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Background: Malaria parasites that carry the DHFR-mutation I164L are not only highly resistant to sulfadoxine-pyrimethamine but also to the new antimalarial drug chlorproguanil-dapsone. The spread of this mutation in Africa would result in a public health disaster since there is a lack of effective alternatives that are both affordable and safe. Up to now, this mutation has only been described in Asian and Latin-American countries. The objective of this study was to assess the prevalence of this mutation in African isolates of Plasmodium falciparum that have been imported into Europe through travellers. Methods: TropNetEurop is a network for the surveillance of travel-associated diseases and seems to cover approximately 12% of all malaria cases imported into Europe. Within this network we screened 277 imported African isolates of P. falciparum with the help of PCR- and enzymedigestion-methods for the antifolate-resistant mutation I164L. Results: The I164L mutation was not detected in any of the isolates tested. Discussion: Continuous molecular surveillance of mutations in P. falciparum, as it is practised within TropNetEurop, is an essential tool for the understanding and early detection of the spread of antimalarial drug resistance in Africa. [ABSTRACT FROM AUTHOR]

Malarone® (atovaquone-proguanil) is an effective drug for the treatment and prophylaxis of multidrug-resistant falciparum malaria. However, first cases of resistance have been reported, which are associated with mutations at codon 268 of the parasite's cytochrome b gene. We report the first case of Malarone® treatment failure from Central Africa. Drug concentration was well within curative range. Pre- and post-treatment Plasmodium falciparum isolates revealed codon 268 wild-type alleles, and no other mutations of the putative atovaquonebinding domain. These findings illustrate the spread of atovaquone-proguanil-resistance in Africa and question the usefulness of codon 268 as the only target for the surveillance of its emergence. [ABSTRACT FROM AUTHOR]

Background. Cutaneous myiasis is frequently reported in patients from tropical countries. Most commonly infestation is due to Cordylobia anthropophage and Dermatobia hominis, whereas Hypoderma lineatum is less likely to affect humans. Methods. The clinical and parasitologic aspects in a series of 13 patients with cutaneous myiasis seen in a German travel clinic are reviewed. Results. Six patients were infected with larvae of the tumbu fly, Cordylobia anthropophaga; six with larvae of the botfly, Dermatobia hominis, and one patient presented with an infection with Hypoderma lineatum. Dermatobia hominis was exclusively acquired in the American tropics and Cordylobis anthropophaga exclusively in Africa, whereas infection with Hypoderma lineatum was acquired in Nepal. The number of larvae removed from the skin was markedly higher in patients infected with the tumbu fly (average of five larvae) compared to the botfly (average of 1.7 larvae), whereas pain was more frequently reported from patients with botfly infestation. Treatment consisted in the removal of the larvae by forceps or surgical incision in tumbu or botfly infection and oral application of ivermectin in Infection with Hypoderma lineatum. This led to complete recovery mall patients. Conclusions. In patients presenting with cutaneous lesions after return from tropical countries, myiasis has to be considered as a differential diagnosis. Simple and effective therapy is available through removal of the maggots. [ABSTRACT FROM AUTHOR]

Failures of mefloquine prophylaxis in travellers returning from Africa have been reported repeatedly. Non-compliance to chemoprophylaxis is considered to be a major factor for failure. Only few reports on mefloquine prophylaxis failure in sub-Saharan Africa were able to report blood levels of the drug that were sufficient for prophylactic effectiveness. We report the case of a 44-year-old German female who travelled to Tanzania for 3 weeks. The patient reported that she never missed a dose of mefloquine during her weekly prophylaxis schedule. Four weeks after returning from Tanzania, the patient presented with fever, headache and myalgia. Only a few trophozoites of Plasmodium falciparum were found in a thick film. Blood levels of mefloquine at that stage were at 1400 ng/ml, thus largely excluding non-compliance and malabsorption. To our knowledge, this is the first case of confirmed prophylaxis failure due to mefloquine resistance in East Africa. [Copyright &y& Elsevier]

Background: The indications for prescribing malaria chemoprophylaxis lack a solid evidence base that results in subjectivity and wide variation of practice across countries and among professionals., Methods: European experts in travel medicine, who are members of TropNetEurop, participated in a survey conducted using the Delphi method. This technique aims at evaluating and developing a consensus through iterations of questionnaires, controlled feedback, and statistical group responses., Results: A first questionnaire, including questions about controversial issues in prescribing malaria prophylaxis, required responses on a visual scale between 1 and 10. The questionnaire included issues on problematic prescribing, characteristics of drugs, relevance of geography, and importance of insect bite prevention. The repeat questionnaire with the group response from the first round revealed an increasing consensus on most issues. A second survey considered 14 practical scenarios (including two internal standards) and investigated preferred choice of prophylaxis. A significant consensus was noted in 8 of 14 scenarios, which did not increase after a second round. The analysis revealed a wide variation in prescribing choices with preferences grouped by region of practice, and a greater willingness to prescribe in northern and southern Europe than in central Europe. The second round showed a 9.5% change of opinion., Conclusions: The study shows that improving the evidence base on efficacy and tolerability and risk of malaria for prescribing chemoprophylaxis is needed as is further discussion across Europe to achieve harmonization of prescribing practice.

When using all its advantages of clinical vigilance, direct communication,and fast feedback, a clinical surveillance network can be remarkably effective in detecting sentinel events and in translating the new information into modifications of clinical practice. Travelers have great advantage when serving as surveillance tools for imported diseases. They travel widely and potentially expose themselves to all types of infectious diseases, they are very mobile, and they return during the incubation period of most diseases to a medical system that is capable of achieving fast and definitive diagnosis. Clustering of infections in returnees can be used immediately to warn outbound travelers of a particular risk and to increase their protection. In addition, travelers can also serve as "canary birds" for disease outbreaks in developing countries that might not be able to provide facilities for fast diagnosis. Information derived from returning travelers can be invaluable for the host country if channeled back to the medical authorities. TropNetEurop screening for increases in unexpected notifications has proved to be a sensitive early warning tool for the detection of increased transmission rates in endemic countries. For the future, it is hoped that traditional surveillance systems and recently introduced networks will be able to cooperate more fully. All systems have strengths and weaknesses and can gain from information provided by each other. Linkage of existing networks, which avoids duplication of work and fully exploits the information potential of all combined systems, should be targeted.

Between November 2002 and March 2003, 17 cases of malaria (1 fatal) were observed in illegal Chinese immigrants who traveled to Italy through Africa. A further cluster of 12 was reported in August, 2002. Several immigrants traveled by air, making the risk of introducing sudden acute respiratory syndrome a possibility should such illegal immigrations continue.