Severe Dengue Virus Infection in Travelers: Risk Factors and Laboratory Indicators

Background. Dengue fever is the most common arboviral disease in travelers. In countries where dengue virus is endemic, sequential (secondary) infections with different dengue virus serotypes are associated with disease severity. Data on severity and secondary infection rates in a population of travelers are lacking. Methods. Intensified surveillance of dengue fever in travelers was performed within the European Network on Surveillance of Imported Infectious Diseases. Data were collected at 14 European clinical referral centers between 2003 and 2005. Results. A total of 219 dengue virus infections imported from various regions of endemicity were reported. Serological analysis revealed a secondary immune response in 17%. Spontaneous bleeding was observed in 17 (8%) patients and was associated with increased serum alanine and aspartate aminotransferase levels and lower median platelet counts. Two (0.9%) patients fulfilled the World Health Organization (WHO) case definition for dengue hemorrhagic fever. However, 23 (11%) travelers had severe clinical manifestations (internal hemorrhage, plasma leakage, shock, or marked thrombocytopenia). A secondary immune response was significantly associated with both spontaneous bleeding and other severe clinical manifestations. Conclusions. In travelers, severe dengue virus infections are not uncommon but may be missed if the WHO classification is strictly applied. High liver enzyme levels and low platelet counts could serve as indicators of disease severit

The incidence of malaria in travellers to South-East Asia: is local malaria transmission a useful risk indicator?

Peer reviewe

Travelers' health problems and behavior : prospective study with post-travel follow-up

Background: The annual number of international tourist arrivals has recently exceeded one billion, yet surprisingly few studies have characterized travelers' behavior, illness, and risk factors in a prospective setting. Particularly scarce are surveys of data spanning travel, return, and follow-up of the same cohort. This study examines behavior and illness among travelers while abroad, after return home, and at follow-up. Patterns of behavior connected to type of travel and illness are characterized so as to identify risk factors and provide background data for pre-travel advice. Methods: Volunteers to this prospective cohort study were recruited at visits to a travel clinic prior to departure. Data on the subjects' health and behavior were collected by questionnaires before and after journeys and over a three-week follow-up. In addition, the subjects were asked to fill in health diaries while traveling. Results: The final study population consisted of 460 subjects, 79 % of whom reported illness during travel or on arrival: 69 % had travelers' diarrhea (TD), 17 % skin problems, 17 % fever, 12 % vomiting, 8 % respiratory tract infection, 4 % urinary tract infection, 2 % ear infection, 4 % gastrointestinal complaints other than TD or vomiting, and 4 % other symptoms. Of all subjects, 10 % consulted a doctor and 0.7 % were hospitalized; 18 % took antimicrobials, with TD as the most common indication (64 %). Ongoing symptoms were reported by 25 % of all travelers upon return home. During the three-week follow-up (return rate 51 %), 32 % of respondents developed new-onset symptoms, 20 % visited a doctor and 1.7 % were hospitalized. Factors predisposing to health problems were identified by multivariable analysis: certain regions (Southern Asia, South-Eastern Asia, and Eastern Africa), female gender, young age, and long travel duration. Conclusions: Despite proper preventive measures like vaccinations, malaria prophylaxis, and travel advice, the majority of our subjects fell ill during or after travel. As the symptoms mostly remained mild, health care services were seldom needed. Typical traveler profiles were identified, thereby providing a tool for pre-travel advice. The finding that one third reported new-onset illness during follow-up attests to the importance of advising clients on potential post-travel health problems already during pre-travel visits.Peer reviewe

Infection control in the management of highly pathogenic infectious diseases: consensus of the European Network of Infectious Disease

The European Network for Infectious Diseases (EUNID) is a network of clinicians, public health epidemiologists, microbiologists, infection control, and critical-care doctors from the European member states, who are experienced in the management of patients with highly infectious diseases. We aim to develop a consensus recommendation for infection control during clinical management and invasive procedures in such patients. After an extensive literature review, draft recommendations were amended jointly by 27 partners from 15 European countries. Recommendations include repetitive training of staff to ascertain infection control, systematic use of cough and respiratory etiquette at admission to the emergency department, fluid sampling in the isolation room, and analyses in biosafety level 3/4 laboratories, and preference for point-of-care bedside laboratory tests. Children should be cared for by paediatricians and intensive-care patients should be cared for by critical-care doctors in high-level isolation units (HLIU). Invasive procedures should be avoided if unnecessary or done in the HLIU, as should chest radiography, ultrasonography, and renal dialysis. Procedures that require transport of patients out of the HLIU should be done during designated sessions or hours in secure transport. Picture archiving and communication systems should be used. Post-mortem examination should be avoided; biopsy or blood collection is preferred