What do travellers know about malaria?

Connaissances et perceptions du paludisme chez 103 voyageurs à destination intertropicale consultant le centre de conseil aux voyageurs du centre hospitalier universitaire de Bordeaux, France

OBJECTIVE

Malaria is increasing worldwide due to the emergence and spread of drug resistant strains. As globalization in business and commerce and appetites for more adventurous travel increase, more people from non-endemic countries are being exposed to malaria. The management of travelers before departure or returning from visiting endemic countries with malaria is a challenge, both for exposed individuals and for physicians, considering the weak knowledge of the disease.

METHODS

A survey was conducted among French individuals traveling to endemic areas to evaluate their knowledge and perception of malaria. An observational study using guided questionnaires was made on 103 travelers recruited in the Bordeaux University Hospital travel clinic, France.

RESULTS

The findings of the survey were consistent with previously reported data concerning the knowledge of signs and symptoms of malaria, as well as with the global level of knowledge on the disease, and with the number of travelers not understanding the mode of infection appropriately. Irrelevant data was reported concerning the typical pattern of the disease, the objectives of malaria management for travelers, and the attention given to the most susceptible groups: children, pregnant women, and immuno-compromised individuals.

CONCLUSION

Our findings show a link between gender and adhesion to prophylactic measures, and an inverse gradient in the subgroup of frequent overseas travelers, between knowledge and risk perception of illness.

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 anti-mosquito 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 post travel, 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.

The prevention of malaria

Long before the advent of modern chemoprophylaxis drugs, many practitioners successfully prevented the debilitating and fatal outcomes associated with infection by the Plasmodium parasites that cause malaria. Today, with effective insect repellents and several excellent medications available for chemoprophylaxis, there has never been a better array of quality products to prevent mosquito bites and infection and to suppress parasites once in the blood stream; however, there are thousands of imported cases into nonendemic countries and scores of deaths and near-fatal outcomes every year in returning travelers, soldiers, immigrants, and refugees. In this article, the author focuses on practical uses of currently available prevention tools.

Feasibility of a rapid dipstick antigen-capture assay for self-testing of travellers' malaria

This open comparative study sought to determine whether, and with what level of instruction, travellers can successfully use and interpret the rapid whole blood malaria diagnostic test, ParaSight F. 160 visitors to the Zürich University Travel Clinic took part in the study. One group received written instructions only, while another group was given combined oral and written instructions on how to test their own blood for malaria infection and interpret a series of 5 prepared test strips. Each volunteer also completed a questionnaire targeted at assessing performance in using the diagnostic, interpretation of the results and acceptability of the concept of self-testing for malaria infection. The main outcome measures were successful performance of the test, correct interpretation of prepared test strips and acceptability of the test. In the group which received only written instructions, 60/80 (75%) were successful, whilst in the group which received written and oral instructions, 72/80 (90%) successfully performed the test (P < 0.02). Overall, 565 (70.6%) test strips were correctly and 165 (20.6%) incorrectly interpreted with 113 (14.1%) false negative interpretations. No prepared test strip was interpreted as false positive. Seventy (8.8%) test strips were not interpreted. Some 91. 9% of all candidates would use such a test if it were available. While it is possible for lay persons to successfully perform the test, interpretation of results poses a problem. In particular, the proportion of false negative interpretations is unacceptable. A combination of written and oral instructions leads to a significantly higher level of successful test performance. If such a test is to be made available to the general public, written instructions must be made concise and foolproof and the test endpoint clearly defined, as the currently available test is more suitable for trained laboratory personnel. In the meantime other candidate diagnostics have become available and these should now be assessed for their suitability in the context of travellers' malaria.

Risk of malaria in visitors to the Kruger National Park, South Africa

BACKGROUND

The risk of malaria to visitors to South Africa's nature reserves is unknown. Current recommendations for travelers are based on malaria incidence rates in local communities. These rates may well overestimate travelers' malaria risk and lead to unnecessary use of antimalarial prophylaxis with associated drug-related adverse events. This study investigated the incidence of malaria in visitors to South Africa's Kruger National Park (KNP).

METHODS

Postal questionnaires were sent to the cohort of visitors staying in the KNP during April 1996, 6 to 8 weeks after they returned to their homes. Nonrespondents received duplicate questionnaires 8 weeks later. Responses from 3267 groups, representing 11,107 visitors (56. 8%) allowed determination of the malaria attack rate in this group of travelers and assessment of associations between malaria risk and a number of factors, including type of accommodation used during the visit; duration of stay; use of chemoprophylaxis; and use of personal protection measures. All travelers indicating that they had suffered an episode of malaria following their visit were telephonically contacted and their health providers traced to determine the basis of diagnosis and clinical outcome.

RESULTS

One clinically suspected and four confirmed cases of Plasmodium falciparum malaria among the visitors suggest a low attack rate of 4. 5 cases per 10,000 visitors during April, the highest risk month for malaria in South Africa. No association was found between malaria risk and accommodation type, duration of stay, use and type of chemoprophylaxis, and use and number of personal protection measures.

CONCLUSIONS

These findings confirm the importance of careful assessment of local malaria risk before individualized advice is provided to travelers.

Epidemiology and awareness of malaria in the Lothians

Awareness of malaria and its presentation could be improved. Awareness of symptoms, incubation periods and route of transmission was poor, as was compliance with prophylaxis. The mean difference between the time to admission and the time to presentation was 2.9 days which reflects medical rather than patient associated delay.

Specialized Travel Consultation Part I: Travelers' Prior Knowledge

Studies have shown that more than one third of all travelers to tropical countries experience an illness while abroad. Naiveté about diseases, such as malaria, travelers' diarrhea, cholera, and HIV infections, appears to be the most crucial factor determining travel-related morbidity rates. A study was designed both to evaluate the level of disease-related, pretravel knowledge prior to a specialized travel clinic consultation as well as to correlate the level of knowledge with demographic and travel variables and previous travel experience. Using a self-administered questionnaire, data were collected from 167 clients who attended the Hospital for Tropical Diseases Travel Clinic, London, England, in June 1991. The questionnaire evaluated clients' knowledge and attitudes of travel-related diseases, their prevention and treatment, and the scores were analyzed using the Statistical Analysis System software, Version 5. Predictors for increased knowledge scores were examined by a one-way layout model comparing disease knowledge scores with variables such as sex, age, socioeconomic class, ethnic background, previous travel experience, type and duration of travel, destination, accommodation quality, and health insurance coverage. A step-down regression model was constructed to control for the effects of the many mutually confounding factors. Travelers' diarrhea and malaria risk at destination were acknowledged by more than 85% of the respondents, and 60% of the questions on travelers' diarrhea prevention, compared to 81% of those on malaria prevention, were answered correctly. Significantly, however, only one half of the respondents indicated that they would take appropriate measures concerning diarrhea while abroad. Stepwise regression identified previous travel experience, pretravel advice, traveling for work purposes, and using backpack overland tours as significant predictors of high knowledge. This study points out the necessity of pretravel education and that it should focus not only on malaria but also on other travel-related diseases like travelers' diarrhea. As well, target groups for whom more detailed information should be provided are identified, including inexperienced travelers, those using organized tours and sleeping indoors, those planning to visit friends or relatives, and those who have not received sufficient pretravel health advice.

Travellers' malaria

The risk of malaria poses travellers and their advisers with difficult problems as drug resistance spreads worldwide. Protection against infection rests on travellers' knowledge of the risk of malaria, on their avoidance of malaria vectors and on their compliant use of chemoprophylaxis. In this article, Robert Ste f fen and Ronald Behrens explain that one of the priorities for reducing malaria morbidity is to improve travellers' use of personal protection against mosquito bites. They show that none of the drugs, or combinations thereof, provide a 100% efficacy, owing to increasing drug resistance, mainly of Plasmodium falciparum. The commonly used drugs for malaria prophylaxis (mefloquine, doxycycline, chloroquine and proguanil) often cause minor side effects. All, except proguanil, have also been occasionally associated with severe adverse effects. Other drugs (pyrimethaminelsul fadoxine, amodioquine) are not suitable for chemoprophylaxis because of unacceptable adverse reactions. The use of drugs for self therapy is constrained by limitations of toxicity and efficacy, and the added difficulties of defining indications for safe and appropriate use.

Surgical aspects of malaria

The spread of drug-resistant organisms and increased international travel makes malaria a disorder of ever-increasing importance. This report reviews those aspects of malaria of surgical relevance. The importance of the spleen in host defence against malaria and other infections makes splenic preservation desirable whenever possible after rupture of the spleen. Tropical splenomegaly is caused by an abnormal immune response to malaria and is best managed medically. Careful selection of blood donors is essential to prevent transfusion malaria, and routine antimalarial prophylaxis is indicated for blood recipients in many endemic areas. The risk of postoperative malaria may justify chemoprophylaxis in certain patients.