Self-diagnosis of malaria by travellers: a cohort study on the use of malaria rapid diagnostic tests provided by a Swiss travel clinic.

BACKGROUND: The WHO recommends that all suspect malaria cases be tested before receiving treatment. Rapid diagnostic tests (RDT) for malaria can be performed reliably by community health workers with no formal medical background and thus, RDTs could also be provided to travellers for self-diagnosis during visits to endemic regions. METHODS: RDTs were proposed during pre-travel consultations to pre-defined categories of travellers. A training run on their own blood was performed and, if carried out correctly, the traveller was given a written procedure on how to perform the test and act on its result. The travellers were then proposed to buy a malaria RDT kit and were interviewed upon their return. RESULTS: From February 2012 to February 2017, 744 travellers were proposed RDTs and 692 performed the training run (one could not complete it due to a hand tremor). Among the 691 subjects included, 69% travelled to moderate- or low-risk areas of malaria, 18% to high-risk areas and 13% to mixed-risk areas. The two most frequent categories of travellers to whom RDTs were proposed were long-term travellers (69%) and those travelling to remote areas (57%). 543 travellers (79%) were interviewed upon return. During their trip, 17% (91/543) had a medical problem with fever and 12% (65/543) without fever. Among 91 febrile patients, 57% (52/91) performed an RDT, 22% (20/91) consulted immediately without using the test, and 21% (19/91) did neither. Four RDTs (4/52; 8%) were positive: 2 in low-risk and 2 in high-risk areas (0.7% attack rate of self-documented malaria). Two travellers could not perform the test correctly and attended a facility or took standby emergency treatment. Four travellers with negative results repeated the test after 24 h; all were still negative. Carrying RDTs made travellers feel more secure, especially when travelling with children. CONCLUSIONS: 1/6 travellers experienced fever and 4/5 of those reacted appropriately: more than half used RDTs and a quarter consulted immediately. Four travellers (including 2 from low-risk areas) diagnosed themselves with malaria and self-treated successfully. This strategy allows prompt treatment for malaria in high-risk groups and may avoid over-diagnosis (and subsequent inappropriate treatment) of malaria on-site.

Sentinel surveillance of imported dengue via travellers to Europe 2012 to 2014: TropNet data from the DengueTools Research Initiative.

We describe the epidemiological pattern and genetic characteristics of 242 acute dengue infections imported to Europe by returning travellers from 2012 to 2014. The overall geographical pattern of imported dengue (South-east Asia > Americas > western Pacific region > Africa) remained stable compared with 1999 to 2010. We isolated the majority of dengue virus genotypes and epidemic lineages causing outbreaks and epidemics in Asia, America and Africa during the study period. Travellers acted as sentinels for four unusual dengue outbreaks (Madeira, 2012-13; Luanda, 2013; Dar es Salaam, 2014; Tokyo, 2014). We were able to characterise dengue viruses imported from regions where currently no virological surveillance data are available. Up to 36% of travellers infected with dengue while travelling returned during the acute phase of the infection (up to 7 days after symptom onset) or became symptomatic after returning to Europe, and 58% of the patients with acute dengue infection were viraemic when seeking medical care. Epidemiological and virological data from dengue-infected international travellers can add an important layer to global surveillance efforts. A considerable number of dengue-infected travellers are viraemic after arrival back home, which poses a risk for dengue introduction and autochthonous transmission in European regions where suitable mosquito vectors are prevalent.

Swiss and tropical snakebites: the clinical management. / Morsures de serpents suisses et tropicaux : prise en charge.

With increasing trips to tropical areas, as well as a high number of venomous snake holders in the country, the frequency of snake bites is likely to increase. Even if in 50 % of cases, the bites do not lead to clinical envenoming, rapid and effective management is essential to successful treatment, which includes supply with the polyvalent or specific antivenom and recognition of the signs and symptoms justifying its administration. We will deal here mainly with local and tropical snake envenoming that Swiss practitioners could encounter in their offices or the emergency rooms and propose scenarios according to the syndromes.

Avec l'augmentation des voyages dans les zones tropicales, de même que du nombre de détenteurs de serpents venimeux à domicile, la fréquence des morsures de serpents risque d'augmenter. Même si dans 50 % des cas les morsures ne conduisent pas à une envenimation clinique, une prise en charge rapide et ciblée améliore les chances de succès thérapeutique. Ceci suppose un approvisionnement avec l'antivenin polyvalent ou spécifique et la reconnaissance des signes et des symptômes justifiant son administration. Nous traiterons ici essentiellement des envenimations par des serpents locaux ou tropicaux que le praticien suisse pourrait rencontrer au cabinet ou aux urgences en nous basant sur quelques vignettes et en proposant des scénarios en fonction des syndromes.

Multiplex PCR gastro-intestinal panels for the management of traveller's diarrhea : are they accurate and useful? / Panels gastro-intestinaux par PCR multiplex pour la prise en chargedes diarrhées du voyageur : performants et utiles ?

Until recently, the search for enteropathogens causing travellers' diarrhea was based on stool culture (Campylobacter spp., Salmonella spp. and Shigella spp.), direct microscopy with (Cryptosporidium spp.) or without specific staining (Giardia lamblia, Entamoeba histolytica) or specific antigen detection (Giardia lamblia, Entamoeba histolytica). Molecular analyses are progressively replacing traditional diagnostic methods but their clinical usefulness remains to be better defined. This article attempts to describe the advantages and disadvantages of these new molecular methods and to illustrate situations where they could be useful using clinical cases frequently encountered in the practice of travel medicine.

Jusqu'à présent, la recherche d'entéropathogènes à l'origine de diarrhées au retour de voyage se basait essentiellement sur la culture bactérienne de selles (Campylobacter spp., Salmonella spp. et Shigella spp.), la microscopie directe sans(Giardia lamblia, Entamoeba histolytica) ou avec coloration spéciale (Cryptosporidium spp.) et la recherche d'antigènes spécifiques (Giardia lamblia, Entamoeba histolytica). Désormais, les analyses moléculaires tendent à supplanter les techniques traditionnelles mais l'utilité clinique de la PCR par rapport aux examens conventionnels doit être mieux définie. Cet article cherche à décrire les avantages et les limitations de ces nouvelles méthodes moléculaires et à illustrer des situations dans lesquelles leur utilisation pourrait être indiquée à la lumière de cas cliniques fréquemment rencontrés dans la pratique de la médecine des voyages.

[New approaches of malaria prevention for travelers]. / Nouvelles approches pour la prévention de la malaria chez le voyageur.

Malaria is declining in many tropical countries. This reduction challenges our usual preventive strategies. In moderate to low risk areas, the Swiss guidelines recommend a stand-by emergency treatment. Controversies between experts are numerous though. Professionals at the Travel Clinic in Lausanne has explored shared-decision making through three clinical studies. The first showed that travelers visiting moderate to low risk malaria areas prefer a standby emergency treatment rather than chemoprophylaxis. The second study investigates the use of rapid diagnostic tests by travelers. The third focuses on the prospects of tropical telemedicine. Involving the traveler into the debate is a priority, until a vaccine becomes available.

[Zika virus : from research to vaccine]. / Virus Zika : de la recherche au vaccin.

Zika virus has recently emerged as new teratogenic agent. Research is drastically increasing to allow a better comprehension of the role of this emerging virus in the induction of fetal cerebral anomalies. Several epidemiological and microbiological aspects may explain a higher virulence of the current strain. Various animal models have been developed and confirm the materno-fetal transmission as well as the induction of cerebral development's disorders. In parallel, various companies are working to develop a vaccine and antiviral medicine against Zika virus. Despite promising results, the road remains long until a vaccine or antiviral medicines are available.

Le virus Zika est récemment apparu comme un nouvel agent tératogène. La recherche s'accélère dans le but de mieux comprendre le rôle de ce virus émergent dans la formation de malformations cérébrales chez le fœtus. Plusieurs aspects épidémiologiques et microbiologiques contribuent à la nouvelle virulence observée chez la souche épidémique actuelle. Divers modèles d'infection chez la souris et les primates ont été développés confirmant la transmission transplacentaire du virus et l'induction de troubles du développement cérébral. En parallèle, plusieurs compagnies travaillent au développement d'un vaccin et d'antiviraux contre le virus Zika. Malgré des résultats prometteurs, la route est encore longue avant la mise sur le marché de vaccins ou d'antiviraux pouvant être administrés à la femme enceinte.

Maternal Infection and Adverse Pregnancy Outcomes among Pregnant Travellers: Results of the International Zika Virus in Pregnancy Registry.

In this multicentre cohort study, we evaluated the risks of maternal ZIKV infections and adverse pregnancy outcomes among exposed travellers compared to women living in areas with ZIKV circulation (residents). The risk of maternal infection was lower among travellers compared to residents: 25.0% (n = 36/144) versus 42.9% (n = 309/721); aRR 0.6; 95% CI 0.5-0.8. Risk factors associated with maternal infection among travellers were travelling during the epidemic period (i.e., June 2015 to December 2016) (aOR 29.4; 95% CI 3.7-228.1), travelling to the Caribbean Islands (aOR 3.2; 95% CI 1.2-8.7) and stay duration >2 weeks (aOR 8.7; 95% CI 1.1-71.5). Adverse pregnancy outcomes were observed in 8.3% (n = 3/36) of infected travellers and 12.7% (n = 39/309) of infected residents. Overall, the risk of maternal infections is lower among travellers compared to residents and related to the presence of ongoing outbreaks and stay duration, with stays <2 weeks associated with minimal risk in the absence of ongoing outbreaks.

Safety and immunogenicity of a primary yellow fever vaccination under low-dose methotrexate therapy-a prospective multi-centre pilot study1.

BACKGROUND: More people on immunosuppression live in or wish to travel to yellow fever virus (YFV)-endemic areas. Data on the safety and immunogenicity of yellow fever vaccination (YFVV) during immunosuppression are scarce. The aim of this study was to compare the safety and immunogenicity of a primary YFVV between travellers on methotrexate and controls. METHODS: We conducted a prospective multi-centre controlled observational study from 2015 to 2017 in six Swiss travel clinics. 15 adults (nine with rheumatic diseases, five with dermatologic conditions and one with a gastroenterological disease) on low-dose methotrexate (≤20 mg/week) requiring a primary YFVV and 15 age and sex-matched controls received a YFVV. Solicited/unsolicited adverse reactions were recorded, YFV-RNA was measured in serum samples on Days 3, 7, 10, 14, 28 and neutralizing antibodies on Days 0, 7, 10, 14, 28. RESULTS: Patients´ and controls' median ages were 53 and 52 years; 9 patients and 10 controls were female. 43% of patients and 33% of controls showed local side effects (P = 0.71); 86% of patients and 66% of controls reported systemic reactions (P = 0.39). YFV-RNA was detected in patients and controls on Day 3-10 post-vaccination and was never of clinical significance. Slightly more patients developed YFV-RNAaemia (Day 3: n = 5 vs n = 2, Day 7: n = 9 vs n = 7, Day 10: n = 3 vs n = 2, all P > 0.39). No serious reactions occurred. On Day 10, a minority of vaccinees was seroprotected (patients: n = 2, controls: n = 6). On Day 28, all vaccinees were seroprotected. CONCLUSIONS: First-time YFVV was safe and immunogenic in travellers on low-dose methotrexate. Larger studies are needed to confirm these promising results.

Epidemiology, risk factors and clinical course of SARS-CoV-2 infected patients in a Swiss university hospital: An observational retrospective study.

BACKGROUND: This study aims to describe the epidemiology of COVID-19 patients in a Swiss university hospital. METHODS: This retrospective observational study included all adult patients hospitalized with a laboratory confirmed SARS-CoV-2 infection from March 1 to March 25, 2020. We extracted data from electronic health records. The primary outcome was the need to mechanical ventilation at day 14. We used multivariate logistic regression to identify risk factors for mechanical ventilation. Follow-up was of at least 14 days. RESULTS: 145 patients were included in the multivariate model, of whom 36 (24.8%) needed mechanical ventilation at 14 days. The median time from symptoms onset to mechanical ventilation was 9·5 days (IQR 7.00, 12.75). Multivariable regression showed increased odds of mechanical ventilation with age (OR 1.09 per year, 95% CI 1.03-1.16, p = 0.002), in males (OR 6.99, 95% CI 1.68-29.03, p = 0.007), in patients who presented with a qSOFA score ≥2 (OR 7.24, 95% CI 1.64-32.03, p = 0.009), with bilateral infiltrate (OR 18.92, 3.94-98.23, p<0.001) or with a CRP of 40 mg/l or greater (OR 5.44, 1.18-25.25; p = 0.030) on admission. Patients with more than seven days of symptoms on admission had decreased odds of mechanical ventilation (0.087, 95% CI 0.02-0.38, p = 0.001). CONCLUSIONS: This study gives some insight in the epidemiology and clinical course of patients admitted in a European tertiary hospital with SARS-CoV-2 infection. Age, male sex, high qSOFA score, CRP of 40 mg/l or greater and a bilateral radiological infiltrate could help clinicians identify patients at high risk for mechanical ventilation.

Telemedicine for health issues while abroad: interest and willingness to pay among travellers prior to departure.

Background: Telemedicine is emerging as a useful tool to provide expert medical advice to individuals facing health issues while travelling in remote areas. Before embarking on the development of a telemedicine system, we conducted a survey to assess the needs and expectations of travellers for such a service, and evaluate opinions about the importance of various travel criteria that may determine the contract of such insurance. Objectives: (i) To assess whether a telemedicine service is considered useful by travellers, (ii) to investigate which telecommunication medium is preferred, (iii) to determine which subgroup of travellers would be most interested in this service and (iv) to estimate the amount of money travellers would be willing to pay for a telemedicine service. Methods: Travellers coming to our clinic for pre-travel advice were given a questionnaire to be filled in before consultation. The questionnaire focused on demographics, travel details, health status, interest and willingness to pay for a telemedicine service. Results: Among 307 returned questionnaires, 59% of travellers were interested in a telemedicine service. Email was the preferred communication medium for 63%, mobile phone for 46% and video calls for 31% individuals (multiple answers). Travellers aged ≥60 years and those with an immunocompromising condition tended to be more interested in telemedicine (respectively OR = 1.65; 95% CI: 0.75-3.62 and OR = 3.56; 95% CI: 0.41-30.95). The 99% of travellers were willing to pay for such a service. Median price was 50 USD (IQR: 30-50 USD). There was no correlation between travel duration and amount to be paid. Conclusion: Among individuals consulting for pre-travel advice at a specialized clinic, there is considerable interest in telemedicine, particularly among older and immunocompromised travellers. Based on these data, a pilot system using email communication to help travellers confronted with health issues while abroad was developed and implemented in our travel clinic.

Malaria prevention strategies and recommendations, from chemoprophylaxis to stand-by emergency treatment: a 10-year prospective study in a Swiss Travel Clinic.

BACKGROUND: There are several possible malaria prevention strategies for travellers. In Switzerland, chemoprophylaxis (CP) is recommended for persons visiting areas highly endemic for malaria and stand-by emergency treatment (SBET) for areas with moderate to low risk. OBJECTIVE: To describe the type of malaria prevention prescribed to travel clinic attendees with a specific focus on changes over time following adaptation of recommendations. METHODS: All pre-travel first consultation data recorded between November 2002 and December 2012 were included. Country-specific malaria preventive recommendations provided and medicines prescribed over time were analysed. RESULTS: In total, 64 858 client-trips were recorded. 91% of travellers planned to visit a malaria endemic country. Among those clients, 42% were prescribed an antimalarial medicine as CP only, 36% as SBET only, and 3% both. Between 2002 and 2012, there was a 16% drop of CP prescription ( P < 0.001) and a 21% increase of SBET prescription ( P < 0.001). Among travellers receiving CP, the proportion of those prescribed mefloquine dropped from 82% in 2002 to 46% in 2012 while those prescribed atovaquone-proguanil (AP) increased from 7% to 39%. For those prescribed SBET, the proportion dropped from 46% to 30% for AP and increased from 2% to 61% for artemether-lumefantrine. CP prescription for travellers to India fell from 62% to 5% and SBET prescription increased from 40% to 88% after the change of recommendation from CP to SBET in 2005 for this country. Comparatively, CP prescription for travellers to Senegal, for which no change of recommendation occurred, remained relatively stable between 88% in 2002 and 89% in 2012. CONCLUSION: This study shows the considerable decline of antimalarial prescription for chemoprophylaxis that occurred over the 10-year period in favour of SBET.

Schistosomiasis in European Travelers and Migrants: Analysis of 14 Years TropNet Surveillance Data.

Schistosomiasis remains one of the most prevalent parasitic diseases worldwide and the infection is frequently found in travelers and migrants. The European Network for Tropical Medicine and Travel Health conducted a sentinel surveillance study on imported schistosomiasis between 1997 and 2010. This report summarizes epidemiological and clinical data from 1,465 cases of imported schistosomiasis. Direct pathogen detection and serology were the main diagnostic tools applied. Of these, 486 (33%) cases were identified among European travelers, 231 (16%) among long-term expatriates, and 748 (51%) among non-European immigrants. Overall, only 18.6% of travelers had received pretravel advice; 95% of infections were acquired in the African region. On species level, Schistosoma mansoni was identified in 570 (39%) and Schistosoma haematobium in 318 (22%) cases; 57.5% of patients were symptomatic. Acute symptoms were reported in 27% of patients leading to earlier presentation within 3 months. Praziquantel was used in all patients to treat schistosomiasis. Many infections were detected in asymptomatic patients. In 47.4% of asymptomatic patients infection was detected by microscopy and in 39% by serology or antigen testing. Schistosomiasis remains a frequent infection in travelers and migrants to Europe. Travelers should be made aware of the risk of schistosomiasis infection when traveling to sub-Saharan Africa. Posttravel consultations particularly for returning expatriates are useful given the high potential for detecting asymptomatic infections.

Travellers' profile, travel patterns and vaccine practices--a 10-year prospective study in a Swiss Travel Clinic.

BACKGROUND: The travel clinic in Lausanne serves a catchment area of 700 000 of inhabitants and provides pre- and post-travel consultations. This study describes the profile of attendees before departure, their travel patterns and the travel clinic practices in terms of vaccination over time. METHODS: We included all pre-travel first consultation data recorded between November 2002 and December 2012 by a custom-made program DIAMM/G. We analysed client profiles, travel characteristics and vaccinations prescribed over time. RESULTS: Sixty-five thousand and forty-six client-trips were recorded. Fifty-one percent clients were female. Mean age was 32 years. In total, 0.1% were aged <1 year and 0.2% ≥80 years. Forty-six percent of travellers had pre-existing medical conditions. Forty-six percent were travelling to Africa, 35% to Asia, 20% to Latin America and 1% (each) to Oceania and Europe; 19% visited more than one country. India was the most common destination (9.6% of travellers) followed by Thailand (8.6%) and Kenya (6.4%). Seventy-three percent of travellers were planning to travel for ≤ 4 weeks. The main reasons for travel were tourism (75%) and visiting friends and relatives (18%). Sixteen percent were backpackers. Pre-travel advice were sought a median of 29 days before departure. Ninety-nine percent received vaccine(s). The most frequently administered vaccines were hepatitis A (53%), tetanus-diphtheria (46%), yellow fever (39%), poliomyelitis (38%) and typhoid fever (30%). CONCLUSIONS: The profile of travel clinic attendees was younger than the general Swiss population. A significant proportion of travellers received vaccinations that are recommended in the routine national programme. These findings highlight the important role of travel clinics to (i) take care of an age group that has little contact with general practitioners and (ii) update vaccination status. The most commonly prescribed travel-related vaccines were for hepatitis A and yellow fever. The question remains to know whether clients do attend travel clinics because of compulsory vaccinations or because of real travel health concern or both.

Acute schistosomiasis: a risk underestimated by travelers and a diagnosis frequently missed by general practitioners-a cluster analysis of 42 travelers.

BACKGROUND: In 2011, a patient was admitted to our hospital with acute schistosomiasis after having returned from Madagascar and having bathed at the Lily waterfalls. On the basis of this patient's indication, infection was suspected in 41 other subjects. This study investigated (1) the knowledge of the travelers about the risks of schistosomiasis and their related behavior to evaluate the appropriateness of prevention messages and (2) the diagnostic workup of symptomatic travelers by general practitioners to evaluate medical care of travelers with a history of freshwater exposure in tropical areas. METHODS: A questionnaire was sent to the 42 travelers with potential exposure to schistosomiasis. It focused on pre-travel knowledge of the disease, bathing conditions, clinical presentation, first suspected diagnosis, and treatment. RESULTS: Of the 42 questionnaires, 40 (95%) were returned, among which 37 travelers (92%) reported an exposure to freshwater, and 18 (45%) were aware of the risk of schistosomiasis. Among these latter subjects, 16 (89%) still reported an exposure to freshwater. Serology was positive in 28 (78%) of 36 exposed subjects at least 3 months after exposure. Of the 28 infected travelers, 23 (82%) exhibited symptoms and 16 (70%) consulted their general practitioner before the information about the outbreak had spread, but none of these patients had a serology for schistosomiasis done during the first consultation. CONCLUSIONS: The usual prevention message of avoiding freshwater contact when traveling in tropical regions had no impact on the behavior of these travelers, who still went swimming at the Lily waterfalls. This prevention message should, therefore, be either modified or abandoned. The clinical presentation of acute schistosomiasis is often misleading. General practitioners should at least request an eosinophil count, when confronted with a returning traveler with fever. If eosinophilia is detected, it should prompt the search for a parasitic disease.