Risk of Hepatitis B for Travelers: Is Vaccination for All Travelers Really Necessary?

Objectives.  Behavioral studies in travelers suggest that 33% to 76% of all travelers to hepatitis B virus (HBV)–endemic countries are at risk for HBV infection. We study the incidence and risk factors for HBV infection in travelers.
Methods.  Retrospective analysis of the characteristics and risk factors of all reported acute HBV patients in Amsterdam, the Netherlands, from January 1, 1992, until December 31, 2003.
Results.  The estimated incidence in travelers from Amsterdam to HBV-endemic countries is 4.5/100,000 travelers. Two thirds of these patients were immigrants who lived in Amsterdam and who had visited their friends and relatives in their country of origin. In 12 years, only three Dutch short-term tourists contracted HBV while traveling, all by heterosexual contacts.
Conclusions.  Dutch tourists who travel to HBV-endemic countries run a very low risk of contracting HBV. Vaccination of short-term Dutch tourists is not necessary. Immigrants run a higher risk irrespective of travel or duration of travel. This group should be advised vaccination.     

Imported typhoid fever in Switzerland, 1993 to 2004

Background.  In industrialized countries, typhoid fever occurs mainly in returned travelers. To determine the need for preventive strategies, eg, for vaccination, continuous monitoring is needed to assess where the risk for travelers is highest.
Methods.  To investigate where the risk for travelers to acquire typhoid fever is highest, 208 patients with typhoid fever and recent travel were matched with travelers' statistics collected by the Swiss Federal Office of Statistics.
Results.  At the beginning of the study period, up to 30 infections with Salmonella typhi were recorded per year in Switzerland. Since 2001, less than 15 confirmed cases per year occurred. A majority of the 208 (88.5%) typhoid cases were associated with recent travel. Countries with highest risk were Pakistan (24 per 100,000), Cambodia (20 per 100,000), Nepal (14 per 100,000), India (12 per 100,000), and Sri Lanka (9 per 100,000).
Conclusions.  We found that over a 12-year period (1993–2004), the travel-associated risk of typhoid fever is highest for destinations in the Indian subcontinent. All other regions showed a decline, most markedly in southern Europe. Our results suggest that typhoid fever vaccination should be recommended for all travelers to countries in South Asia. Otherwise, vaccination of tourists to frequently visited low- and intermediate-risk areas is not necessary, unless there are behavioral risk factors.     

Pretravel advice and hepatitis A immunization among Australian travelers

BACKGROUND: More Australians are traveling to overseas destinations where preventable infectious diseases, such as hepatitis A, are endemic. Yet, there is only limited data concerning the extent to which Australians seek travel advice and vaccination before their departures. METHOD: Annual telephone surveys were conducted among adult Australians travelers. Information was collected on the travel advice and vaccinations received before departure. Perceptions about, and their potential exposure to, travel-related infections while overseas were also assessed. This paper presents data from the 2003 survey related to travel advice and hepatitis A, while hepatitis B is discussed in the companion article. RESULTS: Only a third of interviewees had sought health advice before travel. Infrequent travelers, those departing for endemic countries or for longer journeys, were more likely to seek medical advice. Overall, 32% of interviewees had been vaccinated against hepatitis A, with travelers to high/medium-hepatitis A endemicity destinations being more likely to be vaccinated than those visiting low-endemicity countries (44% vs 20%). Among the 263 visitors to endemic countries, those who stayed with friends and relatives were least likely to be vaccinated against hepatitis A compared to other styles of accommodation. CONCLUSIONS: Despite government recommendations and industry group campaigns about the need for pretravel advice, the majority of Australians travel overseas without adequate health advice and protection against hepatitis A and other travel-related infectious diseases.     

Tuberculosis risk in US Peace Corps Volunteers, 1996 to 2005

Background.  With the popularity of international travel increasing, more travelers in endemic areas may increase their risk of tuberculosis (TB). We analyzed Peace Corps data to assess the risk of TB in long-term travelers from the United States.
Methods.  We analyzed purified protein derivative (PPD) conversion and acute TB case data from the Peace Corps Epidemiological Surveillance System as well as postservice claims data. We calculated the risk of PPD conversion and active TB in all countries with Peace Corps Volunteers between 1996 and 2005 and compared these risks with other published data.
Results.  The overall incidence rates for positive PPD conversions and active TB cases are 1.283 and 0.057 per 1,000 Volunteer-months, respectively. The Africa region had the highest PPD conversion rate of 1.467 conversions per 1,000 Volunteer-months as well as the highest active TB rate of 0.089 cases per 1,000 Volunteer-months. Per-country incidence rates for PPD conversions and active TB cases ranged widely from 0.000 to 5.514 cases and 0.000 to 2.126 cases per 1,000 Volunteer-months, respectively. In countries identified as "high risk," there were 1.436 cases of PPD conversions and 0.084 cases of active TB per 1,000 Volunteer-months.
Conclusions.  Peace Corps Volunteers have significantly higher rates of TB when compared to the average US population but much lower than those reported for travelers to highly endemic countries. Volunteers assigned to highly endemic countries still have a lower risk compared to other travelers to those same countries. Keeping in mind that Peace Corps Volunteers are a unique population, these data may be useful in providing medical advice to long-term travelers.     

Risk Estimates of Dengue in Travelers to Dengue Endemic Areas Using Mathematical Models

Background.  Dengue has emerged as a frequent problem in international travelers. The risk depends on destination, duration, and season of travel. However, data to quantify the true risk for travelers to acquire dengue are lacking.
Methods.  We used mathematical models to estimate the risk of nonimmune persons to acquire dengue when traveling to Singapore. From the force of infection, we calculated the risk of dengue dependent on duration of stay and season of arrival.
Results.  Our data highlight that the risk for nonimmune travelers to acquire dengue in Singapore is substantial but varies greatly with seasons and epidemic cycles. For instance, for a traveler who stays in Singapore for 1 week during the high dengue season in 2005, the risk of acquiring dengue was 0.17%, but it was only 0.00423% during the low season in a nonepidemic year such as 2002.
Discussion.  Risk estimates based on mathematical modeling will help the travel medicine provider give better evidence-based advice for travelers to dengue endemic countries.     

Hepatitis A Risk in Travelers

Background.  Traveling to highly endemic areas for hepatitis A is increasing while the immunization level in travelers has been shown to be low in the countries studied.
Methods.  In this population-based study, we have estimated the incidence rate of travel-related hepatitis A during 1997 to 2005 by use of the Swedish notification system of communicable diseases and an ongoing national database on travel patterns. We have also acquired airport-based immunization data from 2007.
Results.  During the study period, 636 cases of travel-related hepatitis A were notified. Traveling to East Africa was associated with the highest incidence rate (14.1 cases/100,000 person months), followed by the Middle East (5.8/100,000 person months), and India with neighboring countries (5.6/100,000 person months). Visiting Friends and Relatives (VFR) travelers represented 83, 91, and 70% of the cases to these three regions. By age-group, the highest incidence was found in children 0 to 14 years (3.1/100,000 travelers) where 88% of the cases were VFR travelers. Incidence rate in unprotected travelers to East Asia, North Africa, and the Middle East was 2, 12, and 18 cases/100,000 person months, respectively. In 2007, 79% of the travelers were immunized against hepatitis A.
Conclusions.  We conclude that travelers, and especially children, who are VFR in endemic areas constitute a high-risk group for acquiring hepatitis A infection, while the risk for unprotected tourists to East Asia is low.     

Cost–Benefit of WC/rBS Oral Cholera Vaccine for Vaccination Against ETEC-Caused Travelers' Diarrhea

Background.  The most common infectious health problem encountered by travelers to countries in the developing region is travelers' diarrhea (TD), with enterotoxigenic Escherichia coli (ETEC) being the most common pathogen isolated. Although mild in most cases, the disease still leads to the loss of a significant part of a vacation or business trip. There is currently a lack of knowledge about the costs in relation to the benefits of vaccination against TD caused by ETEC, and the purposes of this study were to estimate and develop a cost-benefit analysis of vaccination using whole-cell/recombinant-B-subunit oral cholera vaccine.
Methods.  The consequences of the vaccination were identified and quantified in monetary terms. The cost–benefits for leisure and business travelers were assessed separately. The value of the travel was separated into the cost of the trip and of lost leisure time/business opportunities. A person with TD was in base case estimated to lose on average 3.5 days of a 7-day leisure trip and 2.5 days of a 4-day business trip. Results are presented for a Canadian traveler to endemic areas in year 2007 in US$.
Results.  The average cost of a TD event was estimated at $1,460 and $1,996 for leisure and business travelers, respectively. The net value of the vaccination, however, varied with the risk of the disease. Through extensive literature searches, an updated ETEC map illustrating the proportion of ETEC-caused TD was created.
Conclusions.  The analysis indicated that vaccination would be considered cost-effective at incidence rates of ETEC-caused TD above about 13 and 9% for leisure and business travelers, respectively. It is, however, important to keep in mind that it is the value of the travel for the individual traveler that will decide if the vaccination provides good value for money.     

Meningococcal Disease in Travelers: Vaccination Recommendations

Background : The object of the study was to determine the incidence rate of meningococcal disease in travelers originating in industrialized countries and visiting developing countries. Subjects were intercontinental travelers with meningococcal disease acquired from 1986 to 1989.
Method : Health authorities in 108 countries were contacted; data obtained by postal survey were analyzed.
Results : The 56 replying health authorities reported 13 cases of meningococcal disease in tourists or business persons as well as 40 primary and 26 secondary cases in pilgrims to Mecca. The majority of cases were due to serogroup A. The case fatality rate in both groups of patients slightly exceeded 20%. Among the tourists and business persons, several patients had stayed in hotels; in several the onset of symptoms occurred during the flight home. The incidence rate per month of stay was estimated to be 0.4 per million travelers in this group, but 2000 per million in pilgrims to Mecca.
Conclusion : Vaccination of pilgrims to Mecca is highly recommended, presently even compulsory. For the usual traveler to endemic countries, the risk of infection abroad seems not to exceed the one at home, thus vaccination may be limited to high-risk groups, such as trekkers.     

Knowledge, Attitudes and Practices of Business Travelers Regarding Malaria Risk and Prevention

Background This study aimed to determine the knowledge, attitudes and practices of Swiss business travelers with regard to malaria.
Methods Questionnaires printed in three languages were distributed by employers, travel agencies and tropical medicine specialists to business travelers with destinations in malaria endemic countries.
Results In total, 401 questionnaires were evaluated. Thirty-three percent visited high-risk areas, 27% visited low-risk areas, and 40% visited only malaria-free areas within endemic countries. Among the investigated business travelers, 6% had experienced malaria infection, and 29% had previously had blood smears tested for malaria at least once. Almost all business travelers, 95%, knew that mosquitoes are the main vectors of malaria. The infection risk between dusk and dawn was known to 71%, and the incubation time to 36%. Apart from fever (99%) and headache (63%), other malaria symptoms were known to only 13% to 36% of the travelers. If signs of illness such as fever and headache occurred, 63% would react adequately and seek medical advice within 24 h. Only 16% of the travelers to African high-risk areas followed the recommended behavior concerning antimosquito and antimalarial strategies; 31% of those on trips to low-risk areas used an adequate protective strategy. Of the business travelers using chemoprophylaxis during travel, just 50% continued intake posttravel, as requested, after leaving the endemic area.
Conclusions Business travelers are well informed regarding the mode of transmission and the risk of malaria at specific destinations but tend to comply poorly with anti-mosquito and chemoprophylactic strategies. The knowledge, attitudes and practices of business travelers with regard to malaria prevention need to be improved.     

Recommendations for Prevention of Hepatitis A Based on a Cost-Effectiveness Analysis

Background . Hepatitis A viral infection poses a substantial risk for travelers from low-endemic countries visiting high-endemic destinations. In this study, the general indications for the optimal prevention of hepatitis A are derived using a cost-effectiveness analysis based on the risk exposure determined by frequency and duration of travel as well as natural immunity.
Methods . Three possible hepatitis A prevention strategies are compared to no prophylaxis: active immunization; an initial screening for HAV followed by active immunization of susceptible travelers; and passive immunization with immune globulins. Using a number of baseline assumptions, a scenario for travel from low- to high-endemic countries and an average travel duration and frequency rate, threshold values were obtained comparing active versus passive immunization.
Results . The study shows that, for travelers not expected to journey more than twice in a 10-year period, passive immunization is the most cost-effective prophylaxis for travel from both very-low or low-to-high endemic areas. For more frequent travel, vaccination is more cost effective, as well as for journeys of 6-months' duration or longer. As well, pretravel screening before vaccination was shown to be worthwhile, except when the probability of natural immunity is low.
Conclusions . As the results indicate, the cost effectiveness of a strategy is related to several considerations: the prices of vaccine and screening tests, travel destinations and endemic conditions, frequency and duration of travel, and natural immunity. A decision-tree-based simulation model is helpful in determining the strategy to employ.     

The Risk of Malaria in Travelers to India

Background.  Several countries have reported a decline in malaria cases imported by travelers returning from India.
Methods.  We collected data on imported malaria for the period 1992 to 2005 from nine countries. Traveler statistics denominator data were obtained from the Indian Ministry of   Tourism.
Results.  The malaria case numbers declined from 93 cases per 100,000 travelers in 1992 to 19 cases per 100,000 travelers in 2005. The proportion of Plasmodium falciparum decreased steadily throughout the years. The proportion of Plasmodium vivax accounts for more than 80% of all cases of malaria in travelers to India. Deaths due to malaria were rare; only the UK and the United States reported deaths, a total of 16, between 1992 and 2005. The high-risk areas for malaria in India can be clearly identified using endemic malaria data. High-risk states are Chhattisgarh, Orissa, Jharkhand, West Bengal, Goa (mainly P vivax ), and the states east of Bangladesh.
Conclusions.  The decreasing incidence of malaria in travelers to India and the high proportion of P vivax support the current change in guidelines in some European countries advocating the use of the standby emergency self-treatment strategy or bite precautions plus awareness of risk instead of chemoprophylaxis. Otherwise in high-risk states, chemoprophylaxis should still be considered particularly in high-transmission seasons.     

Imported Histoplasmosis: Two Distinct Profiles in Travelers and Immigrants

Background.  Histoplasmosis is acquiring importance in nonendemic areas due to the increase in travel and immigration, being the most common systemic mycosis acquired by European travelers. Epidemiological studies show that the incidence of Histoplasma infection in these patients may be higher than previously believed and a wide clinical spectrum of disease may be observed.
Methods.  Cases of histoplasmosis diagnosed at a Tropical Medicine Referral Unit in Madrid, Spain, during the period January 1996 to December 2006 were reviewed.
Results.  Ten cases of histoplasmosis in travelers and immigrants are described. Five HIV-positive patients (four immigrants and one expatriate) all presented with progressive disseminated disease. Five HIV-negative patients (travelers) all presented with pulmonary disease: four with an acute pulmonary form (one with pleural involvement) and one patient was found to have residual pulmonary disease (lung nodule). Three of the travelers also had rheumatologic manifestations (arthromyalgias or arthritis).
Conclusions.  Clinicians in nonendemic areas may be faced with patients with a diagnosis of histoplasmosis and although Histoplasma infection can have a varied and nonspecific clinical presentation, imported histoplasmosis may have two distinct profiles. Previously, healthy travelers may be exposed in endemic areas and mainly develop acute forms of the disease with a favorable outcome. Immigrants or expatriates from endemic areas who may be immunosuppressed due to HIV infection may experience reactivation of latent disease developing disseminated forms with high mortality rates. This infection should be considered in the differential diagnosis of diseases affecting travelers and immigrants.     

Overseas Outbreaks of Infectious Intestinal Disease Identified in Scotland, 2003 to 2007

Background.  This article presents information on all potential outbreaks of infectious intestinal disease (IID) identified by Health Protection Scotland (HPS) involving residents of Scotland. Unlike other systems, this alert system covers potential outbreaks of IID rather than apparently sporadic cases and covers all gastrointestinal pathogens, all visited countries, and all groups of travelers.
Methods.  HPS collects information on all potential outbreaks of IID in residents of Scotland where infection is believed to have been acquired abroad and disseminates this to all public health teams in Scotland so other linked cases can be identified. Where possible HPS also disseminates the details to the national surveillance center in the country where infection is believed to have been acquired, enabling them to facilitate any investigations or control measures they believe necessary. The rate of outbreaks associated with travel to particular countries was determined using the number of visits reported for residents of Scotland from Travel Trends data from the Office of National Statistics.
Results.  Between 2003 and 2007, 319 such potential outbreaks were identified. Spain was the most frequently identified country reflecting the fact that it was also the most frequently visited country; the rate per 100,000 visits to Spain was 1.4, very similar to the overall rate for all countries of 1.3, while the highest rate of 46.7 per 100,000 visitors was associated with travel to Egypt. Salmonella sp was the most frequently identified pathogen within which Salmonella enteritidis was the most frequently identified serotype.
Conclusions.  The system provides a rapid alert mechanism for potential outbreaks of IID outside Scotland, allowing their investigation and control as appropriate and demonstrates the risks of outbreaks associated with different countries and pathogens.     

Japanese encephalitis for a reference to international travelers

Japanese encephalitis (JE) is an inflammatory disease in the central nervous system caused by infection with Japanese encephalitis virus (JEV). JE is a disease with a high fatality rate and endemic and epidemic in East, Southeast, and South Asia. High morbidity is noted in children living in the endemic area. JEV is maintained mainly between vector mosquitoes and pigs in nature. The risk of JE increases as the number of vector mosquitoes increases. The expansion of JEV-endemic area depends on irrigated rice field and pig farming. These environments that are suitable for infectious cycle of JEV exist widely in Asia today. The effective and safe vaccine is available in endemic countries and for international travelers. JE vaccination is strongly recommended to those who visit the JEV-endemic regions, especially in the rainy season.     

Hepatitis B risks and immunization coverage among American travelers

BACKGROUND: Hepatitis B is endemic in much of Asia, Africa, and parts of South America, regions that are increasingly popular destinations for American travelers. The frequency of hepatitis B risks during travel has been examined for Europeans but not Americans. Further, limited data are available to describe the domestic hepatitis B risk factors of American travelers, the proportion vaccinated, and whether immunization activities target travelers at highest risk. We conducted a survey of international travelers to address these issues. METHODS: A survey was mailed to 884 American international travelers, of whom 618 (70%) responded. The survey covered demographic and travel characteristics, sources of pre-travel health advice, immunization status, and items needed to assess hepatitis B vaccination candidacy. Travel-specific items concerned the most recent trip to a hepatitis B endemic region. Hepatitis B risk during the most recent trip was classified as high, potential, or none based on potential exposure to blood or bodily fluids. RESULTS: Only 31% of respondents visited any health practitioner to obtain pre-travel health advice; 13% visited a travel medicine specialist. Totally 45% of respondents reported (3)1 domestic or travel-related hepatitis B risk, and 8% were at high risk during travel. Risk factors were more common among younger travelers and those with longer travel durations. Travel medicine specialists were more likely than nonspecialists to provide hepatitis B vaccine (40% vs 21%, p= 0.01). Travelers with risk factors were no more likely to be vaccinated in specialist or nonspecialist settings. Upon departure, only 19% of all travelers and 30% of travelers with risk factors had received three or more hepatitis B vaccine doses. CONCLUSIONS: Most US travelers to hepatitis B endemic regions do not secure pre-travel health advice, and most have not received three doses of hepatitis B vaccine. A substantial share are candidates for hepatitis B vaccination based on their domestic activities, and/or face hepatitis B risks during travel.     

Malaria Prophylaxis in Different Age Groups

Background: There is a perceived increased health risk in senior visitors to malaria endemic countries.
Methods: The authors sought to compare effectiveness and tolerability of malaria chemoprophylaxis in senior travelers (≥60 years) with those in younger travelers (20–59 years). The "Malpro 2" database consists of more than 100,000 questionnaires completed by travelers on charter planes returning from East Africa to Europe during July 1988-December 1991. Among them, 9106 (9.1%) of the travelers were 60 years or older, and 84,562 (84.6%) of the travelers reported to be 20–59 years. Variables of demography, travel data, and the effectiveness and tolerability of chemoprophylaxis were compared in the two subgroups.
Results: Malaria in Africa was reported by 8 (1/1000) elderly travelers and by 189 (2.2/1000) travelers aged 20–59 years. Adjusting for age, sex, prophylaxis, and duration of stay in Africa in a logistic regression model, malaria was significantly more frequent in younger than in senior travelers (p<.05). Any travel-associated illness was reported by 7.0% in the senior age group and by 13.6% in the younger age group (p<.05). The rates of travelers who indicated they had "side effects" attributable to malaria prophylaxis varied between 9.7% in the elderly and 15.5% in the younger travelers (p<.05).
Conclusion: Senior travelers tolerate malaria chemoprophylaxis and visits to the tropics at least as well as younger travelers.     

Risk of Cholera Among Western and Japanese Travelers

Background : There has been concern about an increased risk of cholera in travelers to Latin America since the spread of the pandemic to this part of the world. Additionally, before this study the continuous high incidence of imported cholera to Japan had so far not been analyzed.
Methods : A retrospective analysis of cases notified in 1991 to national surveillance centers in industrialized countries and to the World Health Organization was carried out. Denominator data were obtained by the World Tourism Organization.
Results : The reported rate of imported cholera in European and North American travelers visiting endemic areas remains in the range of 0,2 per 100,000, as was observed 10 years ago. This rate is, however, is manyfold higher in Japanese travelers, with a highest value of 13,0 per 100,000 reported in those returning from Indonesia, usually Bali. No secondary outbreaks were observed in those countries to which cholera was imported.
Conclusions : It is assumed that the higher rates in Japanese travelers are mainly due to more intensive surveillance. On Bali and elsewhere, further studies are needed to determine both the role of V. cholerae as a cause of traveler's diarrhea in tourists and to re-evaluate the need for cholera vaccination at specific high-risk destinations.     

Knowledge, Attitudes, and Practices of French Travelers from Marseille Regarding Rabies Risk and Prevention

Objective.  To assess the awareness of the mode of rabies transmission, travel-associated rabies risk, and adequate preventive measures among French travelers.
Methods.  Three hundred travelers were administered a detailed questionnaire prior to pretravel advice, addressing their knowledge, attitudes, and practices (KAP) with respect to animal-related injuries and rabies risk. Two hundred and nine were administered a post-travel questionnaire by telephone, addressing the occurrence of contacts with animals during travel.
Results.  Countries visited were at risk for rabies in 84.7% of the cases. Only 6.7% of travelers knew that the risk of rabies was important, while 40.1% considered it moderate or low. Dog bites appeared to be a well-known mode of transmission of rabies. By contrast, licks on broken skin or contamination of the mucous membrane with saliva (10%) and scratches (0.7%) were rarely known. Cats (23.7%), foxes (28.3%), monkeys (10.3%), and bats (5.0%) were rarely mentioned as possible rabies vectors. Only 50.7% of travelers were aware of the preventive vaccination. Approximately 57.6% of individuals traveling to rabies–endemic countries presented to the clinic less than 21 days before departing, rendering a complete preventive vaccination against rabies unfeasible. Immediate washing of the injury with water and soap was mentioned by only 3.0% of individuals and self-disinfection with antiseptics by 21.3%. Of those who traveled in a rabies-risk country, 3.8% declared that they had been attacked by animals; however, none was injured. Animal encounters were frequent with dogs (53.8%), monkeys (39.5%), bats (17.9%), and cats (15.4%).
Conclusions.  The KAP of French travelers with regard to travel-associated rabies risk need to be improved, particularly regarding the prevention of animal bites, postbite measures, and their urgency.     

Overseas Visitor Deaths in Australia, 2001 to 2003

Background.  The health and safety of international visitors remain an important issue for Australia and other tourist destinations. The death of visitors remains an important indicator of safety. The aim of this study was to provide updated figures on deaths of overseas travelers in Australia.
Methods.  Data were sourced from the Australian Bureau of Statistics concerning deaths of overseas visitors for the years 2001 to 2003.
Results.  There were 1,068 overseas visitor deaths (701 males, 66%) during the study period 2001 to 2003. Death by natural causes increased with age, while deaths associated with accidents were more frequent among younger age groups. The majority of deaths were from natural causes (782, 73%), particularly ischemic heart diseases (26%). There were a total of 247 accidental deaths (23% of all deaths) with the main causes being transportation accidents (14% of all deaths) and accidental drowning/submersion (5% of all deaths). The countries contributing the most deaths were the UK (247, 23%), New Zealand (108, 10%) Melanesia/Micronesia (95, 9%), and the United States (57, 5%).
Conclusions.  Australia remains a relatively safe destination for international travelers, at least in terms of fatalities, which appear to be declining. Most deaths of overseas tourists in Australia are due to natural causes with cardiovascular disease being the predominant cause of death in this group. Accidents remain the most common preventable cause of death of travelers, with road and water safety being the major issues. It is important that tourism and travel medicine groups continue to advocate for improved health and safety of international travelers visiting Australia.     

Risks of hepatitis B in travelers as compared to immunization status

BACKGROUND: Our objective was to determine the risks of infection with hepatitis B among European travelers and to compare this with the immunization status in various risk groups. METHODS: A cross-sectional telephone questionnaire survey of randomly selected subjects, in nine European study populations was used. A total of 9, 008 individuals were involved, with approximately 1,000 interviews conducted in each country in the native languages. Situations with a high risk of hepatitis B infection, such as invasive medical procedures, attending to a bleeding person, and skin perforating cosmetic practices, particularly when performed in countries with medium/high transmission risk, and vaccination status of travelers, were the main outcome measures. RESULTS: Depending upon the destination, 6.6-11.2% of travelers were classified as at high risk of hepatitis B, with 24.4% vaccinated; between 60.8-75.8% of travelers at potential risk, with 19.2% vaccinated; and 33.4% of travelers where no hepatitis B risk was identified. Significantly more travelers who only visited medium/high endemicity regions exposed themselves to a high risk of contracting hepatitis B, (40, 10.5%) compared to travelers who only visited low endemicity regions (225, 6.6%; p <.01). CONCLUSIONS: A significant proportion of travelers surveyed unwittingly exposed themselves to the risk of hepatitis B infection while at medium/high risk destinations. The majority of at-risk travelers had not been vaccinated, regardless of their destination. Improved advice and clear recommendations to avoid transmission are needed.