Vaccination against dengue fever for travellers.

Dengue fever, endemic to most tropical and subtropical countries, is a major cause of illness in travellers, but severe dengue, hospitalisation and death are considered rare in this population. Two vaccines against dengue fever, Dengvaxia® and Qdenga®, are available. While there is no recommendation for the use of Dengvaxia® in travellers, Qdenga® has been licensed for travellers in many European countries since December 2022, most recently (29 July 2024) in Switzerland by Swissmedic. The Swiss Expert Committee for Travel Medicine (ECTM), having assessed available data on the Qdenga® vaccine, issues the following recommendations: (1) Vaccination against dengue fever virus with Qdenga® is not recommended for persons with no previous dengue fever infection. (2) Vaccination with Qdenga® may be recommended for travellers aged 6 years and older who have evidence of previous dengue infection, defined as (a) a laboratory-confirmed dengue infection (PCR, antigen or seroconversion) or (b) a compatible history of dengue infection with a positive IgG serological test AND expected exposure to a region with significant dengue transmission. Travel medicine advisors should provide clear information in accessible language on the complexity of dengue vaccines and the risk/benefit evaluation for their use in travellers.

Mpox virus infection in women and outbreak sex disparities: A Systematic Review and Meta-analysis.

BACKGROUND: Although the recent literature indicates that mpox (monkeypox) primarily affects men, there are also multiple reports in women. Estimates of the sex distribution of mpox patients and patterns will enable a better understanding of the ongoing mpox outbreak. METHODS: In this systematic review and meta-analysis, seven databases were searched for studies published in English up to January 4th, 2023. The proportion of women with mpox was the primary outcome. A random-effects model was fitted for the primary outcome, and a sensitivity analysis was performed to check possible outliers in the studies. RESULTS: Here we screened 470 articles and included 60 studies for qualitative synthesis. 42 studies with 3125 women out of 47,407 confirmed cases were found suitable for meta-analysis. The pooled proportion of female patients is 17.22% (95% CI: 10.49-25.11; I2 = 98.86%). Subgroup analyses reveal higher proportion before 2022 [44.09% (42.93-46.86] than 2022 onwards [2.40% (1.17-3.98)], and in endemic countries [43.13% (37.63-48.72)] than in nonendemic countries [6.15% (2.20-11.65)]. CONCLUSIONS: There is considerable caseload (17.22%) amongst women, which must be seen in the context of a much higher proportion (44.09%) in studies prior to 2022 compared to 2.40% in the 2022 outbreak indicating an epidemiological shift. Data on disease characteristics among women with mpox disease are scarce. Further studies should focus on these aspects to better understand the disease in women and empower epidemiologists and clinicians to make evidence-based decisions for this vulnerable group.

Mpox (formerly known as monkeypox) is an infection caused by the monkeypox virus. While it is known to affect men more commonly than women, there are also reports of this infection in women. We have searched the literature to find out how frequently mpox affected women. We found that 17% of mpox patients were female. However, this number was 44% before 2022, and has reduced to 2% from 2022 onwards. This indicates changes in mpox disease characteristics and in the ability to infect different sexes. Further studies are needed to better understand the disease in women and empower epidemiologists and clinicians to make evidence-based decisions for this group.

Surveillance of global, travel-related illness using a novel app: a multivariable, cross-sectional study.

INTRODUCTION: Current traveller health surveillance is 'top-down'. Mobile-based surveillance could capture infection symptoms in real time. We aimed to evaluate the spectrum of illness in travellers using a mobile app-based system. METHODS: This study (ClinicalTrials.gov NCT04672577) used an application called Infection Tracking in Travellers (ITIT) that records travel-related illness symptoms with associated geolocation and weather data. The free ITIT app is available in 14 languages. Participants were recruited globally from April 2022 to July 2023. Participants >18 years of age travelled internationally and provided electronic consent. Incentives included the provision of travel health information imported from the WHO website. Symptoms were recorded with daily pop-up questionnaires and symptom severity was assessed using a Likert scale. Two post-travel questionnaires were administered. Logistic mixed models examined factors relating to symptom presence, and a random forest model examined symptom impact. RESULTS: 609 participants were recruited until July 2023. Participants had an average age of 37 years (18-79), and an average travel duration of 26 days (2-281). Most participants were travelling for leisure/tourism (401; 66%), followed by 'visiting friends and relatives' (99; 16%) and business travel (80; 13%). All continents were visited by at least one traveller. Of 470 registered trips, symptoms were reported on 163 trips (35%). Gastrointestinal symptoms were reported on 87 trips (19%) and respiratory symptoms on 81 trips (17%). The most important factors in predicting the presence of symptoms were duration of travel, travelling in winter and high humidity. Diarrhoea, headache and nausea were symptoms with most impact on daily activities. Post-travel questionnaires showed that 12% of surveyed participants experienced symptoms with several episodes of self-treatment. Two diagnoses were recorded: Lyme disease and amoebic dysentery. CONCLUSION: The digital tool ITIT successfully captures the spectrum of travel-related illness. This detailed epidemiology is crucial for outbreak detection and for the formulation of travel medicine guidelines. TRIAL REGISTRATION NUMBER: NCT04672577.

A meta-analysis and mapping of global mpox infection among children and adolescents.

Monkeypox (mpox) is a significant health concern affecting children and adolescents globally. This systematic review and meta-analysis aims to synthesise the available evidence on the proportion of children and adolescents affected by the mpox virus. A comprehensive search was conducted in seven electronic databases (PubMed, Scopus, Web of Science, EMBASE, ProQuest, EBSCOHost, and Cochrane) to identify the original reports on mpox cases in children and adolescents till 15 January 2023. Descriptive reports on probable or laboratory-confirmed mpox in children and adolescents (0-17 years old) were considered eligible. Studies not providing separate data for the above age group and case-control studies were excluded. The primary outcome was pooled proportion of mpox cases among children and adolescents. Proportion meta-analysis and heterogeneity between studies were determined using a restricted maximum likelihood estimator, and a random-effects model was fitted to the data. Sensitivity analysis and subgroup analysis were also conducted. A drapery plot was also provided as a complementary figure to the forest plot. The protocol was prospectively registered with PROSPERO (CRD42023392475). A total of 440 studies were identified, of which 37 were included in the review and 25 in the meta-analysis (62,701 participants with 3306 children and adolescents). The pooled proportion of children and adolescents was 0.46 (95% CI: 0.30-0.63, I2 :100%). The proportion of children and adolescents was significantly lower (p < 0.001) in the ongoing pandemic 0.04 (95% CI: 0.00-0.32) than before 2022 0.62 (95% CI: 0.49-0.74). The meta-regression showed that the higher the study's sample size, the lower the proportion of children among the mpox cases. Both overall and subgroup heterogeneity were high. Adolescents and children below 5 years are commonly affected by the ongoing pandemic. In conclusion, the high proportion of children affected by the mpox virus highlights the need for increased research and targeted interventions to prevent and control the spread of the virus in this population.

Travel-related respiratory symptoms and infections in travellers (2000-22): a systematic review and meta-analysis.

BACKGROUND: Respiratory tract infections (RTIs) are common in travellers due to the year-round or seasonal presence of respiratory pathogen and exposure to crowded environments during the itinerary. No study has systematically examined the burden of RTI infections among travellers. The aim of this systematic review and meta-analysis is to evaluate the prevalence of RTIs and symptoms suggestive of RTIs among travellers according to risk groups and/or geographic region, and to describe the spectrum of RTIs. METHODS: The systematic review and meta-analysis was registered in PROSPERO (CRD42022311261). We searched Medline, Embase, Scopus, Cochrane Central, Web of Science, Science Direct and preprint servers MedRxiv, BioRxiv, SSRN and IEEE Xplore on 1 February 2022. Studies reporting RTIs or symptoms suggestive of RTIs in international travellers after 1 January 2000 were eligible. Data appraisal and extraction were performed by two authors, and proportional meta-analyses were used to obtain estimates of the prevalence of respiratory symptoms and RTIs in travellers and predefined risk groups. FINDINGS: A total of 429 articles on travellers' illness were included. Included studies reported 86 841 symptoms suggestive of RTIs and 807 632 confirmed RTIs. Seventy-eight percent of reported respiratory symptoms and 60% of RTIs with available location data were acquired at mass gatherings events. Cough was the most common symptom suggestive of respiratory infections, and the upper respiratory tract was the most common site for RTIs in travellers. The prevalence of RTIs and respiratory symptoms suggestive of RTIs were 10% [8%; 14%] and 37% [27%; 48%], respectively, among travellers. Reporting of RTIs in travellers denoted by publication output was found to correlate with global waves of new respiratory infections. INTERPRETATION: This study demonstrates a high burden of RTIs among travellers and indicates that travellers' RTIs reflect respiratory infection outbreaks. These findings have important implications for understanding and managing RTIs among travellers.

[Rising temperatures and the threat of malaria in Europe: an unwelcome return?] / Augmentation des températures et menace du paludisme en Europe : un retour indésirable ?

Rising temperatures pose a threat to malaria transmission in Europe. Anopheles vectors are becoming more stable and widespread, putting some areas at increased risk of transmission for extended periods. By 2030 or 2050, the period of susceptibility is expected to extend to 3-6 months in some European countries and Anopheles mosquitoes are expected to migrate northward. In addition, climate change has led to a substantial increase in the number of climate refugees in Europe, increasing the risk of spread of the disease from endemic areas to susceptible regions. Urgent action is needed to prevent the transmission of malaria and other climate change-related diseases in Europe.

L'augmentation des températures représente une menace pour la transmission du paludisme en Europe. Les vecteurs Anopheles deviennent plus stables et répandus, exposant certaines régions à un risque accru de transmission pendant des périodes prolongées. D'ici 2030 ou 2050, la période de réceptivité devrait s'étendre à 3-6 mois dans certains pays européens, avec une migration des moustiques Anopheles vers le nord. En outre, le changement climatique a entraîné une augmentation significative du nombre de réfugiés climatiques en Europe, augmentant ainsi le risque de propagation de maladies des zones endémiques vers des régions réceptives. Il est impératif d'agir rapidement pour prévenir la transmission du paludisme et d'autres maladies liées au changement climatique en Europe.

Spotted fever group rickettsiae and Anaplasma phagocytophilum in Borrelia burgdorferi sensu lato seropositive individuals with or without Lyme disease: A retrospective analysis.

Background: The Ixodes ricinus tick is the main vector of Borrelia burgdorferi and tick-borne encephalitis virus in Switzerland. Spotted fever group Rickettsiae (SFG) and Anaplasma phagocytophilum have been detected in Swiss ticks, however, information about the extent and clinical presentation of these infections in humans is scant. Methods: Indirect fluorescent antibody tests for SFG rickettsiae and Anaplasma phagocytophilum were performed on serum samples of 121 Borrelia burgdorferi seropositive patients with and without Lyme disease and 43 negative controls. Results: Out of 121 Borrelia burgdorferi seropositive individuals, 65 (53.7%) were seropositive for IgG and 15 (12.4%) for IgM antibodies to SFG rickettsiae. IgM antibodies were detected more frequently in early-than in late-stage of Lyme disease (12 out of 51 and 2 out of 49; respectively; p â€‹= â€‹0.0078). Significantly higher IgG antibody titers against SFG rickettsiae were found in patients with late-stage compared to patients with early-stage Lyme disease (mean titer 1:261 and 1:129, respectively; p â€‹= â€‹0.038). This difference was even more pronounced in patients with acrodermatitis chronica atrophicans compared to patients with early stage of Lyme disease (mean titer 1:337 and 1:129, respectively; p â€‹= â€‹0.009).In patients presenting with fatigue, headache and myalgia, the prevalence of IgG antibodies against SFG rickettsiae was significantly higher (7 out of 11; 63.6%) than in Borrelia burgdorferi seropositive individuals without clinical illness (1 out of 10; 10%; p â€‹= â€‹0.024). IgG antibodies to Anaplasma phagocytophilum were detected in 12 out of 121 individuals (9.9%), no IgM antibodies were found. Conclusion: Infections with SFG rickettsiae and Anaplasma phagocytophilum are underdiagnosed and should be ruled out after a tick bite. Further studies are needed to elucidate the possible causative role of SFG rickettsiae for myalgia, headache and long-lasting fatigue after a tick bite and to determine the necessity for an antibiotic treatment.

Hair concentrations of anti-malarials in returned travellers-the HAIR study: Proof of principle analysis.

BACKGROUND: Hair analysis to identify substance use is an established methodology. This could also be a method to monitor adherence to antimalarial drugs. We aimed to establish a methodology to determine hair concentrations of atovaquone, proguanil and mefloquine in travellers using chemoprophylaxis. METHODS: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous analysis of the antimalarial drugs -atovaquone (ATQ), proguanil (PRO) and mefloquine (MQ), in human hair. The hair samples from five volunteers were used for this proof-of-concept analysis. Three volunteers were taking daily atovaquone/proguanil (ATQ/PRO) chemoprophylaxis and two volunteers were using weekly mefloquine (MQ) chemoprophylaxis. RESULTS: With this proof-of-principle analysis, we could show that ATQ/PRO and MQ are integrated into the hair matrix. Chemoprophylaxis could be quantified with the established method. In hair segments, maximal concentrations of 3.0 ng/mL/20 mg hair proguanil, 1.3 ng/mL/20 mg hair atovaquone and 78.3 ng/mL/20 mg hair mefloquine were measured. Moreover, malaria drug concentration changes correlated with the time interval since finishing the chemoprophylaxis regimen. CONCLUSIONS: The validated method was used successfully for the analysis of antimalarial-drug positive hair samples containing atovaquone, proguanil or mefloquine. This research shows that hair can be used for adherence monitoring of chemoprophylaxis and paves the way for larger studies and optimized procedures.

COVID-19 impact on EuroTravNet infectious diseases sentinel surveillance in Europe.

BACKGROUND: The COVID-19 pandemic resulted in a sharp decline of post-travel patient encounters at the European sentinel surveillance network (EuroTravNet) of travellers' health. We report on the impact of COVID-19 on travel-related infectious diseases as recorded by EuroTravNet clinics. METHODS: Travelers who presented between January 1, 2019 and September 30, 2021 were included. Comparisons were made between the pre-pandemic period (14 months from January 1, 2019 to February 29, 2020); and the pandemic period (19 months from March 1, 2020 to September 30, 2021). RESULTS: Of the 15,124 visits to the network during the 33-month observation period, 10,941 (72%) were during the pre-pandemic period, and 4183 (28%) during the pandemic period. Average monthly visits declined from 782/month (pre-COVID-19 era) to 220/month (COVID-19 pandemic era). Among non-migrants, the top-10 countries of exposure changed after onset of the COVID-19 pandemic; destinations such as Italy and Austria, where COVID-19 exposure peaked in the first months, replaced typical travel destinations in Asia (Thailand, Indonesia, India). There was a small decline in migrant patients reported, with little change in the top countries of exposure (Bolivia, Mali). The three top diagnoses with the largest overall decreases in relative frequency were acute gastroenteritis (-5.3%), rabies post-exposure prophylaxis (-2.8%), and dengue (-2.6%). Apart from COVID-19 (which rose from 0.1% to 12.7%), the three top diagnoses with the largest overall relative frequency increase were schistosomiasis (+4.9%), strongyloidiasis (+2.7%), and latent tuberculosis (+2.4%). CONCLUSIONS: A marked COVID-19 pandemic-induced decline in global travel activities is reflected in reduced travel-related infectious diseases sentinel surveillance reporting.

Analysis of Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA) Parameters in Young Adults after SARS-CoV-2 Infection (COVID-19) Compared with Healthy Young Controls.

PURPOSE: To compare retinal changes in young adults with previous SARS-CoV-2 infection with healthy young controls using optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). METHODS: This prospective single-center study was conducted at the University Hospital of Zurich, Zurich, Switzerland. Participants were imaged from May to November 2021 using the SOLIX device (Visionix International SAS, Pont-de-l'Arche, France). We performed 12 mm × 12 mm, 6.4 mm × 6.4 mm, 6 mm × 6 mm and 3 mm × 3 mm OCT and OCTA scans, as well as fundus photography of each participant's eyes. RESULTS: In total, 466 participants were imaged. Of these, 233 were healthy controls with negative RT-PCR tests for SARS-CoV-2, 168 were young adults who had a SARS-CoV-2 infection at least 180 days previously, 19 were participants who had a SARS-CoV-2 infection < 180 days previously, and 46 were participants with asymptomatic SARS-CoV-2 infection (i.e., serologically positive but with no symptoms). Compared with healthy controls, statistically significant differences were found for OCTA recordings of the optic disc for the whole image (WI) and WI capillary vessel density, with both being higher in the SARS-CoV-2 group. CONCLUSION: Statistically significant results were only observed for selected variables, and in parts, only unilaterally, with relatively large p values (p = 0.02-0.03). Thus, we did not interpret these as clinically significant, leading to the conclusion that young and otherwise healthy individuals (mainly men) seem to recover from mild COVID-19 infections with no ophthalmological residues.