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Replacement of lost cranial bone (partly mesodermal and partly neural crest‐derived) is challenging and includes the use of nonviable allografts. To revitalize allografts, bone marrow‐derived mesenchymal stromal cells (mesoderm‐derived BM‐MSCs) have been used with limited success. We hypothesize that coating of allografts with induced neural crest cell‐mesenchymal progenitor cells (iNCC‐MPCs) improves implant‐to‐bone integration in mouse cranial defects. Human induced pluripotent stem cells were reprogramed from dermal fibroblasts, differentiated to iNCCs and then to iNCC‐MPCs. BM‐MSCs were used as reference. Cells were labeled with luciferase (Luc2) and characterized for MSC consensus markers expression, differentiation, and risk of cellular transformation. A calvarial defect was created in non‐obese diabetic/severe combined immunodeficiency (NOD/SCID) mice and allografts were implanted, with or without cell coating. Bioluminescence imaging (BLI), microcomputed tomography (μCT), histology, immunofluorescence, and biomechanical tests were performed. Characterization of iNCC‐MPC‐Luc2 vs BM‐MSC‐Luc2 showed no difference in MSC markers expression and differentiation in vitro. In vivo, BLI indicated survival of both cell types for at least 8 weeks. At week 8, μCT analysis showed enhanced structural parameters in the iNCC‐MPC‐Luc2 group and increased bone volume in the BM‐MSC‐Luc2 group compared to controls. Histology demonstrated improved integration of iNCC‐MPC‐Luc2 allografts compared to BM‐MSC‐Luc2 group and controls. Human osteocalcin and collagen type 1 were detected at the allograft‐host interphase in cell‐seeded groups. The iNCC‐MPC‐Luc2 group also demonstrated improved biomechanical properties compared to BM‐MSC‐Luc2 implants and cell‐free controls. Our results show an improved integration of iNCC‐MPC‐Luc2‐coated allografts compared to BM‐MSC‐Luc2 and controls, suggesting the use of iNCC‐MPCs as potential cell source for cranial bone repair., Bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) were obtained from human bone marrow. Induced neural crest cell‐mesenchymal progenitor cells (iNCC‐MPCs) were generated from induced pluripotent stem cell‐derived iNCCs. Cells were luciferase transfected and seeded onto decellularized allografts, which were implanted into 5 mm circular calvarial defects in non‐obese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Allograft only was used as controls. Mice were followed for a duration of 8 weeks. Cell survival, allograft integration, and tissue morphology and transplanted cell contribution were monitored via bioluminescence imaging (BLI), micro‐computed tomography (μCT), and histology and immunofluorescence (IF). Green arrow: BLI; yellow arrow: μCT; Orange arrow: histology and IF; Blue arrow: biomechanical test.

Background The Hajj is one of the world’s largest pilgrimage and gathers millions of Muslims from different nationalities every year. Communicable diseases have been reported frequently, during and following the Hajj, and these have been linked to individual behavioural measures. This study aimed to measure the effect of personal preventive measures, such as face mask use, hand hygiene and others, adopted by pilgrims in reducing the acquisition of infectious diseases. Methods We conducted a cross-sectional study at the Hajj terminal in King Abdulaziz International Airport in Jeddah, Saudi Arabia. Pilgrims were approached in the airport lounges after the 2017 Hajj season and prior to the departure of their flights from Jeddah to their home countries. An electronic data collection tool (‘Open Data Kit’) was used to gather survey data in regards to health problems and preventive measures during the Hajj. Results A total of 2973 Hajj pilgrims were surveyed. In all, 38.7% reported symptoms of upper respiratory tract infections (URTIs) and 5.4% reported symptoms of travel diarrhoea. Compliance with face mask use was 50.2%. Changing a face mask every 4 h was found to be significantly associated with lower prevalence of URTIs [adjusted odds ratio 0.56 (95% confidence interval 0.34–0.92), P = 0.02]. There was no statistical difference between overall face mask use and URTI acquisition. The main sources of food, eating raw vegetables/food, frequency of hand washing or use of hand sanitizers were not found to be significantly associated with reported travellers’ diarrhoea. Unlicensed barbers were used by 12% of pilgrims and 9.2% of pilgrims reported using blades that were reused by other pilgrims. Conclusion Preventive measures are the most effective way to prevent infections. Pilgrims can benefit from face masks by changing them frequently. There is still limited information on the effect of the use of face mask in decreasing the risk of URTI in mass gatherings.

Background Existing travel health guidelines are based on a variety of data with underpinning evidence ranging from high‐quality randomized controlled trials to best estimates from expert opinion. For strategic guidance and to set overall priorities, data about average risk are useful. The World Health Organization (WHO) plans to base future editions of “International Travel and Health” on its new “Handbook for Guideline Development.” Methods Based on a systematic search in PubMed, the existing evidence and quality of data on vaccine‐preventable disease (VPD) risks in travelers was examined and essentials of vaccine efficacy were briefly reviewed. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework was used to evaluate the quality of the data. Results Moderate‐quality data to determine the risk of VPD exist on those that are frequently imported, whereas in most others the level of confidence with existing data is low or very low. Conclusions In order for the WHO to produce graded risk statements in the updated version of “International Travel and Health,” major investment of time plus additional high‐quality, generalizable risk data are needed.

The recommendation for carriage standby emergency treatment (SBET) for malaria is now becoming more widespread across Europe. This follows as a replacement to the withdrawal of recommendations for use of malaria chemoprophylaxis, predominantly therefore to falling transmission of Plasmodium falciparum malaria on the successful malaria control programmes across South East Asia and South America.1 Travellers are prescribed SBET antimalarial medication to carry during their journey. The policy is aimed at travel to areas of low falciparum malaria transmission in the above continents, not at travellers to Sub Saharan Africa. They are advised to use the medication when malaria is suspected and prompt medical attention is unavailable, but ideally, to attend a medical centre within 24 h of onset of symptoms for a diagnosis, and if malaria is confirmed, use the medication secure in the knowledge that it is not counterfeit.

Background Despite many travelers receiving at least one vaccination during the pre-travel consultation, little is known about travelers' fear of injections and the impact this may have on educating travelers about health risks associated with their trip. This study aimed to investigate: (1) the prevalence of injection anxiety in travelers attending a pre-travel consultation, (2) whether anxiety due to anticipating a vaccination adversely affects recall of information and advice, and (3) whether clinicians can recognize travelers' anxiety, and how they respond to anxious travelers. Methods Consecutive adult travelers (N = 105) attending one of two inner-city travel clinics completed self-report measures of state anxiety, injection anxiety, and symptoms of needle phobia immediately before and after their pre-travel consultation. Clinicians were also asked to rate travelers' anxiety and report any anxiety management strategies. Standardized information was presented during the consultation and recall of information and advice was assessed immediately post-consultation. Delayed recall (24 hours) was assessed for a subsample (20%) of participants. Results More than one third of travelers reported feeling nervous or afraid when having an injection (39%). Travelers' state anxiety was related to their psychological and physiological reactions to needles, and reduced significantly post-consultation. Recall of information and advice varied, with failure of recall ranging from 2 to 70% across 15 items, and delayed recall being significantly lower. No relationship was found between recall and anxiety. Clinician-rated anxiety moderately correlated with travelers' self-reported anxiety. Conclusions A significant proportion of travelers experienced injection anxiety when attending the pre-travel consultation, with some travelers reporting symptoms consistent with criteria for Blood Injection Injury phobia. There were important gaps in recall of information and advice about common travel risks. Although no relationship was found between recall and anxiety, this may have been due to the sample and setting.

Background A patch vaccine containing heat-labile toxin (LT) from enterotoxigenic Escherichia coli (ETEC) has demonstrated to be beneficial in reducing the rate and severity of travelers' diarrhea in Latin America. To evaluate the efficacy of this transdermal vaccine system in an area with a different diarrheal pathogen profile, an additional phase 2 study was conducted in European travelers to India. Methods For this multicenter, randomized, double-blinded, placebo-controlled field study 723 subjects were recruited; 603 (299 LT vaccine, 304 placebo) were included in the per-protocol-population (PPP). Results Although the LT patch induced a measurable LT immune response in recipients, it failed to protect against LT ETEC or all-cause diarrhea. In the PPP the incidence rate of diarrhea as per primary endpoint was 6.0% (18 of 299) in the vaccine group and 5.9% (18 of 304) in the placebo group. Additionally, lower than expected rates of LT ETEC diarrheas were observed in India. The vaccine delivery system frequently produced rash and pruritus at the site of application, long term hyperpigmentation persisted in a minority of LT recipients, and also few site reactions were noted in the placebo group. Conclusions The evaluated patch vaccine failed to satisfy mainly with respect to protective efficacy. Noninvasive prophylactic agents against travelers' diarrhea, particularly vaccines against the most frequent pathogens, thus continue to be badly needed.

Background Accessible travel has led to a rapid growth in international tourism, particularly to developing countries. With the increase, travel-associated morbidity and mortality has changed. Data on traveling populations are essential for policy makers to estimate infectious and noninfectious risks in travelers. Passenger flow statistics are compiled by the World Tourism Organization (WTO) and by official institutions of some countries. This study investigates sources of passenger flow statistics, methods of data collection, and compares datasets for consistency. Methods Four national datasets of departing travelers were compared to the United Nations' World Tourism Organization (WTO) data on passenger arrivals to eight destination countries. The ratio between arrivals and departures was calculated (main destination ratio [MDR]) to estimate the proportion of direct to indirect traveler arrivals. Results With few exceptions, arrival data exceeded that of departure data for all destinations. India is a primary destination for Australian residents where arrival and departure figures were similar (MDR 1.1), while visits to Cambodia and Turkey, with 3.6- and 3.8-fold higher arrivals, respectively, are part of multidestination trips. For UK residents, arrivals exceeded departures for all destinations except India where the reverse was true (MDR 0.8). A close correlation between arrivals and departures was noted for visits to South Africa while arrivals to Singapore and Cambodia were 7- and 10-fold higher, respectively. Arrivals by Finnish residents to destination countries were 1.4- to 1.6-fold higher than departures and 2.2-fold higher for Canadians visiting China. Conclusions Different methodologies used to capture arrival and departure statistics result in different estimations of traveler numbers. Data from a single source does not provide a comprehensive picture of most tourism itineraries. Inbound statistics give a more accurate reflection of the total visits made by travelers from a source country.

Imported malaria has been described as “an infection that was acquired in an endemic area by an individual (either a tourist or indigenous native) but diagnosed in a non‐endemic country after development of the clinical disease.” 1 In the UK, there was an average of 1,965 laboratory‐confirmed reports of imported malaria infections between 1987 and 2006, 2 and this country, together with France, Germany, and Italy, accounts for about three‐quarters of the 10,000 to 12,000 annual cases imported into the World Health Organization European region. 3 The majority of imported malaria infections reported in European countries are caused by Plasmodium falciparum , 3 the Plasmodium species associated with the most severe disease and mortality. Data from TropNetEurop, 4,5 a European sentinel surveillance system, describe how most cases originate from West Africa and affect travelers of African ethnicity. The most commonly reported reason for travel is to visit friends and relatives (VFRs), with 64.5% of all travelers citing this as a reason for travel in malaria reports between 1987 and 2006 to the UK's Malaria Reference Laboratory and 76.4% in reports to TropNetEurop in 2007. 5 Those VFRs who were born and lived for some time in malaria‐endemic countries before moving to Europe will have acquired partial immunity from exposure to malaria during childhood. Without repeated exposure, immunity appears to wane with time, although the time period during which this occurs is unknown. Bouchaud and colleagues 6 have demonstrated that levels of parasitemia and severe disease were lower in African migrants who were resident outside malarious areas for more than 4 years but acquired falciparum malaria on a short visit to a malaria‐endemic area, when compared to patients who had always lived outside these areas. However, a recent study of African migrants in Italy 7suggests that living for more than … Corresponding Author: Penny Neave, MSc, Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK. E‐mail: penny.neave{at}lshtm.ac.uk

Background. Travel-associated health risks need to be balanced against the positive opportunities associated with interregional travel. As the perceived and real spectrum of health risks related to international travel increase both quantitatively and qualitatively, the need for more discriminating tools in clinical assessment for the purpose of mitigation, public health management, and research are needed. One group of international travelers identified as having increased risk of poor travel-related health outcomes are those who travel with the specific intent of visiting friends or relatives (VFR travelers). Due to variations in defining VFR travel in the health context there are issues in applying this designation uniformly from multiple perspectives. This article supports the standardization of VFR traveler definitions based on objective criteria and provides illustrations of the application of this definition through an illustrated approach to risk assessment based on these criteria and the differentials in the determinants of health between source and destination regions. Methods. A working group was established by the Migration Health Sub-committee, International Society for Travel Medicine to assess the literature on VFR travel and health, review an evidence-based approach to managing health risk related to travel, and to propose criteria-based definition for VFR travel. The new definition of a VFR is a traveler whose primary purpose of travel is to visit friends or relatives where there is a gradient of epidemiological risk between home and destination. Results. A case scenario discussion of VFR travel defined by criteria and risk assessment based on differential determinants of health is presented in this article. Discussion. The goal of this article is to encourage discussion on travel health evaluation for the most ‘‘at risk’’ populations and to standardize the application of clinical, public health, and research approaches to defining VFR travelers in a risk management context.

BACKGROUND: Large numbers of Western travelers visit countries endemic for Japanese encephalitis (JE). The risk of infection is unknown. This study attempts at estimating a risk incidence for visitors from two European countries with the available data. METHODS: Using the total number of case reports between 1978 and 2008, the number of visits made by European tourists to endemic regions, and total doses of vaccines sold in the two study countries, the risk incidence of JE in travelers was estimated. The proportion of vaccinated visitors to endemic regions was retrieved from the data of two travel clinics (in London and Basel) and related to vaccine prescribing in UK and Swiss travelers. RESULTS: In 2004, an estimated 0.16% to 0.3% of UK and Swiss travelers were vaccinated against JE, with no surveillance reports of JE cases. Between 116,000 and 152,000 European travelers would receive vaccination. More than 99% travel to endemic countries without vaccination. Only 40 cases of JE infection have been reported in travelers for the past 30 years. The risk incidence is thus 1.3 per year in 7.1 million visits of the 17 million European travelers who are at a potential risk of JE infection. CONCLUSIONS: This study and the analysis of the existing literature support the recommendation that all travelers should be informed about the risk of JE infection but also suggest that there is no evidence for justifying a general recommendation for JE vaccination in travelers to endemic areas.

BACKGROUND: The main aims of this study were to quantify the annual risk of falciparum malaria among nonimmune, UK-based airline crew and to undertake a risk assessment of short layovers in sub-Saharan African cities. METHODS: The number of nights exposed in malaria-endemic regions and reported cases of falciparum malaria were used to estimate annual disease incidence. Transmission risk estimates were calculated for each layover, that is, where crew were accommodated overnight, for one or more nights, in designated city hotels. Air-conditioning of ground transport, hotels, and airports was provided at all crew layovers. Details of activities associated with a risk for malaria and of adherence to antimosquito measures among crew were collected through a self-administered postal questionnaire. RESULTS: The annual risk of falciparum malaria was calculated to be 1.6 cases per 100,000 nights of exposure (95% CI 0.5-3.7). Crew reported widespread use of personal protection measures during the evenings when at risk. CONCLUSIONS: Attack rates of falciparum malaria were considerably lower than those reported in tourists during visits to sub-Saharan Africa. Factors contributing to this low attack rate included risk awareness, a protected sleeping environment, an urban setting, vector environmental controls, brief exposure, and good compliance with personal protection measures. Previously reported chemoprophylaxis compliance of < 10% in the same population was unlikely to have contributed to the low rate of disease. The longer layovers, of 3 or 4 nights, in some East African rosters provided greater opportunity for discretionary leisure activity away from protected hotel environments, and this needs to be considered in a risk assessment.

BACKGROUND: Travel associated malaria is a major health risk for visitors to malaria endemic destinations. To examine the knowledge of malaria prevention, risk perception, current prophylactic behavior, and compliance with chemoprophylaxis and personal and environmental protection measures we conducted a study in a cohort of travelers exiting Zimbabwe from two international airports during a peak malaria transmission period. METHODS: Data were collected by pretested self-administered questionnaires from 595 adults in the departure lounges of Harare and Victoria Falls International airports. Excluded were children and travelers from the African continent. A multilingual research assistant supervised data collection. RESULTS: The majority of travelers obtained health advice prior to travel. Patterns of protective behavior and compliance with prophylaxis were inconsistent with a high perception of malaria threat and good knowledge. About 23% of travelers failed to use chemoprophylaxis during their visit. In the group of travelers who used chemoprophylaxis, 18% were noncompliant. Fifteen drug combinations were in use. Full compliance with medication plus use of personal preventive measures always was estimated as 13%. Forgetfulness was the main cause of noncompliance, followed by deliberate omission due to side effects. Of 57 travelers who reported side effects from current medication, over half used mefloquine. CONCLUSIONS: There is a need to examine how people process personal risk and communications about risk. We must recognize the competition between precautionary measures against malaria and other life demands that are imposed by travel, especially in young long stay travelers and persons visiting primarily for business purposes. Mediating a protective response will also depend on judgments about the effectiveness of the action, strengthening travelers intentions toward adherence, and increasing efficacy perception by individuals and their peers. Conflicts in prophylactic recommendations need to be resolved. As ecotourism develops in Zimbabwe and other malaria regions, stakeholders in this rapidly growing industry must be made aware of the important role they can play in protecting clients from malaria.

Concerns about the tolerability of mefloquine highlight the need for new drugs to prevent malaria. Atovaquone-proguanil (Malarone; GlaxoSmithKline) was safe and effective for prevention of falciparum malaria in lifelong residents of malaria-endemic countries, but experience in nonimmune people is limited. In a randomized, double-blind study, nonimmune travelers received malaria prophylaxis with atovaquone-proguanil (493 subjects) or mefloquine (483 subjects). Information about adverse events (AEs) and potential episodes of malaria was obtained 7, 28, and 60 days after travel. AEs were reported by an equivalent proportion of subjects who had received atovaquone-proguanil or mefloquine (71.4% versus 67.3%; difference, 4.1%; 95% confidence interval, -1.71 to 9.9). Subjects who received atovaquone-proguanil had fewer treatment-related neuropsychiatric AEs (14% versus 29%; P=.001), fewer AEs of moderate or severe intensity (10% versus 19%; P=.001), and fewer AEs that caused prophylaxis to be discontinued (1.2% versus 5.0%; P=.001), compared with subjects who received melfoquine. No confirmed diagnoses of malaria occurred in either group. Atovaquone-proguanil was better tolerated than was mefloquine, and it was similarly effective for malaria prophylaxis in nonimmune travelers.

Background: In the UK, travel health advice is mainly provided by practice nurses and general practitioners (GPs). The need for their improved education in travel medicine has been highlighted through previous studies and by an increasing number of requests for training. Methods: A questionnaire-based survey of 3900 GP practices was conducted to assess training requirements and to establish the demand for an academic course in travel medicine. 1430 (37%) questionnaires were completed. Results: 93% of practices provided a pretravel advice service. 87% of GPs advised an average of 10 travelers per month and only 48% immunized travelers. 98% of nurses advised and immunized an average of 28 travelers a month. 21% of GPs and two-thirds of nurses had attended one or more training sessions in travel medicine. Over 90% of the sample (83% of GPs and 98% of nurses) expressed an interest in attending a formal training program in travel medicine. Eligibility for Post Graduate Education Awards (PGEA) was important for most GPs (88%). Nurses valued approval by the English National Board for Nursing (88%) and a system of Credit Accumulation & Transfer (CATS) (82%). Funding for a course would be met in full by 18% of respondents (mainly GPs) and a further 20% would contribute to fees. Most GPs and nurses have ready access to a range of information sources, e.g., a postgraduate medical centre (85%) and a medical library (91%). Computerized access to information was feasible as 93% had a computer and 54% had a modem attached. Conclusions: The discipline of travel medicine is becoming increasingly specialized. Future practitioners will need to enhance their skills to meet the demands of today's travelers. Our results show that general practice staff are keen to develop such skills. Specialist training courses need to be expanded to meet this demand.

The development of oral rehydration therapy (ORT) has resulted in clear and practical methods for replacing fluid and electrolyte losses during diarrhoea. Rehydration salts can be provided in 3 ways; a pre-packed, easy to use, package which requires controlled formulation and distribution, a cereal-based formula from widely available ingredients which require preparation and cooking, or a home-made recipe of sugar with salt, which is relatively easily prepared. Poor retention of knowledge on the correct way to prepare solutions, inadequate availability of ingredients and practical problems of home production are major problems in ORT programmes. Although ORT may be life saving in severe dehydrating diarrhoea, it may not have an impact on milder illness, dysentery or persistent diarrhoea. Breast feeding is a natural and effective method for preventing and reducing diarrhoeal morbidity and its role needs repeated promotion. Early feeding in diarrhoea reduces duration, severity and adverse nutritional sequelae. The benefit of vitamin A and folic acid supplements are as yet unproved; zinc may have a role in aiding recovery of malnourished children. Drug treatment should be limited to parasitic gut infections, cholera or dysenteric disease. Widespread prescribing of drugs for diarrhoea by health workers may be hindering the success of ORT.

Malaria continues to be a serious health risk for travellers. The malaria parasites which infect humans can only be naturally transmitted by female mosquitoes of the genus Anopheles. Travellers to malaria endemic areas require detailed advice on appropriate chemoprophylaxis against malaria and personal protection against mosquito bites. The decision on an appropriate chemoprophylaxis or standby therapy regimen should reflect the malaria risk, pattern of drug resistance, and the toxicity of available drugs. Currently travellers encounter a number of problems in protecting themselves against malaria. Advice is often both inadequate and inaccurate; and all the recommended drug regimens are associated with minor, and occasionally major adverse reactions. Because of poor compliance to drug prophylaxis and to reduce the impact of drug resistance, protection against mosquitoes has a critical role in protecting travellers from malaria. Compliance to methods of personal protection not only reduces the malaria risk but also limits the nuisance and loss of sleep from biting insects.

Much effort and resources have been focused on improving or evolving antimalarial prophylactic regimens in order to reduce the increasing problems of malaria infection in nonimmune travelers to malaria endemic regions. Falciparum malaria in travelers returned from Africa has been attributed to reduced efficacy of chloroquine against chloroquine-resistant strains of Plasmodium falciparum (CRPF). Reported prophylaxis use by tourists from East Africa suggests only 52% admit taking their chemoprophylaxis without any missed doses. The effect of noncompliance with chloroquine (CQ) or proguanil (PG) in East Africa has been estimated as equivalent to taking no prophylaxis at all. The influence of poor compliance and/or parasite resistance on the changing pattern of malaria among travelers needs to be understood if methods of reducing morbidity are to be identified. In a number of studies, prophylaxis compliance in travelers has been collected by self-administered questionnaires from which prophylaxis efficacy of drug regimens has been calculated. The interpretation of drug efficacy has hinged on drug compliance and is controversial. We have addressed the role of chemoprophylaxis compliance in travelers with malaria using a prospective study of 368 malaria patients attending the Hospital for Tropical Diseases by examining their travel history and reported prophylaxis compliance compared to their actual plasma drug levels. This has enabled us to characterize the role of CRPF and poor compliance in the etiology of breakthrough malaria in travelers.

With an increase in travel to tropical countries, the need to improve the disease-risk perceptions of travelers who are either naive or given inappropriate or ineffective advice is becoming increasingly important. More widely available, specialized centers that can provide advice on tropical or travel-related diseases have been established, but their efficacy on travelers' knowledge and health has not been verified. Therefore, this study was undertaken to evaluate the impact of the service provided by a routine travel consultation at the Hospital for Tropical Diseases Travel Clinic, London, England. Self-administered questionnaires were given to 161 preconsultation and 144 postconsultation clients. The consultation included an interview covering travel plans and immunization and medical history, and advice was given on the journey, necessary immunizations, and prophylaxis. Data were analyzed using the Statistical Analytic System software and the mean differences in knowledge between pre- and postconsultation scores were correlated using the nonparametric Mann-Whitney procedure. The control of mutually confounding factors was maintained by multiple regression using the Mantel-Haenszel summary chi-square and the General Linear Model procedures. Comparison of the entry and exit scores showed a significantly improved overall knowledge of travel-related diseases in the exit, postconsultation group. Subanalysis revealed that this difference was due to an increased knowledge of malaria and its prevention and perceived risk of cholera. Knowledge about the management of diarrhea or fever, however, was not significantly improved by a consultation. Inexperienced travelers taking packaged or organized trips, and those from socioeconomic groups I and II showed the largest increase in knowledge following consultation. Our results show that a face-to-face interview for an average of 18 minutes by trained staff is an effective way of improving travelers' knowledge on certain topics. The slight improvements overall are explained by the levels of experience of travel and previously acquired knowledge of the clients in our study. Effective advice on malaria prevention and some health risks is given during an average consultation; however, there is still a need for improvement in giving information on the management of diarrhea, fever, and other travel diseases.

The potential for traveller's diarrhoea to impair proguanil and chloroquine absorption and cause chemoprophylaxis failure was investigated in a study involving recently returned travellers who were either asymptomatic or presented with diarrhoea. A routine dose of chemoprophylaxis was administered to 12 travellers with diarrhoea and 12 asymptomatic subjects. The subjects undertook a lactulose-mannitol intestinal permeability test and were bled hourly after prophylaxis ingestion. Plasma analysis of chloroquine and proguanil from serial samples revealed a significantly lower proguanil Cmax (146 ng/mL vs. 196 ng/mL, P = 0.05), and longer tmax (3.1 h vs. 2.6 h, P = 0.05) in the diarrhoea cohorts. The absorption coefficient was lower for proguanil (0.57 vs. 0.76) but the difference did not quite reach levels of significance. Chloroquine kinetics were similar in both groups. The diarrhoea cohort had a three-fold higher lactulose absorption, influencing the mean lactulose mannitol:ratio, 0.114 +/- 0.17 compared to the control ratio of 0.02 +/- 0.01 (P = 0.04). Symptomatic subjects had impaired mucosal function which reduced the absorption of proguanil but not chloroquine, a phenomenon which may reduce prophylactic efficacy.

Until recent political events, Kenya was a popular tourist destination for European and North American travelers. The International Health Regulations 1 consider Kenya as an area or country with risk of yellow fever transmission as the vector and primary host are present. The World Health Organization (WHO) with a number of national bodies recommends that all visitors to the country receive yellow fever vaccine on the basis that yellow fever transmission can occur and all travelers should be protected. 2As a result of this pragmatic policy, many travelers from Western Europe and North America to Kenya are immunized against … Corresponding Author: Ronald H. Behrens, MD, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK. E‐mail: ron.behrens{at}lshtm.ac.uk

To the Editor‐in‐Chief: Derek Smith and Peter Leggat 1write in their editorial of the need to increase access to, and readership of, specialist subjects …

Chloroquine-resistant Plasmodium vivax was originally reported in Papua, New Guinea by Reickman in 1989.1 In the same year, in Colombia, South America, Arias and Corredor2 reported relapses of 11 patients suffering from vivax malaria, following a chloroquine-primaquine regimen. Garavelli and Corti3 suggested chloroquine-resistant Plasmodium vivax may be present in Brazil following these therapeutic relapses. Further therapeutic failures in returned travelers from South America were reported by Moore et al (1994).4 We report vivax malaria in a group of expeditioners visiting Guyana who, whereas compliant with antimalarial chemoprophylaxis, developed clinical malaria, adding evidence to the presence of chloroquine-resistant Plasmodium vivax in South America. Raleigh International is a youth development charity that undertakes environmental and community projects around the world. These are usually in remote locations. Nine expeditions in countries such as Chile, Belize, Zimbabwe, Uganda, and Malaysia are organized annually. A project manager and a medical officer are placed at each site, along with approximately 10 venturers (age 17-25.) Participants are of all nationalities, but, at present, they are predominantly British.