferase (62%), bleeding (52%), and plasma leakage (20%). Among severe cases, ophthalmologic pathology (n = 3), severe liver disease (n = 3), myocarditis (n = 2), and neurologic symptoms (n = 2) were reported. Of 44 patients with serologic data, 32 confirmed cases were classified as primary dengue (IgM+/IgG-) and 12 as secondary (IgM-/IgG+) dengue. LIMITATIONS: Data for some variables could not be retrieved by chart review for some patients. The generalizability of our observations may be limited. CONCLUSION: Complicated dengue is relatively rare in travelers. Clinicians should monitor patients with dengue closely for warning signs that may indicate progression to severe disease. Risk factors for developing complications of dengue in travelers need further prospective study. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention, International Society of Travel Medicine, Public Health Agency of Canada, and GeoSentinel Foundation.

Intestinal protozoa in returning travellers: a GeoSentinel analysis from 2007 to 2019.

BACKGROUND: Prolonged diarrhoea is common amongst returning travellers and is often caused by intestinal protozoa. However, the epidemiology of travel-associated illness caused by protozoal pathogens is not well described. METHODS: We analysed records of returning international travellers with illness caused by Giardia duodenalis, Cryptosporidium spp., Cyclospora cayetanensis or Cystoisospora belli, reported to the GeoSentinel Network during January 2007-December 2019. We excluded records of travellers migrating, with an unascertainable exposure country, or from GeoSentinel sites that were not located in high-income countries. RESULTS: There were 2517 cases, 82.3% giardiasis (n = 2072), 11.4% cryptosporidiosis (n = 287), 6.0% cyclosporiasis (n = 150) and 0.3% cystoisosporiasis (n = 8). Overall, most travellers were tourists (64.4%) on long trips (median durations: 18-30 days). Cryptosporidiosis more frequently affected people < 18 years (13.9%) and cyclosporiasis affected people ≥ 40 years (59.4%). Giardiasis was most frequently acquired in South Central Asia (45.8%) and sub-Saharan Africa (22.6%), cryptosporidiosis in sub-Saharan Africa (24.7%) and South-Central Asia (19.5%), cyclosporiasis in South East Asia (31.3%) and Central America (27.3%), and cystoisosporiasis in sub-Saharan Africa (62.5%). Cyclosporiasis cases were reported from countries of uncertain endemicity (e.g. Cambodia) or in countries with no previous evidence of this parasite (e.g. French Guiana). The time from symptom onset to presentation at a GeoSentinel site was the longest amongst travellers with giardiasis (median: 30 days). Over 14% of travellers with cryptosporidiosis were hospitalized. CONCLUSIONS: This analysis provides new insights into the epidemiology and clinical significance of four intestinal protozoa that can cause morbidity in international travellers. These data might help optimize pretravel advice and post-travel management of patients with travel-associated prolonged gastrointestinal illnesses. This analysis reinforces the importance of international travel-related surveillance to identify sentinel cases and areas where protozoal infections might be undetected or underreported.