The elderly, the young and the pregnant traveler -- A retrospective data analysis from a large Swiss Travel Center with a special focus on malaria prophylaxis and yellow fever vaccination

A reporter virus particle seroneutralization assay for tick-borne encephalitis virus overcomes ELISA limitations

Tick-borne encephalitis (TBE) virus is the most prevalent tick-transmitted orthoflavivirus in Europe. Due to the nonspecific nature of its symptoms, TBE is primarily diagnosed by ELISA-based detection of specific antibodies in the patient serum. However, cross-reactivity between orthoflaviviruses complicates the diagnosis. Specificity issues may be mitigated by serum neutralization assays (SNT), although the handling of clinically relevant orthoflaviviruses requires biosafety level (BSL) 3 conditions and they have highly divergent viral kinetics and cell tropisms. In the present study, we established a reporter virus particle (RVP)-based SNT in which the infectivity is measured by luminescence and that can be performed under BSL-2 conditions. The RVP-based SNT for TBEV exhibited a highly significant correlation with the traditional virus-based SNT (R2 = 0.8637, p < 0.0001). The RVP-based assay demonstrated a sensitivity of 92.3% (95% CI: 79.7%-97.4%) and specificity of 100% (95% CI: 81.6%-100%). We also tested the cross-reactivity of serum samples in RVP-based assays against other orthoflaviviruses (yellow fever virus, dengue virus type 2, Zika virus, West Nile virus and Japanese encephalitis virus). Interestingly, all serum samples which had tested TBEV-positive by ELISA but negative by RVP-based SNT were reactive for antibodies against other orthoflaviviruses. Thus, the RVP-based seroneutralization assay provides an added value in clinical diagnostics as well as in epidemiological studies.

Development of a hydrogen peroxide-inactivated vaccine that protects against viscerotropic yellow fever in a non-human primate model

Yellow fever virus (YFV) is endemic in >40 countries and causes viscerotropic disease with up to 20%-60% mortality. Successful live-attenuated yellow fever (YF) vaccines were developed in the mid-1930s, but their use is restricted or formally contraindicated in vulnerable populations including infants, the elderly, and people with compromised immune systems. In these studies, we describe the development of a next-generation hydrogen peroxide-inactivated YF vaccine and determine immune correlates of protection based on log neutralizing index (LNI) and neutralizing titer-50% (NT50) studies. In addition, we compare neutralizing antibody responses and protective efficacy of hydrogen peroxide-inactivated YF vaccine candidates to live-attenuated YFV-17D (YF-VAX) in a rhesus macaque model of viscerotropic YF. Our results indicate that an optimized, inactivated YF vaccine elicits protective antibody responses that prevent viral dissemination and lethal infection in rhesus macaques and may be a suitable alternative for vaccinating vulnerable populations who are not eligible to receive replicating live-attenuated YF vaccines.

Injuries and medical emergencies among international travellers

BACKGROUND

Tropical infectious diseases and vaccine-preventable emergencies are the mainstay of pre-travel consultations. However, non-communicable diseases, injuries and accidents that occur during travel are not emphasized enough in these settings.

METHODS

We performed a narrative review based on a literature search of PubMed, Google Scholar, UpToDate, DynaMed and LiSSa and on reference textbooks and medical journals dedicated to travel, emergency and wilderness medicine. Relevant secondary references were extracted. We also aimed to discuss newer or neglected issues, such as medical tourism, Coronavirus Disease 2019, exacerbations of co-morbidities associated with international travel, insurance coverage, health care seeking abroad, medical evacuation or repatriation and tips for different types of travellers' emergency medical kits (personal, group, physician handled).

RESULTS

All sources reviewed led to the selection of >170 references. Among epidemiological data on morbidity and deaths while abroad, only retrospective data are available. Deaths are estimated to occur in 1 in 100 000 travellers, with 40% caused by trauma and 60% by diseases, and <3% linked to infectious diseases. Trauma and other injuries acquired during travel, such as traffic accidents and drowning, can be reduced by up to 85% with simple preventive recommendations such as avoiding simultaneous alcohol intake. In-flight emergencies occur on 1 in 604 flights on average. Thrombosis risk is two to three times greater for travellers than for non-travellers. Fever during or after travel can occur in 2-4% of travellers, but in up to 25-30% in tertiary centres. Traveller's diarrhoea, although rarely severe, is the most common disease associated with travel. Autochthonous emergencies (acute appendicitis, ectopic pregnancy, dental abscess) can also occur.

CONCLUSIONS

Pre-travel medicine encounters must include the topic of injuries and medical emergencies, such as the risk-taking behaviours and foster better planning in a comprehensive approach along with vaccines and infectious diseases advices.

Characteristics of preventive intervention acceptance for international travel among clients aged 60 years and older from a Japanese multicenter pretravel consultation registry

OBJECTIVES

Pretravel consultation (PTC) is important for older adults owing to health problems associated with overseas travel. Although older adults in Japan, their PTC characteristics are less known. This study aimed to investigate the epidemiology of clients aged ≥ 60 years based on data from the Japan Pre-travel Consultation Registry (J-PRECOR).

METHODS

Clients aged ≥ 60 years who visited J-PRECOR cooperative hospitals from February 1, 2018, to May 31, 2022, were included. The primary endpoint was a comparison of prescriptions for vaccines for hepatitis A, tetanus toxoid, and malaria prophylaxis in travelers to high-risk malaria countries in yellow fever vaccination (YFV)-available facilities with and without YFV.

RESULTS

In total, 1000 clients (median age: 67 years) were included. Although 523 clients were immunized with YFV, only 38.6% of the 961 unimmunized clients were vaccinated with the tetanus toxoid-containing vaccine. Malaria chemoprophylaxis was prescribed to 25.7% of clients traveling for ≤55 days. At YFV-capable institutes, 557 clients traveling to yellow fever risk countries took PTC, 474 of whom received YFV and 83 were unvaccinated. Lower age (odds rate 0.85 per 1 year; 95% CI 0.80-0.90) and lower hepatitis A vaccination rate (0.29; 95% CI 0.14-0.63) were significantly associated with YFV.

CONCLUSIONS

Preventive interventions other than YFV should be offered to older adults.

Arboviral vaccines for use in pregnant travelers

Pregnant women traveling abroad can be exposed to a variety of arboviruses, primarily spread by mosquitoes or ticks. Some arboviral infections can be of particular concern for pregnant women or their fetuses. Vaccination is one preventive measure that can reduce the risk for infection. Several arboviral vaccines have been licensed for many years and can be used to prevent infection in travelers, namely Japanese encephalitis, yellow fever, and tick-borne encephalitis vaccines. Recommendations on use of these vaccines in pregnancy vary. Other arboviral vaccines have been licensed but are not indicated for use in pregnant travelers (e.g., dengue vaccines) or are in development (e.g., chikungunya, Zika vaccines). This review describes arboviral vaccines for travelers, focusing on women who are pregnant and those planning travel during pregnancy.

A Systematic Review and a Meta-Analysis of the Yellow Fever Vaccine in the Elderly Population

We conducted a systematic review and a meta-analysis to assess the risk of serious adverse events in the elderly after yellow fever vaccination compared to the non-elderly population. We searched multiple databases and grey literature, and we selected research without language and publication date restrictions. Studies were analyzed in a descriptive way and meta-analyzed and expressed in terms of prevalence ratio and risk ratio with a 95% confidence interval, depending on the degree of heterogeneity found. A total of 18 studies were included and 11 were meta-analyzed. The results obtained through the meta-analysis showed a risk of serious adverse events after yellow fever vaccination three times higher for the elderly when compared to the non-elderly population and five times higher for persons > 70 years. In relation to adverse event types, viscerotropic disease associated with the yellow fever vaccine had a risk that was six times higher when compared to the population < 60 years. The evidence found supports that the vaccine indication in individuals > 60 years of age should be based on a careful analysis of individual benefit-risk assessments. The results found suggest a higher risk of events for individuals > 70 years, especially for viscerotropic and neurotropic disease associated with YFV contraindicating the use of the YFV in this age group.

Travel patterns and advice-seeking behaviour of pregnant women in the Australian context: A multicentre cross-sectional analysis

BACKGROUND

Travel poses risks to pregnant women, but little data exist describing the travel habits of women during pregnancy or pre-travel recommendations given.

AIMS

To examine travel patterns of pregnant women including frequency of pre-travel consultation, and advice recalled.

MATERIALS AND METHODS

Cross-sectional analysis of post-partum women admitted to five Victorian maternity hospitals between 21 May 2019 and 22 April 2020 in Australia.

RESULTS

Forty-four percent (182/410) of women travelled during pregnancy, 32.9% (135/410) interstate and 19.5% (80/410) internationally. Fifty-five percent travelled for leisure (118/215) and 27% to visit friends/relatives (58/215). Overall, 68.1% (124/182) sought pre-travel advice, primarily from an obstetrician (60.5%, 75/124) or general practitioner (29.8%, 37/124). Only one woman attended a travel clinic. The most common reason for not seeking pre-travel advice was the belief that travel posed no risk (63.4%, 45/71). Pre-travel advice was sought least by those visiting friends/relatives (61.4%, 35/57). Women recalled recommendations regarding travel restrictions by gestational age and venous thromboembolism precautions, but not infectious disease prevention for those to whom it was relevant. Of international travellers, 48.8% (39/80) sought advice from the internet, one-third (13/39) as an alternative to seeing a healthcare provider.

CONCLUSIONS

Travel is common during pregnancy and women seek pre-travel advice from the healthcare provider they see most often during pregnancy. All pregnant women should be provided with consistent, evidence-based pre-travel advice regardless of whom they consult. Further work is needed to educate and provide resources to maternity care providers to optimise pre-travel counselling.

Recent advances in targeting malaria with nanotechnology-based drug carriers

Malaria, as one of the most common human infectious diseases, remains the greatest global health concern, since approximately 3.5 billion people around the world, especially those in subtropical areas, are at the risk of being infected by malaria. Due to the emergence and spread of drug resistance to the current antimalarials, malaria-related mortality and incidence rates have recently increased. To overcome the aforementioned obstacles, nano-vehicles based on biodegradable, natural, and non-toxic polymers have been developed. Accordingly, these systems are considered as a potential drug vehicle, which due to their unique properties such as the excellent safety profile, good biocompatibility, tunable structure, diversity, and the presence of functional groups within the polymer structure, could facilitate covalent attachment of targeting moieties and antimalarials to the polymeric nano-vehicles. In this review, we highlighted some recent developments of liposomes as unique nanoscale drug delivery vehicles and several polymeric nanovehicles, including hydrogels, dendrimers, self-assembled micelles, and polymer-drug conjugates for the effective delivery of antimalarials.

Healthy, safe and responsible: the modern female traveller

One-half of all travellers are women; yet, there is a distinct lack of detailed travel health knowledge on topics of unique relevance to women. While there is medical advice relating to stages in the female lifecycle, it neglects women-specific practical aspects despite their ability to harm travellers’ health and cause inconvenience. This paper discusses comprehensively three major aspects of travel as they relate to women. First, it suggests the management of personal hygiene, bodily functions, menstruation and sexual behaviour, and alerts to the limited knowledge on travel mental health issues.

Second, apart from travelling in a female body with its specific demands, being a woman requires special attention to safety and security. Within various travel contexts, women have many opportunities for minimising potential risks.

Finally, guided by travel medicine’s acknowledgment of its role in the concept of responsible travel, this article goes beyond the usual general statements and broad advice and offers detailed and practical suggestions on how the female traveller can contribute to the overall goal of minimising any potential harm to fellow humans and the natural environment. Recognising the scarcity of women-specific travel information, pathways to better education, and a range of suggestions for urgent research facilitate the provision of high-quality travel health care tailored specifically to women’s needs.

Dietary Supplements Intended for Children--Proposed Classification of Products Available on the Market

Lately, it has been observed that the variety of dietary supplements is rapidly growing. The aim of the study is to extend the classification of dietary supplements (DSs) intended for children above the age of 3, as well as to categorize the ingredients used to manufacture such products. Three hundred fifteen dietary supplements intended for children from 3 to 12 years old, available on the Polish market, were chosen. Evaluation of product specifications provided by the producers, which included lists of ingredients as well as health and nutrition claims found on labels or online, was conducted. Among the available products, one can distinguish supplements with overall health effects used to supplement the diet (such as multivitamin supplements) as well as products for specific conditions, which can be divided into a total of 10 groups of products. Substances that can be found in dietary supplements were also systematized and divided into eight categories, which constitute a division of DSs active ingredients. The results of this research are an extension to the already existing Polish and European classification, which can be applied to classify products intended for children as well as for adults.

Considerations for patients with psoriasis travelling under immunosuppression

With the establishment of modern systemic therapies for psoriasis, comprehensive consultation is required for travelling with immune modulation. Logistic aspects regarding transport and storage, climatic peculiarities of the country of travel and drug dependent risks regarding infections must be considered. Vaccinations and preventive measures are emphasized. Depending on the current national recommendations, special features of vaccinations while under immunosuppression must be taken into account.

Predicting morbidity in older travellers during a short-term stay in the tropics: the ELDEST study

BACKGROUND

Older persons may suffer more from travel-related health problems because of ageing and underlying chronic disorders. Knowledge on who is more likely to have these health problems helps to tailor travel health advice more specifically. This study aimed to determine predictors of travel-related morbidity in older travellers by assessing their pre-travel characteristics and performance using physical and cognitive functioning tests.

METHODS

Multicentre prospective cohort study among older travellers (≥60 years) who consulted one of the participating Dutch travel clinics. Handgrip strength and cognitive performance were measured pre-travel. Participants completed questionnaires before departure and 1 and 4 weeks after return. A diary recorded health complaints during travel until 2-week post-travel.

RESULTS

In total, 477 travellers completed the study (follow-up rate of 97%). Participants' median age was 66 years. The most visited regions were South-East Asia (34%) and South Asia (14%). Median travel duration was 19 days. Polypharmacy (≥5 medications per day) was not uncommon (16%). The median Charlson Comorbidity Index (CCI) score was 0. Self-reported travel-related infectious diseases concerned primarily respiratory tract infections (21%) and gastroenteritis (10%) whereas non-infectious complaints were injuries (13%), peripheral edema (12%) and dehydration (3%). Medical assistance was sought by 18%, mostly post-travel from their general practitioner (87%). Self-reported physical and mental health-related quality of life significantly improved during and after travel. Predictors for an increased risk of travel-related morbidity were higher CCI score, more travel experience, longer travel duration, higher number of daily medications, visiting northern Africa or South-East and East Asia, and phone and social media use.

CONCLUSION

Older Dutch travellers are generally fit, well-prepared and suffer not only from common infectious health problems, but also from injuries. Travel improved their self-perceived health. The predictors could be used to identify the more at-risk older traveller and to decrease travel-related morbidity by optimizing pre-travel advice.

TOURIST2 - Tracking of urgent risks in swiss travellers to the 6 main travel destinations - Feasibility and ethical considerations of a smartphone application-based study

BACKGROUND

The adoption of mHealth technology in travel medicine is a relatively new and unexplored field. We have further developed a TRAVEL application (app) for real-time data monitoring during travel. In this manuscript we report on the feasibility using this new app in a large and diverse cohort of travellers to three continents.

METHODS

We enrolled 1000 participants from the travel clinics of Zurich and Basel, Switzerland, aged ≥18 years, travelling to Thailand, India, China, Tanzania, Brazil and Peru between 09/2017-01/2019. Participants included healthy travellers, individuals with pre-existing chronic diseases and elderly travellers (≥60 years). Participants completed an app-based daily survey on risk behaviours/health incidents pre-, during and after travel. Simultaneously, GPS locations were tightly collected and linked to environmental data.

RESULTS

793 (79%) travellers answered at least one questionnaire during their trip. Participants' median age was 34 years (range 18-84 years); 8% were aged ≥60 years; 55% female; 32% had pre-existing chronic diseases. Completion rates were similar in younger and elderly travellers and in those with and without pre-existing diseases.

CONCLUSIONS

The use of a smartphone app is a feasible method for collecting behavioural and health data in elderly travellers and individuals with chronic diseases travelling to three continents.

Are all vaccines safe for the pregnant traveller? A systematic review and meta-analysis

Pregnant travellers and their offspring are vulnerable to severe outcomes following a wide range of infections. Vaccine-preventable diseases can have a particularly severe course in pregnant women, but little is known about the safety of travel vaccines in pregnant women. We performed a systematic review of all published literature concerning the safety of vaccines frequently given to travellers such as yellow fever, MMR (mumps, measles and rubella), influenza, Tdap (tetanus, diphtheria and pertussis), meningococcus, hepatitis A and B, rabies, polio, typhoid fever, tick-borne encephalitis and Japanese encephalitis vaccines. We included case series, cohort studies and randomized controlled trials (RCTs). For the meta-analysis, we included only RCTs that compared the administration of a vaccine to placebo or to no vaccine. Outcome measures included severe systemic adverse events, maternal outcomes related to the course of pregnancy, neonatal outcomes and local adverse events. We calculated the risk ratio and its 95% confidence interval as the summary measure. The safety of influenza vaccine is supported by high-quality evidence. For Tdap vaccine, no evidence of any harm was found in the meta-analysis of RCTs. A slight increase in chorioamnionitis rate was reported in 3 out of 12 observational studies. However, this small possible risk is far outweighed by a much larger benefit in terms of infant morbidity and mortality. Meningococcal vaccines are probably safe during pregnancy, as supported by RCTs comparing meningococcal vaccines to other vaccines. Data from observational studies support the safety of hepatitis A, hepatitis B and rabies vaccines, as well as that of the live attenuated yellow fever vaccine. We found little or no data about the safety of polio, typhoid, Japanese encephalitis, tick-borne encephalitis and MMR vaccines during pregnancy.

Prevalence of Chronic Diseases among International Travelers Seeking Pretravel Medical Advice in 2018 at Malaga, Spain

Travelers with preexisting diseases or chronic conditions may be more susceptible to travel-related health risks. They may, therefore, require more attention from specialist travel medicine providers. Our objective was to examine a group of international travelers in Malaga, Spain, quantify the proportion of travelers suffering from chronic conditions, and understand the characteristics of this group. A representative sample of travelers requesting pretravel medical advice at one travel clinic were asked about their preexisting chronic conditions and any immunosuppression. Additional demographic variables were used in an analysis of bivariate correlations. We used a binary logistic regression analysis to identify relationships between independent variables (age, gender, type of trip, travel duration, and destination) and the presence or absence of chronic conditions in travelers. Of the sample of 1,196 travelers, 258 (21.6%) reported having preexisting chronic conditions and 72 (6%) had two or more chronic conditions. Twenty-four of the travelers with chronic conditions (9%) were immunocompromised because of the disease or treatment. The two most common chronic conditions were cardiovascular disease and chronic respiratory conditions (36.8% and 17.1%, respectively). The chronic condition increased by 6.7% for every year of increased age. Travelers with chronic conditions are older, travel mainly to visit friends and relatives, and take shorter trips. More than half of travelers visiting (55.8%) needed more attention from the travel medicine practitioner because of their preexisting chronic conditions, age, or type of travel. Surveillance data based on the population of people traveling would be helpful to provide better advice to travelers.

New guidelines for the prevention of imported malaria in France

Prevention of malaria is based on personal vector-control measures (PVCMs) to avoid mosquito bites at night and chemoprophylaxis if justified by the risk of contracting the disease. The most effective PVCM is the use of insecticide-treated mosquito nets. The decision to prescribe chemoprophylaxis, mainly to prevent Plasmodium falciparum infection, depends on the benefit-risk ratio. Overall, the risk of contracting malaria is 1,000-fold lower during a stay in the tropical regions of Asia or the Americas than in sub-Saharan Africa. For "conventional" stays (less than one month with nights spent in urban areas) in low-risk settings in tropical Asia and America, the risk of being infected with Plasmodium parasites (≤1/100,000) is equivalent or lower than that of experiencing serious adverse effects caused by chemoprophylaxis. Preventive medication is therefore no longer recommended. By contrast, in other settings and particularly in sub-Saharan Africa, chemoprophylaxis is the most effective measure against malaria. However, it is worth noting that no single preventive measure provides full protection. Regardless of the level of risk or chemoprophylaxis-related indication, protection against mosquito bites and rapid management of febrile illness after returning from an endemic area are also critical to prevent malaria. Finally, migrants of sub-Saharan origin visiting friends and relatives in their country of origin form a high-risk group who should be recommended chemoprophylaxis in the same way as any other travelers-with a preference for the least expensive molecules (doxycycline).

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.

Using Google Location History data to quantify fine-scale human mobility

Background

Human mobility is fundamental to understanding global issues in the health and social sciences such as disease spread and displacements from disasters and conflicts. Detailed mobility data across spatial and temporal scales are difficult to collect, however, with movements varying from short, repeated movements to work or school, to rare migratory movements across national borders. While typical sources of mobility data such as travel history surveys and GPS tracker data can inform different typologies of movement, almost no source of readily obtainable data can address all types of movement at once.

Methods

Here, we collect Google Location History (GLH) data and examine it as a novel source of information that could link fine scale mobility with rare, long distance and international trips, as it uniquely spans large temporal scales with high spatial granularity. These data are passively collected by Android smartphones, which reach increasingly broad audiences, becoming the most common operating system for accessing the Internet worldwide in 2017. We validate GLH data against GPS tracker data collected from Android users in the United Kingdom to assess the feasibility of using GLH data to inform human movement.

Results

We find that GLH data span very long temporal periods (over a year on average in our sample), are spatially equivalent to GPS tracker data within 100 m, and capture more international movement than survey data. We also find GLH data avoid compliance concerns seen with GPS trackers and bias in self-reported travel, as GLH is passively collected. We discuss some settings where GLH data could provide novel insights, including infrastructure planning, infectious disease control, and response to catastrophic events, and discuss advantages and disadvantages of using GLH data to inform human mobility patterns.

Conclusions

GLH data are a greatly underutilized and novel dataset for understanding human movement. While biases exist in populations with GLH data, Android phones are becoming the first and only device purchased to access the Internet and various web services in many middle and lower income settings, making these data increasingly appropriate for a wide range of scientific questions.

Electronic supplementary material

The online version of this article (10.1186/s12942-018-0150-z) contains supplementary material, which is available to authorized users.

Travel Characteristics and Pretravel Health Care Among Pregnant or Breastfeeding U.S. Women Preparing for International Travel

OBJECTIVE

To study characteristics and preventive interventions of adult pregnant and breastfeeding travelers seeking pretravel health care in the United States.

METHODS

This cross-sectional study analyzed data (2009-2014) of pregnant and breastfeeding travelers seen at U.S. travel clinics participating in Global TravEpiNet. Nonpregnant, nonbreastfeeding adult female travelers of childbearing age were used for comparison. We evaluated the prescription of malaria chemoprophylaxis and antibiotics for this population as well as the administration of three travel-related vaccines: hepatitis A, typhoid, and yellow fever. We also evaluated use of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis and influenza vaccines, because these are widely recommended in pregnancy.

RESULTS

Of 21,138 female travelers of childbearing age in Global TravEpiNet, 170 (0.8%) were pregnant and 139 (0.7%) were breastfeeding. Many traveled to destinations endemic for mosquito-borne illnesses, including malaria (pregnant: 95%; breastfeeding: 94%), dengue (pregnant: 87%; breastfeeding: 81%), or yellow fever (pregnant: 35%; breastfeeding: 50%). Compared with nonpregnant, nonbreastfeeding adult female travelers, eligible pregnant travelers were less likely to be vaccinated against hepatitis A (28% compared with 51%, P<.001) and typhoid (35% compared with 74%, P<.001). More than 20% of eligible pregnant travelers did not receive influenza vaccination. Yellow fever vaccine was occasionally provided to pregnant and breastfeeding travelers traveling to countries entirely endemic for yellow fever (6 [20%] of 30 pregnant travelers and 18 [46%] of 39 breastfeeding travelers). Half of pregnant travelers and two thirds of breastfeeding travelers preparing to travel to malaria-holoendemic countries received a prescription for malaria prophylaxis.

CONCLUSION

Most pregnant and breastfeeding travelers seen for pretravel health consultations traveled to destinations with high risk for vector-borne or other travel-related diseases. Destination-specific preventive interventions were frequently underused.

Guidelines for the prevention of travel-associated illness in older adults

International travel to the developing world is becoming more common in elderly patients (defined here as individuals greater than 65 years old). When providing pre-travel counseling, providers must appreciate the changing physiology, comorbidities, immunity and pharmacokinetics associated with the aging process to prepare elderly patients for the stressors of international travel. These guidelines present an evidence-based approach to pre-travel counseling, immunization, and pharmacology concerns unique to elderly patients seeking care in a travel clinic setting.

Pretravel Health Preparation of International Travelers: Results From the Boston Area Travel Medicine Network

Objective

To inform future interventions for advising travelers.

Patients and Methods

We prospectively collected data on travelers seen at the Boston Area Travel Medicine Network, a Boston area research collaboration of 5 travel medicine clinics. Data from 15,440 travelers were collected from March 1, 2008, through July 31, 2010. We compared traveler and trip characteristics and differences in demographic characteristics and travel plans across the 5 clinics, including an analysis of pretravel preparations for certain high-risk destinations.

Results

More than half of the 15,440 travelers were female (8730 [56.5]), and 72.4% (10,528 of 14,545) were white; the median age was 34 years, and 29.4% of travelers (3077 of 10,483) were seen less than 2 weeks before their departure date. Substantial variation in racial background, purpose of travel, and destination risk existed across the 5 clinics. For example, the proportion of travelers visiting friends and relatives ranged from 7.6% (184 of 2436) to 39.0% (1029 of 2639) (18.7% [2876 of 15,360] overall), and the percentage of travelers to areas with malaria risk ranged from 23.7% (333 of 1403) to 52.0% (1306 of 2512). Although most clinics were likely to have prescribed certain vaccines for high-risk destinations (eg, yellow fever for Ghana travel), there was wide variability in influenza vaccine use for China travel.

Conclusion

Substantial differences in clinic populations can occur within a single metropolitan area, highlighting why individual physicians and travel clinics need to understand the specific needs of the travelers they serve in addition to general travel medicine.

Travel During Pregnancy: Considerations for the Obstetric Provider

Importance

Travel among US citizens is becoming increasingly common, and travel during pregnancy is also speculated to be increasingly common. During pregnancy, the obstetric provider may be the first or only clinician approached with questions regarding travel.

Objective

In this review, we discuss the reasons women travel during pregnancy, medical considerations for long-haul air travel, destination-specific medical complications, and precautions for pregnant women to take both before travel and while abroad. To improve the quality of pretravel counseling for patients before or during pregnancy, we have created 2 tools: a guide for assessing the pregnant patient's risk during travel and a pretravel checklist for the obstetric provider.

Evidence Acquisition

A PubMed search for English-language publications about travel during pregnancy was performed using the search terms "travel" and "pregnancy" and was limited to those published since the year 2000. Studies on subtopics were not limited by year of publication.

Results

Eight review articles were identified. Three additional studies that analyzed data from travel clinics were found, and 2 studies reported on the frequency of international travel during pregnancy. Additional publications addressed air travel during pregnancy (10 reviews, 16 studies), high-altitude travel during pregnancy (5 reviews, 5 studies), and destination-specific illnesses in pregnant travelers.

Conclusions and Relevance

Travel during pregnancy including international travel is common. Pregnant travelers have unique travel-related and destination-specific risks. We review those risks and provide tools for obstetric providers to use in counseling pregnant travelers.