Jane N. Zuckerman

Knowledge, Attitudes and Practices in Travel-related Infectious Diseases: The European Airport Survey

BACKGROUND The European Travel Health Advisory Board conducted a cross-sectional pilot survey to evaluate current travel health knowledge, attitudes and practices (KAP) and to determine where travelers going to developing countries obtain travel health information, what information they receive, and what preventive travel health measures they employ. Subsequently, the questionnaire used was improved and a cross-sectional, multicenter study was undertaken in airports in Europe, Asia, South Africa and the United States. This paper describes the methods used everywhere, and results from the European airports. METHOD Between September 2002 and September 2003, 5,465 passengers residing in Europe and boarding an intercontinental flight to a developing country were surveyed at the departure gates of nine major airports in Europe. Questionnaires were self-administered, and checked for completeness and validated by trained interviewers. RESULTS Although the majority of travelers (73.3%) had sought general information about their destination prior to departure, only just over half of the responders (52.1%) had sought travel health advice. Tourists and people traveling for religious reasons had sought travel health advice more often, whereas travelers visiting friends and relatives were less likely to do so. Hepatitis A was perceived as the most probable among the infectious diseases investigated, followed by HIV and hepatitis B. In spite of a generally positive attitude towards vaccines, 58.4% and 68.7% of travelers could not report any protection against hepatitis A or hepatitis B, respectively. Only one in three travelers to a destination country with at least some malaria endemicity were carrying antimalarial drugs. Almost one in four travelers visiting a high-risk area had an inaccurate risk perception and even one in two going to a no-risk destination were unnecessarily concerned about malaria. CONCLUSIONS The large variation in destinations, age of the travelers and reasons for traveling illustrates that traveling to a developing country has become common practice. The results of this large-scale airport survey clearly demonstrate an important educational need among those traveling to risk destinations. Initiatives to improve such education should target all groups of travelers, including business travelers, those visiting friends and relatives, and the elderly. Additionally, travel health advice providers should continue their efforts to make travelers comply with the recommended travel health advice. Our common objective is to help travelers stay healthy while abroad, and consequently to also reduce the potential importation of infectious diseases and the consequent public health and other implications.

Travelers' Knowledge, Attitudes, and Practices on Prevention of Infectious Diseases: Results from a Pilot Study

BACKGROUND The European Travel Health Advisory Board conducted a cross-sectional pilot survey to evaluate current travel health knowledge, attitudes, and practice (KAP) and to determine where travelers going to developing countries obtain travel health information, what information they receive, and what preventive travel health measures they employ. METHOD Trained interviewers invited passengers at the departure gates of three international airports: London Heathrow, Paris Charles de Gaulle, and Munich to respond to a self-completion questionnaire. A total of 609 responses were collected. RESULTS The study showed that more than one-third of travelers questioned had not sought pretravel health advice and of those who did, over 20% sought advice 14 days or less prior to travel. One-third of the respondents were aged 50 or more, and 20% had planned their trip less than 2 weeks before leaving. Only a minority were able to demonstrate that they had been immunised as per the World Health Organization or national recommendations. Respondents often misperceived both the risk of malaria at the destination and recommended preventive measures. CONCLUSIONS The results of this pilot survey provided a valuable insight into the KAP of travelers and highlighted an important educational need among those traveling to risk destinations. Strategies are needed for raising awareness of preventable travel health issues and for raising compliance with existing recommendations.

The importance of injecting vaccines into muscle. Different patients need different needle sizes.

Most vaccines should be given via the intramuscular route into the deltoid or the anterolateral aspect of the thigh. This optimises the immunogenicity of the vaccine and minimises adverse reactions at the injection site. Recent studies have highlighted the importance of administering vaccines correctly.1–3 Clinical practice needs to reflect considerations about the right length and gauge of needles used to ensure that those vaccinated get the immunological benefit of the vaccines without local side effects. Injecting a vaccine into the layer of subcutaneous fat, where poor vascularity may result in slow mobilisation and processing of antigen, is a cause of vaccine failure1—for example in hepatitis B,2 rabies, and influenza vaccines.3 Compared with intramuscular administration, subcutaneous injection of hepatitis B vaccine leads to significantly lower seroconversion rates and more rapid decay of antibody response.1 Traditionally the buttocks were thought to be an appropriate site for vaccination, but …

A new accelerated vaccination schedule for rapid protection against hepatitis A and B

BACKGROUND Increasing travel stresses the requirement for rapid protection against infections such as hepatitis A and B. METHODS This randomised, multicentre study investigated an accelerated vaccination schedule using a combined hepatitis A and B vaccine (Twinrix, Smithkline Beecham Biologicals) compared with simultaneous administration of the two corresponding monovalent vaccines. The combined vaccine was administered on days 0, 7 and 21, whereas the comparison group received hepatitis A vaccine on day 0 and hepatitis B vaccine on days 0, 7 and 21. All subjects received booster vaccination at month 12. RESULTS At month 1, 100% of subjects in the combined group and 99% of the controls were seropositive for anti-HAV antibodies. The corresponding seroprotection rates for anti-HBs antibodies were 82.0 and 83.9%, respectively. Examination of the 95% confidence intervals (CIs) for the treatment differences showed the two vaccines to be equivalent in terms of immunogenicity 1 week after the initial vaccination course. Just prior to the booster, the seropositivity rate for anti-HAV was 96.2% in the combined group and 95% in the control group. For anti-HBs, this was 94 and 91.6%, respectively. All subjects were seropositive for anti-HAV and seroprotected against hepatitis B at month 13. The anti-HAV GMCs were 9571mIU/ml with the combined vaccine and 5206mIU/ml in control subjects. The anti-HBs titre was 26002 and 29,196mIU/ml, respectively. Both groups had a similar reactogenicity profile. CONCLUSIONS The accelerated schedule of the combined vaccine provides a good immune response against hepatitis A and B antigens and is suitable for last minute immunisation.

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.

Immunogenicity and reactogenicity of a group C meningococcal conjugate vaccine compared with a group A + C meningococcal polysaccharide vaccine in adolescents in a randomised observer-blind controlled trial.

This study evaluated the immunogenicity and reactogenicity of a group C meningococcal conjugate vaccine (MenC) compared with a group A+C meningococcal polysaccharide vaccine (MenPS) in healthy adolescents. Subjects were randomised to receive one dose of either MenC (n=92) or MenPS (n=90). Group C meningococcal IgG antibody concentrations and bactericidal titres were higher in the MenC group than the MenPS group at 1 month (22.8 U/ml vs 4.0 U/ml, p<0.001, and 87 vs 20, p<0.001, respectively) and 12 months (6.1 U/ml vs 3.0 U/ml, p<0.001, and 81.3 vs 20.2, p<0.001, respectively). No differences in post immunisation reaction rates were noted between the two vaccinated groups. This study demonstrated the safety and enhanced immunogenicity of the candidate meningococcal conjugate vaccine as compared with the licensed polysaccharide vaccine in adolescents.

Recent developments: Travel medicine

Travel medicine is an exciting interdisciplinary specialty that has developed rapidly in response to the needs of the travelling population worldwide. International arrivals worldwide by any form of transport were around 664 million in 2000 (fig ​(fig1),1), and the World Tourist Organisation has predicted an 80% increase in travel to long haul destinations between 1995 and 2010.1,2 Specialists in travel medicine consider diverse aspects of travel related health, including fitness to travel and the health risks of travelling in itself, as well as the implications of exposure to a variety of infectious diseases. This review highlights current topical issues in this evolving specialty. Figure 1 Percentage increase in international arrivals between 1993 and 19973

THE EPIDEMIOLOGY OF HEPATITIS B

Although the history of epidemic jaundice can be traced to the Babylonian Talmud (5th-century bc) and Hippocrates (460–375 bc), the history of serum hepatitis (hepatitis B) is much shorter, with the earliest recognized outbreak among Bremen shipyard workers in 1883. The wide-scale introduction and common use of large syringes and long needles with the 1909 advent of salvarsan therapy in venereal disease clinics was soon followed by sudden outbreaks of jaundice. 23 During World War II (1939–1945), hepatitis became a serious problem in certain clinics. Large numbers of patients had venepunctures and received subcutaneous, intramuscular or intravenous injections. This was the case in diabetic clinics, sanatoria, arthritis clinics, and venereal disease treatment clinics for service personnel. On investigation, it was found that the incidence of hepatitis tended to be low in venereal disease clinics where the syringes were sterilized between patients, whereas it tended to be high in clinics where the syringes were merely washed. 10 The term homologous serum jaundice was introduced in Britain after the publication of a Ministry of Health Memorandum 11 describing the outbreak of jaundice and deaths that followed the subcutaneous administration of measles convalescent serum to children, which also had been recorded as early as 1938. Jaundice associated with immunization against yellow fever was recognized in 1937, but the largest outbreak of serum hepatitis (hepatitis B) was in 1942, when 28,585 American soldiers inoculated with yellow fever vaccine developed jaundice, and 62 died. 8 There was considerable evidence that the hepatitis was caused by a filterable agent present in the human serum and incorporated in the virus culture medium used for the preparation of the vaccine. Jaundice became recognized after the transfusion of plasma, reconstituted serum, 12 or whole blood. 1 The term hepatitis A, for infectious or epidemic hepatitis, and hepatitis B, for serum hepatitis or homologous serum jaundice, were introduced by MacCallum in 1947 9 and adopted by the Scientific Group on Viral Hepatitis of the World Health Organization in 1973. Blumbergs 2 discovery of the specific association of Australia antigen (hepatitis B surface antigen [HBsAg]) with hepatitis provided a specific serologic test for hepatitis B and a method of diagnosis and study of the epidemiology and prevention of this common and important infection. The rapid development of specific and sensitive laboratory tests of markers of infection with hepatitis B virus (HBV) provided the means of differentiating between hepatitis A and hepatitis B other than by the incubation period, confirmed the existence of the carrier state estimated conservatively to number 350 million carriers worldwide, identified the infection in every population studied, provided evidence that one third of the world population had been infected with this virus, with 1 to 2 million deaths annually, and identified the common modes of transmission of HBV. Much has been written during the last 3 decades on the complex epidemiology of hepatitis B, and an enormous bibliography has been accumulated on the subject. 5,6,7,20

Cholera: assessing the risk to travellers and identifying methods of protection

This review is based on the findings of a consultation meeting involving consultants in travel medicine and focusing on the risks of cholera to the traveller. Cholera is a severe diarrhoeal disease transmitted via the faeco-oral route and commonly associated with poor sanitation. Between the years of 1995 and 2001, the WHO reported 1829 cases of cholera in developed countries, the majority of which were imported. However, it is believed that this figure reflects less than 10% of the true incidence of cholera due to milder cases being unrecognised, as well as significant underreporting. Travellers to epidemic countries may be at increased risk of contracting cholera if they ingest contaminated food or water. It has been estimated that there are 0.2 cases of cholera per 100,000 European and North American travellers, though there is some evidence that this rate is higher. Oral vaccines are a necessary and welcome advance as, in addition to preventing illness, they can minimise the possibility of transmission of cholera to disease-free regions. The morbidity from cholera can range from asymptomatic or oligosymptomatic infection to disruption of holiday and business plans, or even severe toxicity and dehydration. If untreated, severe illnesses can be fatal, although fatalities have not been reported among travellers for many years.

Immunogenicity and safety of an experimental adjuvanted hepatitis B candidate vaccine in liver transplant patients

Patients with chronic liver disease are at higher risk of hepatitis B (HB) virus infection before and after liver transplantation, and they commonly have a suboptimal immune response to HB vaccines. In this randomized trial, we compared the immunogenicity of primary vaccination with 2 doses of an experimental adjuvanted HB vaccine (adjuvant system 04 containing aluminium and monophosphoryl lipid A [HB‐AS04]) to that of 3 double doses of a licensed HB vaccine in 93 liver transplant candidates. Depending on the waiting list for liver transplantation, a booster dose of HB‐AS04 or double booster dose of the licensed HB vaccine was given before or after surgery, at 6 to 12 months after initiation of the vaccination course. The percentage of subjects with seroprotective anti‐HB surface antibody concentrations 1 month after booster was twice as high in the HB‐AS04 group (60.0%), vs. patients in the comparator group (32.0%) (P = 0.035). In subjects who did not undergo liver transplantation before administration of the booster, better immunogenicity results were obtained: 80% of subjects were seroprotected after HB‐AS04 vaccination vs. 60% with the comparator (P = 0.2302). Despite a slightly higher reactogenicity, the safety profile of the HB‐AS04 vaccine was clinically acceptable. In conclusion, an improved antibody response was observed in liver transplant candidates with 3 doses of HB‐AS04, as compared to 4 double doses of a comparator. Liver transplant candidates could benefit from the use of this experimental adjuvanted HB vaccine to further increase their protection against HB infection. Liver Transpl 12:1489‐1495, 2006.