Business travel-associated illness: a GeoSentinel analysis

Seroprevalence of dengue, Japanese encephalitis and Zika among long-term expatriates in Thailand

BACKGROUND

Travel to Southeast Asia increases the likelihood of acquiring mosquito-borne Flavivirus infections such as dengue (DENV), Japanese encephalitis (JEV) and Zika viruses (ZIKV). Expatriates are long-term travellers who have a higher risk of mosquito-borne illness at their destination country. The purpose of this study was to evaluate the seroprevalence of DENV, JEV and ZIKV infections and the determinants contributing to seropositivity among expatriates living in Thailand.

METHODS

A cross-sectional study was performed from December 2017 to February 2020. Expatriates from non-Flavivirus endemic countries were recruited. 5 mL of blood was collected for DENV 1-4, JEV and ZIKV antibody testing by plaque reduction neutralization test (PRNT50). Individuals with vaccination histories or diagnoses for dengue, Japanese encephalitis, yellow fever and tick-borne encephalitis were excluded.

RESULTS

Among 254 participants, most participants (83.1%) were male, the mean age was 65 years and the median duration of stay in Thailand was 6 years. Seroprevalence rate of any Flavivirus, non-specific DENV, DENV1-4, JEV and ZIKV were 34.3, 30.7, 20.5, 18.1, 18.9, 10.6, 4.7 and 2.8%, respectively. The presence of neutralizing antibodies against DENV1-4 positively correlates with the duration of stay in Thailand. DENV seropositivity was associated with living in urban areas (aOR 2.75, 95% CI 1.36-5.57). Expatriates were unlikely to have detectable anti-JEV antibodies regardless of time spent in a JEV-endemic area. No risk factors were identified that were significantly associated with JEV or ZIKV seropositivity. Only 48.4% received pre-travel counselling services, while only 18.9% visited a travel medicine specialist.

CONCLUSIONS

A high proportion (34.3%) of long-term expatriates living in Thailand were seropositive for flavivirus, mainly from dengue (30.7%). To minimize risk, travel medicine practitioners should provide adequate pre-travel health risk information on mosquito-borne flavivirus infection and offer advice on mosquito bite prevention strategies. Dengue vaccine might be considered in high-risk travellers such as long-term expatriate.

Travel vaccines-priorities determined by incidence and impact

BACKGROUND

Infectious disease epidemiology is continuously shifting. While travel has been disrupted by the COVID-19 pandemic and travel-related epidemiological research experienced a pause, further shifts in vaccine-preventable diseases (VPDs) relevant for travellers have occurred.

METHODS

We conducted a literature search on the epidemiology of travel-related VPD and synthesized data for each disease with a focus on symptomatic cases and on the impact of the respective infection among travellers, considering the hospitalization rate, disease sequela and case fatality rate. We present new data and revised best estimates on the burden of VPD relevant for decisions on priorities in travel vaccines.

RESULTS

COVID-19 has emerged to be a top travel-related risk and influenza remains high in the ranking with an estimated incidence at 1% per month of travel. Dengue is another commonly encountered infection among international travellers with estimated monthly incidence of 0.5-0.8% among non-immune exposed travellers; the hospitalized proportion was 10 and 22%, respectively, according to two recent publications. With recent yellow fever outbreaks particularly in Brazil, its estimated monthly incidence has risen to >0.1%. Meanwhile, improvements in hygiene and sanitation have led to some decrease in foodborne illnesses; however, hepatitis A monthly incidence remains substantial in most developing regions (0.001-0.01%) and typhoid remains particularly high in South Asia (>0.01%). Mpox, a newly emerged disease that demonstrated worldwide spread through mass gathering and travel, cannot be quantified regarding its travel-related risk.

CONCLUSION

The data summarized may provide a tool for travel health professionals to prioritize preventive strategies for their clients against VPD. Updated assessments on incidence and impact are ever more important since new vaccines with travel indications (e.g. dengue) have been licensed or are undergoing regulatory review.

Travel-associated melioidosis: a narrative review

BACKGROUND

Melioidosis, caused by Burkholderia pseudomallei, may be considered a neglected tropical disease that remains underdiagnosed in many geographical areas. Travellers can act as the sentinels of disease activity, and data from imported cases may help complete the global map of melioidosis.

METHODS

A literature search for imported melioidosis for the period 2016-22 was performed in PubMed and Google Scholar.

RESULTS

In total, 137 reports of melioidosis associated with travel were identified. The majority were males (71%) and associated with exposure in Asia (77%) (mainly Thailand, 41%, and India, 9%). A minority acquired the infection in the Americas-Caribbean area (6%), Africa (5%) and Oceania (2%). The most frequent comorbidity was diabetes mellitus (25%) followed by underlying pulmonary, liver or renal disease (8, 5 and 3%, respectively). Alcohol/tobacco use were noted for seven and six patients, respectively (5%). Five patients (4%) had associated non-human immunodeficiency virus (HIV)-related immunosuppression, and three patients (2%) had HIV infection. One patient (0.8%) had concomitant coronavirus disease 19. A proportion (27%) had no underlying diseases. The most frequent clinical presentations included pneumonia (35%), sepsis (30%) and skin/soft tissue infections (14%). Most developed symptoms <1 week after return (55%), and 29% developed symptoms >12 weeks after. Ceftazidime and meropenem were the main treatments used during the intensive intravenous phase (52 and 41% of patients, respectively) and the majority (82%) received co-trimoxazole alone/combination, for the eradication phase. Most patients had a favourable outcome/survived (87%). The search also retrieved cases in imported animals or cases secondary to imported commercial products.

CONCLUSIONS

As post-pandemic travel soars, health professionals should be aware of the possibility of imported melioidosis with its diverse presentations. Currently, no licensed vaccine is available, so prevention in travellers should focus on protective measures (avoiding contact with soil/stagnant water in endemic areas). Biological samples from suspected cases require processing in biosafety level 3 facilities.

Dengue vaccine development: challenges and prospects

PURPOSE OF REVIEW

Dengue vaccine development is a high public health priority. To date, no dengue vaccine is in widespread use. Here we review the challenges in dengue development and the latest results for the second-generation dengue vaccines.

RECENT FINDINGS

The biggest hurdle is the immunological interaction between the four antigenically distinct dengue serotypes. The advantages of second-generation dengue vaccines are the inclusion of nonstructural proteins of the dengue backbone and a more convenient dosing with reduced numbers of doses needed.

SUMMARY

Although dengue-primed individuals can already benefit from vaccination with the first licensed dengue vaccine CYD-TDV, the public health need for the dengue-naive population has not yet been met. The urgent need remains to identify correlates of both protection and enhancement; until such correlates have been identified, all second-generation dengue vaccines still need to go through full phase 3 trials. The 5-year efficacy and safety data for both second-generation dengue vaccines are imminent.

[Knowledge of malaria and preventive attitudes of Tunisian travellers toward malaria endemic areas]

Introduction

travellers to endemic areas must know malaria, its risk factors and prophylactic measures. This can help to avoid severe cases of malaria and to prevent transmission in countries that are malaria-free. The purpose of this study is to assess Tunisian travellers´ knowledge about malaria, its transmission and prevention and their adherence to prophylactic measures.

Methods

we conducted a survey based on two anonymous questionnaires (pre- and post-trip) among adults travelling to endemic countries. The 1st questionnaire was followed by a medical interview focusing on level of risk and recommended prophylactic measures.

Results

two hundred and eighty-nine travellers were recruited. They mainly moved within sub-Saharan Africa (99%) for professional reasons (84,4%). The average age of subjects was 42.3 years and sex ratio (male/female) was 3.1. Prior to departure, only 53.3% of subjects were aware of the risk of malaria, and only 28% gave correct answers about modes of transmission. Recommendations for chemoprophylaxis were only known by 62.3% of subjects and only 43.6% intended to use chemoprophylaxis (p < 0.01). Better adherence to protective measures, including chemoprophylaxis, was reported after the trip, with attitudes qualified as good or excellent by 64.2% on return against 23.7% before the interview (<0.001).

Conclusion

Tunisian travellers knowledge of malaria is insufficient. Strengthening information through specialized consultations (whose usefulness has been demonstrated) is required.

Bacterial travellers' diarrhoea: A narrative review of literature published over the past 10 years

Travellers' diarrhoea (TD) is the most frequent illness experienced by international travellers to lower-income countries with bacterial agents considered to account for 80-90% of cases. In this review, we summarise evidence published on bacterial TD over the past 10 years, focusing on the epidemiology and aetiology of TD. Diarrhoeagenic Escherichia coli (DEC) continue to be the most commonly implicated bacteria in TD, although Enteropathogenic E. coli (EPEC) and Enteroaggregative E. coli (EAEC) now appear to be predominant where Enterotoxigenic E. coli (ETEC) was previously considered most prevalent globally. Where fluroquinolone resistance had primarily been documented for Campylobacter in Southeast Asia, widespread resistance has been observed in most regions of the world for multiple enteropathogens, including Shigella, Salmonella, ETEC and EAEC. Implementation of novel molecular methods for pathogen detection has led to identification of bacterial pathogens, including Clostridium difficile (with and without the use of prior antibiotics), Arcobacter species and Bacteroides fragilis, as aetiological agents in TD. The widespread resistance to first-line antibiotics in multiple bacterial enteropathogens warrants continued surveillance and re-evaluation of current treatment practices. Further investigations are required to determine the prevalence and geographical distribution of bacterial enteropathogens that have been more recently implicated in TD.

Key informant perspectives on sexual health services for travelling young adults: a qualitative study

BACKGROUND

International travel has become increasingly popular among young adults. Young adults often engage in casual sexual relationships abroad, exhibit sexual risk behaviours and may thus be at risk of contracting sexually transmitted and blood-borne infections. Pre-travel interventions and consultations may mitigate this risk. At present, we know little about sexual health-related pre-travel interventions. The aim of this study was therefore to document key informants' experiences, perceptions and recommendations in the context of sexual health of young adult travellers.

METHODS

Key informants were professionals working in Ottawa, Canada travel clinics, travel organizations or sexual health clinics with a young adult clientele. This study used a qualitative approach and consisted of 13 in-person or Skype semi-structured interviews with key informants. Thematic content analysis was informed by a sexual health framework, with themes emerging both inductively and deductively.

RESULTS

Sexual health was not common in pre-travel interventions described by key informants. Risk-assessment, and practical or purpose-driven pre-travel interventions were identified, resulting in risk mitigation strategies tailored to the destination region and/or mission/culture of the travel organization. Dissemination (e.g. limited time, lack of training) and uptake (e.g. young adults' embarrassment, provider discomfort, financial constraints) barriers limited in-depth discussions of pre-travel interventions related to sexual health. Key informants acknowledged the importance of early sexual health education, and recommended ongoing, comprehensive sexual education for both youth and young adults.

CONCLUSION

The findings of this study suggest that more time and resources should be allocated to the topic of sexual health during pre-travel interventions with young adults. Professionals who guide and prepare young adults for travel must develop concomitant skills in sexual health promotion. Early, comprehensive sexual education is recommended to improve overall sexual health in young adults and mitigate risk behaviours during travel.

Flexible global working arrangements: An integrative review and future research agenda

The topography of global mobility within multinational enterprises (MNEs) is evolving where we now have a portfolio of flexible global working arrangements (FGWAs) including: international business travellers, flexpatriates, short-term international assignees, international commuters, and rotational assignees. The need for more agile structures and more efficient mechanisms to transfer globally dispersed knowledge are two key enablers in this evolution. With increased interest, this paper offers the first systematic, integrative review of 100 articles on FGWAs. The review indicates that these forms of global work appear to be a somewhat overlooked double-edged sword in that they may confer significant but unrealised value for MNEs alongside hidden, adverse consequences for individuals. Notable was the lack of insight into the HR function's input or oversight at either a strategic or operational level. We find that there is a distinct lack of strategic linkages to global mobility and/or HR functions. We propose a research agenda that centres on better understanding the international HR function's role and responsibility in providing a more strategic and sustainable perspective of these increasingly common FGWAs alongside virtual work. The COVID-19 pandemic may offer a critical juncture point in which there is greater strategic consideration on the utilisation and support of such arrangements.

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This is the first systematic review on flexible global working arrangements

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There is a clear imbalance in representation of the work arrangements in the literature

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Value creation and destruction highlight the doubled-edged nature of such work

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There is a lack of research into the HR function's input or oversight

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Research on strategic IHRM integration and sustainable management is proposed

If I told you that there is no need for yellow fever vaccine booster would you still come to the travel clinic?: a cross-sectional study

Background

Yellow Fever (YF) immunization required a single dose vaccine with boosters every 10 years. After International Health Regulation (IHR) amendment annex 7 (July 2016), it was accepted that a single dose confers lifelong immunity. Since pre-travel advice is as important as vaccination when traveling, it is essential to clarify why travelers come to a travel health consultation, with the possibility of IHR amendment having a negative impact on travelers’ health. This study aims to describe travelers’ reasons to come to a pre-travel consultation in Lisbon and if they would return if they wouldn’t need the YF vaccine booster.

Methods

An observational cross-sectional study was conducted during 5 months in the waiting room of Instituto de Higiene e Medicina Tropical travel clinic in Lisbon, Portugal. Travelers were asked about sociodemographic characteristics, destination country, travel duration and reasons to travel in an anonymous self-administered questionnaire.

Results

A total of 1043 travelers agreed to participate in the study. Although 61.0% (627/1028) did not come to the clinic to get the YF vaccine, from those who did, 36.7% (133/362) would not come and 12.9% (47/362) didn’t knew if they would come if the vaccine would not be necessary.

Conclusion

The IHR amendment may have a negative impact on travel clinic attendance and on travelers´ health.

Association Between Business Travel, Health-Related Behaviors, and Adiposity

OBJECTIVE

To evaluate the associations between frequency of business travel and health behaviors and adiposity.

METHODS

Retrospective cross-sectional analysis of de-identified electronic medical records from 795 corporate physical exams.

RESULTS

Business travel frequency demonstrates a curvilinear relationship with body mass index and body composition in men and women, with domestic and international travel. Linear and quadratic term beta coefficients indicate stronger associations between the sum of domestic and international travel and BMI, body fat percentage, and visceral adipose tissue in women than men, after accounting for age, exercise, and sleep. Based on our male sample population, international travel frequency has a greater influence on adiposity than summed (mostly domestic) travel.

CONCLUSIONS

Frequent business travel adversely affects body composition, with differences by gender and type of travel.

Implementation strategies for the first licensed dengue vaccine: A meeting report

Dengue vaccination would enhance the control of dengue, one of the most frequent vector-borne viral diseases globally. CYD-TDV is the first dengue vaccine to be licensed, but global uptake has been hampered due to its use being limited to seropositive persons aged 9 years and above, and the need for a 3-dose schedule. The Partnership for Dengue Control (PDC) organized a meeting with key opinion leaders and stakeholders to deliberate on implementation strategies for the use of CYD-TDV. New data have emerged that support the shortening of the primary schedule from a 3 to 2 dose schedule, extending the age range below 9 to 6 years of age, and expanding the indication from endemic populations to also include travelers to endemic areas. Cost-effectiveness may improve with the modified 2-dose regimen and with multiple testing. Strategies to implement a dengue vaccination program have been developed, in particular school-based strategies. A range of delivery scenarios can then be considered, using various settings for each step of the intervention. However, several challenges remain, including communication about limiting the use of this vaccine to seropositive individuals only. Affordability will vary from country to country, as will government commitment and community acceptance. Well-tailored communication strategies that target key stakeholders are expected to make up a significant part of any future dengue vaccination program.

Injury and illness epidemiology in professional Asian football: lower general incidence and burden but higher ACL and hamstring injury burden compared with Europe

BACKGROUND

While football injury and illness epidemiology surveillance at professional club level in Europe is available, epidemiological data from other continents are lacking.

PURPOSE

Investigating injury and illness epidemiology in professional Asian football.

STUDY DESIGN

Descriptive prospective study.

METHODS

Professional teams from the Asian Football Confederation (AFC) league were followed prospectively for three consecutive AFC seasons (2017 through 2019, 13 teams per season, 322 team months). Time-loss injuries and illnesses in addition to individual match and training exposure were recorded using standardised digital tools in accordance with international consensus procedures.

RESULTS

In total, 232 665 hours of exposure (88.6% training and 11.4% matches) and 1159 injuries were recorded; 496 (42.8%) occurred during matches, 610 (52.6%) during training; 32 (2.8%) were reported as 'not applicable' and for 21 injuries (1.8%) information was missing. Injury incidence was significantly greater during match play (19.2±8.6 injuries per 1000 hours) than training (2.8±1.4, p<0.0001), resulting in a low overall incidence of 5.1±2.2.The injury burden for match injuries was greater than from training injuries (456±336 days per 1000 hours vs 54±34 days, p<0.0001). The two specific injuries causing the greatest burden were complete ACL ruptures (0.14 injuries (95% CI 0.9 to 0.19) and 29.8 days lost (29.1 to 30.5) per 1000 hours) and hamstring strains (0.86 injuries (0.74 to 0.99) and 17.5 days (17.0 to 18.1) lost per 1000 hours).Reinjuries constituted 9.9% of all injuries. Index injuries caused 22.6±40.8 days of absence compared with 25.1±39 for reinjuries (p=0.62). The 175 illnesses recorded resulted in 1.4±2.9 days of time loss per team per month.

CONCLUSION

Professional Asian football is characterised by an overall injury incidence similar to that reported from Europe, but with a high rate of ACL ruptures and hamstring injury, warranting further investigations.

What Is the Impact of Lockdowns on Dengue?

PURPOSE OF REVIEW

Societal lockdowns in response to the COVID-19 pandemic have led to unprecedented disruption to daily life across the globe. A collateral effect of these lockdowns may be a change to transmission dynamics of a wide range of infectious diseases that are all highly dependent on rates of contact between humans. With timing, duration and intensity of lockdowns varying country-to-country, the wave of lockdowns in 2020 present a unique opportunity to observe how changes in human contact rates, disease control and surveillance affect dengue virus transmission in a global natural experiment. We explore the theoretical basis for the impact of lockdowns on dengue transmission and surveillance then summarise the current evidence base from country reports.

RECENT FINDINGS

We find considerable variation in the intensity of dengue epidemics reported so far in 2020 with some countries experiencing historic low levels of transmission while others are seeing record outbreaks. Despite many studies warning of the risks of lockdown for dengue transmission, few empirically quantify the impact and issues such as the specific timing of the lockdowns and multi-annual cycles of dengue are not accounted for. In the few studies where such issues have been accounted for, the impact of lockdowns on dengue appears to be limited.

SUMMARY

Studying the impact of lockdowns on dengue transmission is important both in how we deal with the immediate COVID-19 and dengue crisis, but also over the coming years in the post-pandemic recovery period. It is clear lockdowns have had very different impacts in different settings. Further analyses might ultimately allow this unique natural experiment to provide insights into how to better control dengue that will ultimately lead to better long-term control.

End of year editorial: hot topics in travel medicine

COVID-19 will reshape travel medicine, in particular in relation to business travellers and the use of digital technologies. Although the hot topic in travel medicine was the COVID-19 pandemic, travel-associated measles, yellow fever and rabies deserve some special attention.

GeoSentinel: past, present and future†

RATIONALE FOR REVIEW

In response to increased concerns about emerging infectious diseases, GeoSentinel, the Global Surveillance Network of the International Society of Travel Medicine in partnership with the US Centers for Disease Control and Prevention (CDC), was established in 1995 in order to serve as a global provider-based emerging infections sentinel network, conduct surveillance for travel-related infections and communicate and assist global public health responses. This review summarizes the history, past achievements and future directions of the GeoSentinel Network.

KEY FINDINGS

Funded by the US CDC in 1996, GeoSentinel has grown from a group of eight US-based travel and tropical medicine centers to a global network, which currently consists of 68 sites in 28 countries. GeoSentinel has provided important contributions that have enhanced the ability to use destination-specific differences to guide diagnosis and treatment of returning travelers, migrants and refugees. During the last two decades, GeoSentinel has identified a number of sentinel infectious disease events including previously unrecognized outbreaks and occurrence of diseases in locations thought not to harbor certain infectious agents. GeoSentinel has also provided useful insight into illnesses affecting different traveling populations such as migrants, business travelers and students, while characterizing in greater detail the epidemiology of infectious diseases such as typhoid fever, leishmaniasis and Zika virus disease.

CONCLUSIONS

Surveillance of travel- and migration-related infectious diseases has been the main focus of GeoSentinel for the last 25 years. However, GeoSentinel is now evolving into a network that will conduct both research and surveillance. The large number of participating sites and excellent geographic coverage for identification of both common and illnesses in individuals who have traversed international borders uniquely position GeoSentinel to make important contributions of travel-related infectious diseases in the years to come.

Dengue, chikungunya and Zika in GeoSentinel surveillance of international travellers: a literature review from 1995 to 2020

INTRODUCTION

GeoSentinel is a global surveillance network of travel medicine providers seeing ill-returned travellers. Much of our knowledge on health problems and infectious encountered by international travellers has evolved as a result of GeoSentinel surveillance, providing geographic and temporal trends in morbidity among travellers while contributing to improved pre-travel advice. We set out to synthesize epidemiological information, clinical manifestations and time trends for dengue, chikungunya and Zika in travellers as captured by GeoSentinel.

METHODS

We conducted a systematic literature search in PubMed on international travellers who presented with dengue, chikungunya or Zika virus infections to GeoSentinel sites around the world from 1995 until 2020.

RESULTS

Of 107 GeoSentinel publications, 42 articles were related to dengue, chikungunya and/or Zika. The final analyses and synthesis of and results presented here are based on the findings from 27 original articles covering the three arboviral diseases.

CONCLUSIONS

Dengue is the most frequent arboviral disease encountered in travellers presenting to GeoSentinel sites, with increasing trends over the past two decades. In Southeast Asia, annual proportionate morbidity increased from 50 dengue cases per 1000 ill returned travellers in non-epidemic years to an average of 159 cases per 1000 travellers during epidemic years. The highest number of travellers with chikungunya virus infections was reported during the chikungunya outbreak in the Americas and the Caribbean in the years 2013-16. Zika was first reported by GeoSentinel already in 2012, but notifications peaked in the years 2016-17 reflecting the public health emergency in the Americas at the time.

Re-starting travel in the era of COVID-19: preparing anew

Travel, a major contributor to global economy, needs to adapt to the coronavirus disease 2019 (COVID-19) pandemic. Restarting business and travel share convergent considerations. Travel health preparation will require detailed assessment to specifically address COVID-19: the individual’s personal risk stratification, elements of travel and policies imposed on each traveller and itinerary. Precise details of the trip will help to formulate beneficial recommendations.

Dengue vaccine development by the year 2020: challenges and prospects

The first licensed dengue vaccine led to considerable controversy, and to date, no dengue vaccine is in widespread use. All three leading dengue vaccine candidates are live attenuated vaccines, with the main difference between them being the type of backbone and the extent of chimerization. While CYD-TDV (the first licensed dengue vaccine) does not include non-structural proteins of dengue, TAK-003 contains the dengue virus serotype 2 backbone, and the Butantan/Merck vaccine contains three full-genomes of the four dengue virus serotypes. While dengue-primed individuals can already benefit from vaccination against all four serotypes with the first licensed dengue vaccine CYD-TDV, the need for dengue-naive population has not yet been met. To improve tetravalent protection, sequential vaccination should be considered in addition to a heterologous prime-boost approach.

Malaria Disease and Chemoprophylaxis Usage among Israeli Travelers to Endemic Countries

Prevention of malaria in travelers to endemic countries is one of the complex challenges of travel medicine. Israel has a widespread culture of travel to developing countries, but information regarding malaria prevention is limited so far. Our study, conducted in Sheba Medical Center, Israel, during the years 2008-2018 examined malaria chemoprophylaxis usage and malaria cases in a large group of Israeli travelers returning from endemic countries with any medical complaint. Data were collected regarding travel destinations, conditions, duration of stay, and pretravel consultation. Altogether, 4,708 travelers were included in our study. Travel destinations included Asia (51%), Latin America (31%), and sub-Saharan Africa (SSA) (17%). Median travel duration was 26 days. Only 11.9% reported taking malaria chemoprophylaxis. Of the travelers to SSA, 41.3% took prophylaxis as opposed to only 6% outside of Africa. During the study years, 136 cases of malaria were diagnosed; among them, 82 (60%) were infected with Plasmodium falciparum, of whom all but two were from SSA and none adhered to prophylaxis. Malaria chemoprophylaxis usage was found to be negligible in travel to many countries still considered endemic. Higher prophylaxis usage was found among travelers to SSA, but numbers are still lower than recommended. The low number of malaria cases seen in destinations outside SSA, as documented in our cohort, is likely to represent travel to low risk areas and not high prophylaxis usage. We urge re-evaluation of current CDC and Israeli guidelines which still recommend using chemoprophylaxis in many low-risk countries, as focus on high-risk countries may increase adherence.

ZikaPLAN: addressing the knowledge gaps and working towards a research preparedness network in the Americas

Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN`s mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network.

A Prospective Study on the Impact and Out-of-Pocket Costs of Dengue Illness in International Travelers

Although the costs of dengue illness to patients and households have been extensively studied in endemic populations, international travelers have not been the focus of costing studies. As globalization and human travel activities intensify, travelers are increasingly at risk for emerging and reemerging infectious diseases, such as dengue. This exploratory study aims to investigate the impact and out-of-pocket costs of dengue illness among travelers. We conducted a prospective study in adult travelers with laboratory-confirmed dengue and recruited patients at travel medicine clinics in eight different countries from December 2013 to December 2015. Using a structured questionnaire, we collected information on patients and their health-care utilization and out-of-pocket expenditures, as well as income and other financial losses they incurred because of dengue illness. A total of 90 patients participated in the study, most of whom traveled for tourism (74%) and visited countries in Asia (82%). Although 22% reported hospitalization and 32% receiving ambulatory care while traveling, these percentages were higher at 39% and 71%, respectively, after returning home. The out-of-pocket direct and indirect costs of dengue illness were US$421 (SD 744) and US$571 (SD 1,913) per episode, respectively, averaging to a total out-of-pocket cost of US$992 (SD 2,052) per episode. The study findings suggest that international travelers incur important direct and indirect costs because of dengue-related illness. This study is the first to date to investigate the impact and out-of-pocket costs of travel-related dengue illness from the patient's perspective and paves the way for future economic burden studies in this population.

Dengue vaccine development: status and future

Dengue, the most common arbovirus, represents an increasingly significant cause of morbidity worldwide, including in travelers. After decades of research, the first dengue vaccine was licensed in 2015: CYD-TDV, a tetravalent live attenuated vaccine with a yellow fever vaccine backbone. Recent analyses have shown that vaccine performance is dependent on serostatus. In those who have had a previous dengue infection, i.e., who are seropositive, the efficacy is high and the vaccine is safe. However, in seronegative vaccinees, approximately 3 years after vaccination the vaccine increases the risk of developing severe dengue when the individual experiences a natural dengue infection.

The World Health Organization recommends that this vaccine be administered only to seropositive individuals. Current efforts are underway to develop rapid diagnostic tests to facilitate prevaccination screening. Two second-generation dengue vaccine candidates, both also live attenuated recombinant vaccines in late-stage development, may not present the same limitations because of differences in the backbone used, but results of phase 3 trials need to be available before firm conclusions can be drawn.

Dengue is increasingly frequent in travelers, but the only licensed dengue vaccine to date can be used only in seropositive individuals. However, the vast majority of travelers are seronegative. Furthermore, the primary series of three doses given 6 months apart renders this vaccine difficult in the travel medicine context.

Antimicrobial Resistance in the Asia Pacific region: a meeting report

The Asia Pacific region, home to two-thirds of the world's population and ten of the least developed countries, is considered a regional hot-spot for the emergence and spread of antimicrobial resistance (AMR). Despite this, there is a dearth of high-quality regional data on the extent of AMR. Recognising the urgency to close this gap, Singapore organised a meeting to discuss the problems in the region and frame a call for action. Representatives from across the region and beyond attended the meeting on the "Antimicrobial Resistance in the Asia Pacific & its impact on Singapore" held in November 2018. This meeting report is a summary of the discussions on the challenges and progress in surveillance, drivers and levers of AMR emergence, and the promising innovations and technologies that could be used to combat the increasing threat of AMR in the region. Enhanced surveillance and research to provide improved evidence-based strategies and policies are needed. The major themes that emerged for an action plan are working towards a tailored solution for the region by harnessing the One Health approach, enhancing inter-country collaborations, and collaboratively leverage upon new emerging technologies. A regionally coordinated effort that is target-driven, sustainable and builds on a framework facilitating communication and governance will strengthen the fight against AMR in the Asia Pacific region.

Characteristics and Severity of Disease among 100 Cases of Imported Malaria Seen at a U.S. University Hospital, 2000-2017

Malaria acquired in endemic areas poses a substantial risk to travelers arriving in or returning to the United States. Timely diagnosis and recognition of severe illness are crucial; however, many U.S.-based clinicians lack familiarity with this disease. We conducted a retrospective review of 100 cases of malaria in adults seen at a single urban university hospital during 2000-2017. Descriptive and analytical statistics were calculated, including logistic regression modeling case severity. Most of the patients presented with Plasmodium falciparum (76%), most commonly after travel from sub-Saharan Africa (94%). Prior malaria experience was common (50%), but adherence to a prophylactic regimen was exceedingly rare (4%). Twenty-one patients had severe malaria, including 10 with cerebral malaria. Severity was predicted by high parasitemia, bandemia, hypoglycemia, and hypotension at the time of presentation. In 24 patients, the initial treatment regimen was changed, usually because of the appearance of clinical deterioration or drug toxicity. One patient required intravenous artesunate. All patients survived, although one suffered fetal loss. Among 30 patients initially evaluated at other institutions, 43% had been treated for an alternative diagnosis. The most common reasons for transfer of patients to our hospital were inadequate facilities and lack of expertise with malaria. There needs to be increased awareness among U.S.-based travelers and clinicians regarding malaria as a potentially lethal condition, emphasizing the use of appropriate prophylaxis. Our simple model of disease severity could serve frontline physicians when deciding which patients should be admitted to the intensive care unit or transferred for higher level care.

Determinants of Compliance of Travelers with Vaccination and Malaria Prophylaxis at a Travel Clinic

BACKGROUND

Pre-travel medical consultation is essential to reduce health impairment during travel. Yellow fever vaccination (YFV) is mandatory to enter some endemic countries. In this study, we evaluated the factors that affect compliance with appropriate prevention of infectious diseases in travelers who visited clinic for YFV.

METHODS

For this retrospective study, chart reviews for 658 patients who visited a travel clinic for YFV before travel were conducted. The period of this study was from January 2016 to September 2018. The associations between appropriate vaccination and factors such as travel duration, destination, time of visiting clinic before departure, and purpose of travel were analyzed.

RESULTS

Among 658 patients who got YFV during the study period, 344 patients (52.3%) received additional vaccination or malaria prophylaxis following a physician's recommendation. Travelers who visited the clinic more than 21 days before departure were more compliant than those who visited 14 days or fewer before departure (odds ratio [OR], 1.90; 95% confidence interval [CI], 1.23-2.93; P = 0.004). Travelers visiting Africa were more compliant than were those traveling to South and Central America (OR, 1.97; 95% CI, 1.34-2.90; P = 0.001). Travelers in age groups of 40-49 years and over 70 years were less compliant than the 18-29 years old population (OR, 0.51; 95% CI, 0.28-0.93; P = 0.027 and OR, 0.19; 95% CI, 0.04-0.84; P = 0.03, respectively). Also, those who traveled for tour or to visit friends or relatives were more compliant than those who departed for business (OR, 0.77; 95% CI, 1.03-3.56; P = 0.04).

CONCLUSION

For appropriate vaccination, pre-travel consultation at least 3 weeks before departure is crucial. Travelers should be aware of required vaccination and malaria prophylaxis before visiting South and Central America and Asia. Plans to enhance compliance of the elderly and business travelers should be contrived.

Insights into needs of business travelers to China from calls to a medical assistance provider

Background

Although 17.5% of German travelers were business travelers in the years 2011–2013, little is known about their pathologies. Recent publications indicate that infections are the primary health issue in general travelers. Our aim was to investigate whether business travelers from Germany to China also primarily suffer from infections.

Methods

From 2011 to 2013, 587 calls for service of German business travelers to China were collected by a medical assistance provider. 482 of these calls were evaluated regarding demographics, reported diseases and conditions and the type of service provided by the medical assistance company.

Results

The most common reasons for calls for service were “factors influencing health status and contact with health service” (18.8%), “injury and poisoning” (16.0%) as well as “symptoms, signs, and ill-defined conditions” (13.7%). Most patients asked for “medical advice” (37.8%), referral to “outpatient care” (25.1%) or “inpatient care” (16.6%). “Evacuation and/or repatriation” was required mainly due to “injury and poisoning” (n = 12), “diseases of the circulatory system” (n = 5) or “mental disorders” (n = 3).

Conclusion

German business travelers to China are seeking primarily administrative support from a medical assistance provider and are mostly affected by non-infectious diseases. Pre-travel preparation of such travelers need to place more emphasis on non-communicable health risks and prevention.

Changing trends and pretravel preparation of business travelers from Greece during the financial crisis

OBJECTIVES

Unemployment in Greece has been increasing as a result of the financial crisis. The aim of this study was to assess the changing trends of business travelers and their pretravel preparation.

STUDY DESIGN

Prospective, questionnaire-based study.

METHODS

The study was conducted between 2008 and 2016 at all Regional Public Health Departments. All travelers seeking pretravel advice during the study period were invited to participate.

RESULTS

A total of 12,379 travelers completed the questionnaire, 58% of whom were business travelers. Between 2008 and 2016, the proportion of business travelers increased from 33% to 80.7% and those travelling for recreational purposes decreased from 47.9% to 15.5%. Business travelers sought pretravel advice at a mean of 18.5 days before departure; 89.1% were men with a mean age of 34.4 years. The Middle East was the most common destination (47.8%) followed by Sub-Saharan Africa (28.3%). Most business travelers stayed in urban areas (77.6%) and for ≥ 1 month (68.6%). Yellow fever vaccine was administered to 75% of business travelers. A total of 76.2%, 26.9%, 15.5%, and 13.9% of those visiting Sub-Saharan Africa received yellow fever, typhoid fever, hepatitis A, and meningococcal vaccines, respectively. Malaria prophylaxis vaccine was administered to 26.8% of business travelers; including 46.5% of those traveling to Sub-Saharan Africa and 53.5% to those traveling to the Indian subcontinent.

CONCLUSIONS

There is an increasing trend for business travel from Greece, especially to developing countries. Improving the knowledge of travel health consultants about the risks of business travel and the pretravel preparation of business travelers is crucial.

Reducing infectious disease inequities among migrants

BACKGROUND

migration has reached unprecedented levels, with 3.6% of the world's population living outside their country of birth. Migrants comprise a substantial proportion of high-income country populations, are at increased risk of a range of infectious diseases, compared to native-born populations and may experience worse health outcomes due to barriers accessing timely diagnoses and treatment. Poor access to essential healthcare services can be attributed to several factors, including language and cultural barriers and lack of specific inclusive health policies.

METHODS

This review draws on evidence from the immigrant health and travel medicine literature, with a focus on infectious disease risks. It presents strategies to reduce barriers to healthcare access through health promotion and screening programs both at the community and clinic level and the delivery of linguistically and culturally competent care. The Methods: Salud Entre Culturas (SEC) 'Health Between Cultures' project from the Tropical Medicine Unit at the Hospital Ramon y Cajal in Madrid is described as an effective model of care.

RESULTS

For those providing healthcare to migrant populations, the use of community-consulted approaches are considered best practice in the development of health education, health promotion and the delivery of targeted health services. At the clinic-level, strategies optimizing care for migrants include the use of bilingual healthcare professionals or community-based healthcare workers, cultural competence training of all clinic staff, the appropriate use of trained interpreters and the use of culturally appropriate health promotion materials.

CONCLUSIONS

Multifaceted strategies are needed to improve access, community knowledge, community engagement and healthcare provider training to provide appropriate care to migrant populations to reduce infectious disease disparities.

Spectrum of illness in migrants to Canada: sentinel surveillance through CanTravNet

BACKGROUND

Due to ongoing political instability and conflict in many parts of the world, migrants are increasingly seeking asylum and refuge in Canada.

METHODS

We examined demographic and travel correlates of illnesses among migrants to Canada to establish a detailed epidemiologic framework of this population for Canadian practitioners. Data on ill-returned Canadian travellers presenting to a CanTravNet site between 1 January 2015 and 31 December 2015 were analyzed.

RESULTS

During the study period, 2415 ill travellers and migrants presented to a CanTravNet site, and of those, 519 (21.5%) travelled for the purpose of migration. Sub-Saharan Africa (n = 160, 30.8%), southeast Asia (n = 84, 16.2%) and south central Asia (n = 75, 14.5%) were the most common source regions for migrants, while the top specific source countries, of 98 represented, were the Philippines (n = 45, 8.7%), China (n = 36, 6.9%) and Vietnam (n = 31, 6.0%). Compared with non-migrant travellers, migrants were more likely to have a pre-existing immunocompromising medical condition, such as HIV or diabetes mellitus (P < 0.0001), and to require inpatient management of their illness (P < 0.0001). Diagnoses such as tuberculosis (n = 263, 50.7%), hepatitis B and C (n = 78, 15%) and HIV (n = 11, 2.1%) were over-represented in the migrant population compared with non-migrant travellers (P < 0.0001). Most cases of tuberculosis in the migrant population (n = 263) were latent (82% [n = 216]); only 18% (n = 47) were active.

CONCLUSIONS

Compared with non-migrant travellers, migrants were more likely to present with a communicable infectious disease, such as tuberculosis, potentially complicated by an underlying immunosuppressing condition such as HIV. These differences highlight the divergent healthcare needs in the migrant population, and underscore the importance of surveillance programmes to understand their burden of illness. Intake programming should be adequately resourced to accommodate the medical needs of this vulnerable population of new Canadians.

Spatiotemporal characterisation and risk factor analysis of malaria outbreak in Cabo Verde in 2017

Background

Cabo Verde is a country that has been in the pre-elimination stage of malaria since the year 2000. The country is still reporting cases, particularly in the capital of Praia, where more than 50% of the national population live. This study aims to examine the spatial and temporal epidemiological profile of malaria across the country during the 2017 outbreak and to analyse the risk factors, which may have influenced the trend in malaria cases.

Methods

Longitudinal data collected from all malaria cases in Cabo Verde for the year 2017 were used in this study. The epidemiological characteristics of the cases were analysed. Local and spatial clusters of malaria from Praia were detected by applying the Cluster and Outlier Analysis (Anselin Local Moran's I) to determine the spatial clustering pattern. We then used the Pearson correlation coefficient to analyse the relationship between malaria cases and meteorological variables to identify underlying drivers.

Results

In 2017, 446 cases of malaria were reported in Cabo Verde with the peak of cases in October. These cases were primarily Plasmodium falciparum infections. Of these cases, 423 were indigenous infections recorded in Praia, while 23 were imported malaria cases from different African countries. One case of P. vivax infection was imported from Brazil. Spatial autocorrelation analysis revealed a cluster of high-high malaria cases in the centre of the city. Malaria case occurrence has a very weak correlation (r = 0.16) with breeding site location. Most of the cases (69.9%, R ² = 0.699) were explained by the local environmental condition, with temperature being the primary risk factor followed by relative humidity. A moderately positive relationship was noted with the total pluviometry, while wind speed had a strong negative influence on malaria infections.

Conclusions

In Cabo Verde, malaria remains a serious public health issue, especially in Praia. The high number of cases recorded in 2017 demonstrates the fragility of the situation and the challenges to eliminating indigenous malaria cases and preventing imported cases. Mosquito breeding sites have been the main risk factor, while temperature and precipitation were positively associated with malaria infection. In light of this study, there is an urgent need to reinforce control strategies to achieve the elimination goal in the country.

Are probiotics and prebiotics effective in the prevention of travellers' diarrhea: A systematic review and meta-analysis

BACKGROUND

Travellers' diarrhea (TD) impacts annually over 20 million tourists, business travellers and military troops on a worldwide basis. Reliance on antibiotic prophylaxis and educational programs has not lead to a significant reduction in TD rates. Previous reviews of probiotics for TD have not accounted for the strain-specificity of probiotic efficacy nor have investigated prebiotics for the prevention of TD.

METHODS

Standard literature databases were searched from 1977 to June 2018 unrestricted by language. Inclusion criteria included: Probiotic, probiotic or symbiotic interventions, randomized, controlled clinical trials (RCTs) and ≥2 RCTs with the same probiotic strain or mixture.

RESULTS

Of 158 screened articles, 12 RCT were included in the systematic review and 6 RCTs (with nine treatment different arms) were included in the meta-analysis. Saccharomyces boulardii CNCM I-745 showed a significant reduction in TD incidence (RR = 0.79, 95% C.I. 0.72-0.87, p < 0.001), while L. rhamnosus GG showed a trend (p = 0.08) and L. acidophilus showed no significant (p = 0.16) reduction of TD.

CONCLUSIONS

The number of trials using probiotics or prebiotics for the prevention of TD continues to be limited in number. Only one of three probiotics showed significant efficacy for the prevention of TD. More research is needed for other probiotics strains and prebiotics to determine if they could also prevent TD.