Population pharmacokinetics of mefloquine, administered as a fixed-dose combination of artesunate-mefloquine in Indian patients for the treatment of acute uncomplicated Plasmodium falciparum malaria.

BACKGROUND: Fixed-dose combinations of artemisinin combination therapy are strongly recommended to facilitate drug administration and compliance. New fixed-dose combinations must nevertheless be evaluated in relevant populations in terms of efficacy and pharmacokinetics. METHODS: A single-arm, open-label, clinical trial was performed in Indian patients with acute uncomplicated Plasmodium falciparum malaria to investigate the efficacy and the pharmacokinetics of mefloquine when combined with artesunate in a fixed-dose combination (400/200 mg of mefloquine base/artesunate). The pharmacokinetic analysis was performed using a population approach. RESULTS: Seventy-seven patients were included in the study. Mefloquine pharmacokinetics obeys a two-compartment model with first-order absorption and elimination. Mean parameter estimates (% inter-individual variability) were as follows: 0.16 h(-1) (75%) for the absorption rate constant, 1.13 L/h (30%) for the apparent plasma clearance, 271 L (21%) for the apparent central distribution volume, 344 L (54%) for the apparent peripheral distribution volume, and 1.43 L/h for the apparent distribution clearance. These values were consistent with the pharmacokinetic results described in Thai patients. No significant covariate was found for clearance. Body weight explained the inter-individual variability of the apparent central and peripheral distribution volumes. The PCR-adjusted efficacy of the treatment was 100%. CONCLUSIONS: The lack of significant covariate explaining the inter-individual variability of mefloquine clearance, combined with the excellent efficacy, supports the use of the standard 200/400 mg of artesunate-mefloquine fixed-dose combination in Indian patients with uncomplicated P. falciparum malaria. CLINICAL TRIAL REGISTRATION: ISRCTN70618692.

Mass administration of the antimalarial drug mefloquine to Guantánamo detainees: a critical analysis.

Recently, evidence has emerged from an unusual form of mass drug administration practised among detainees held at US Naval Station Guantánamo Bay, Cuba ('Guantánamo'), ostensibly as a public health measure. Mefloquine, an antimalarial drug originally developed by the US military, whose use is associated with a range of severe neuropsychiatric adverse effects, was administered at treatment doses to detainees immediately upon their arrival at Guantánamo, prior to laboratory testing for malaria and irrespective of symptoms of disease. In this analysis, the history of mefloquine's development is reviewed and the indications for its administration at treatment doses are discussed. The stated rationale for the use of mefloquine among Guantánamo detainees is then evaluated in the context of accepted forms of population-based malaria control. It is concluded that there was no plausible public health indication for the use of mefloquine at Guantánamo and that based on prevailing standards of care, the clinical indications for its use are decidedly unclear. This analysis suggests the troubling possibility that the use of mefloquine at Guantánamo may have been motivated in part by knowledge of the drug's adverse effects, and points to a critical need for further investigation to resolve unanswered questions regarding the drug's potentially inappropriate use.

Therapeutic efficacy and safety of dihydroartemisinin-piperaquine versus artesunate-mefloquine in uncomplicated Plasmodium falciparum malaria in India.

BACKGROUND: Resistance in Plasmodium falciparum to commonly used anti-malarial drugs, especially chloroquine, is being increasingly documented in India. By 2007, the first-line treatment for uncomplicated malaria has been revised to recommend artemisinin-based combination therapy (ACT) for all confirmed P. falciparum cases. OBJECTIVE: The objective of this study was to compare the efficacy, safety and tolerability between dihydroartemisinin-piperaquine (DP) and artesunate plus mefloquine (A + M) drug combinations in the treatment of uncomplicated P. falciparum malaria in India. METHODS: Between 2006 and 2007, 150 patients with acute uncomplicated P. falciparum malaria were enrolled, randomized to DP (101) or A + M (49) and followed up for 63 days as part of an open-label, non-inferiority, randomized, phase III multicenter trial in Asia. RESULTS: The heterogeneity analysis showed no statistically significant difference between India and the other countries involved in the phase III study, for both the PCR-corrected and uncorrected cure rates. As shown at the whole study level, both forms of ACT were highly efficacious in India. In fact, in the per protocol population, the 63-day cure rates were 100% for A + M and 98.8% for DP. The DP combination exerted a significant post-treatment prophylactic effect, and compared with A + M a significant reduction in the incidence of new infections for DP was observed (respectively 17.1% versus 7.5% of patients experienced new infection within follow up). Parasite and fever clearance was rapid in both treatment arms (median time to parasite clearance of one day for both groups). Both DP and A + M were well tolerated, with the majority of adverse events of mild or moderate severity. The frequencies of individual adverse events were generally similar between treatments, although the incidence of post treatment adverse events was slightly higher in patients who received A + M with respect to those treated with DP. CONCLUSION: DP is a new ACT displaying high efficacy and safety in the treatment of uncomplicated P. falciparum malaria and could potentially be considered for the first-line treatment of uncomplicated falciparum malaria in India. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 81306618.

[Mood disorder after malaria prophylaxis with mefloquine (two case reports)]. / Troubles de l'humeur et prophylaxie antipaludique (méfloquine) : à propos de deux cas.

INTRODUCTION: Mefloquine (Lariam) is the drug of choice as malaria prophylaxis for travel to chloroquine-resistant areas. Severe neuropsychiatric side effects are rare. We report two clinical cases of mood disorders: mania and a major depressive episode with psychotic characteristics in two patients with mefloquine antimalarial prophylaxis. FIRST CLINICAL CASE: A 31-year-old man had taken mefloquine at a rate of 250mg/week as malaria prophylaxis for his mission in Democratic Republic of Congo. He developed mania with psychotic symptoms after taking five tablets of 250mg of mefloquine. He exhibited an elevated mood and also developed delusions of grandeur, reference and persecution, with auditory hallucinations. The physical examination and the blood laboratory tests were normal. The patient was treated with an atypical neuroleptic (olanzapine 20mg/d) leading to a complete resolution of symptomatology at the end of 3 weeks. SECOND CLINICAL CASE: A 27-year-old man presented a major depressive episode with psychotic symptoms after 1 week on his return from a stay in Democratic Republic of Congo, where he had taken mefloquine during 6 months as malaria prophylaxis (250mg/week). His physical examination and investigations (full blood test, serology and MRN) were normal. The patient was treated with clomipramine (150mg/d) and olanzapine (20mg/d). The outcome was favorable after 4 weeks. DISCUSSION: Mefloquine is widely accepted as a safe and effective treatment and a prophylactic agent for chlorquine-resistant malaria. Common neuropsychiatric adverse effects of mefloquine can occur in up to 40% of patients, such as dizziness, sleep disturbances, anorexia, ataxia, and fatigue. Other more serious adverse reactions are rare. They are represented primarily by panic attacks, convulsions, acute psychosis, paranoid delusions, suicidal ideation, disorders of mood: major depressive episode and the manic excitation. The incidence of such neuropsychiatric effects is 1/10,000 to 1/15,000 during the prophylactic treatment. The causal mechanism for the side effects is not known. Several risk factors increasing the neurotoxicity of mefloquine can be identified, the patient with personal or family history of psychiatric disorders are more frequently concerned. Alcohol and the association with other drugs (like quinine) are two other risk factors. CONCLUSION: It is relevant for medical practitioners to be aware of the severe neuropsychiatric side effects of mefloquine as malaria prophylaxis. It requires investigation of the risk factors such as personal or family history of psychiatric disorders.

Cost-effectiveness analysis of malaria chemoprophylaxis for travellers to West-Africa.

BACKGROUND: The importation of malaria to non-endemic countries remains a major cause of travel-related morbidity and a leading cause of travel-related hospitalizations. Currently they are three priority medications for malaria prophylaxis to West Africa: mefloquine, atovaquone/proguanil and doxycycline. We investigate the cost effectiveness of a partial reimbursement of the cheapest effective malaria chemoprophylaxis (mefloquine) for travellers to high risk areas of malaria transmission compared with the current situation of no reimbursement. METHODS: This study is a cost-effectiveness analysis based on malaria cases imported from West Africa to Switzerland from the perspective of the Swiss health system. We used a decision tree model and made a literature research on the components of travel related malaria. The main outcome measure was the cost effectiveness of malaria chemoprophylaxis reimbursement based on malaria and deaths averted. RESULTS: Using a program where travellers would be reimbursed for 80% of the cost of the cheapest malaria chemoprophylaxis is dominant (i.e. cost saving and more effective than the current situation) using the assumption that currently 68.7% of travellers to West Africa use malaria chemoprophylaxis. If the current usage of malaria chemoprophylaxis would be higher, 82.4%, the incremental cost per malaria case averted is € 2'302. The incremental cost of malaria death averted is € 191'833.The most important factors influencing the model were: the proportion of travellers using malaria chemoprophylaxis, the probability of contracting malaria without malaria chemoprophylaxis, the cost of the mefloquine regimen, the decrease in the number of travellers without malaria chemoprophylaxis in the reimbursement strategy. CONCLUSIONS: This study suggests that a reimbursement of 80% of the cost of the cheapest effective malaria chemoprophylaxis (mefloquine) for travellers from Switzerland to West Africa is highly effective in terms of malaria cases averted and is cost effective to the Swiss health system. These data are relevant to discussions about the cost effectiveness of malaria chemoprophylaxis reimbursement for vulnerable groups such as those visiting friends and relatives who have the highest risk of malaria, who are least likely to use chemoprophylaxis.

Efficacy and effectiveness of dihydroartemisinin-piperaquine versus artesunate-mefloquine in falciparum malaria: an open-label randomised comparison.

BACKGROUND: Artemisinin-based combinations are judged the best treatments for multidrug-resistant Plasmodium falciparum malaria. Artesunate-mefloquine is widely recommended in southeast Asia, but its high cost and tolerability profile remain obstacles to widespread deployment. To assess whether dihydroartemisinin-piperaquine is a suitable alternative to artesunate-mefloquine, we compared the safety, tolerability, efficacy, and effectiveness of the two regimens for the treatment of uncomplicated falciparum in western Myanmar (Burma). METHODS: We did an open randomised comparison of 3-day regimens of artesunate-mefloquine (12/25 mg/kg) versus dihydroartemisinin-piperaquine (6.3/50 mg/kg) for the treatment of children aged 1 year or older and in adults with uncomplicated falciparum malaria in Rakhine State, western Myanmar. Within each group, patients were randomly assigned supervised or non-supervised treatment. The primary endpoint was the PCR-confirmed parasitological failure rate by day 42. Failure rates at day 42 were estimated by Kaplan-Meier survival analysis. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN27914471. FINDINGS: Of 652 patients enrolled, 327 were assigned dihydroartemisinin-piperaquine (156 supervised and 171 not supervised), and 325 artesunate-mefloquine (162 and 163, respectively). 16 patients were lost to follow-up, and one patient died 22 days after receiving dihydroartemisinin-piperaquine. Recrudescent parasitaemias were confirmed in only two patients; the day 42 failure rate was 0.6% (95% CI 0.2-2.5) for dihydroartemisinin-piperaquine and 0 (0-1.2) for artesunate-mefloquine. Whole-blood piperaquine concentrations at day 7 were similar for patients with observed and non-observed dihydroartemisinin-piperaquine treatment. Gametocytaemia developed more frequently in patients who had received dihydroartemisinin-piperaquine than in those on artesunate-mefloquine: day 7, 18 (10%) of 188 versus five (2%) of 218; relative risk 4.2 (1.6-11.0) p=0.011. INTERPRETATION: Dihydroartemisinin-piperaquine is a highly efficacious and inexpensive treatment of multidrug-resistant falciparum malaria and is well tolerated by all age groups. The effectiveness of the unsupervised treatment, as in the usual context of use, equalled its supervised efficacy, indicating good adherence without supervision. Dihydroartemisinin-piperaquine is a good alternative to artesunate-mefloquine.

Relapsing vivax malaria after 6 months of daily atovaquone/proguanil in Afghanistan: the case for expanded use of primaquine as a causal prophylactic.

A 22-year-old soldier presented with vivax malaria after extended travel in Afghanistan. Compliant with atovaquone/proguanil in country, he discontinued prophylaxis immediately upon departure. This case raises important issues regarding prophylactic choice and compliance during travel to Plasmodium vivax endemic locations and primaquine's registration status for prophylaxis and use by practitioners.

Psychosis with paranoid delusions after a therapeutic dose of mefloquine: a case report.

BACKGROUND: Convenient once-a-week dosing has made mefloquine a popular choice as malaria prophylaxis for travel to countries with chloroquine-resistant malaria. However, the increased use of mefloquine over the past decade has resulted in reports of rare, but severe, neuropsychiatric adverse reactions, such as anxiety, depression, hallucinations and psychosis. A direct causality between mefloquine and severe reactions among travelers has been partly confounded by factors associated with foreign travel and, in the case of therapeutic doses of mefloquine, the central nervous system manifestations of Plasmodium infection itself. The present case provides a unique natural history of mefloquine-induced neuropsychiatric toxicity and revisits its dose-dependent nature. CASE PRESENTATION: This report describes an acute exacerbation of neuropsychiatric symptoms after an unwarranted therapeutic dose (1250 mg) of mefloquine in a 37-year-old male previously on a once-a-week prophylactic regimen. Neuropsychiatric symptoms began as dizziness and insomnia of several days duration, which was followed by one week of escalating anxiety and subtle alterations in behaviour. The patient's anxiety culminated into a panic episode with profound sympathetic activation. One week later, he was hospitalized after developing frank psychosis with psychomotor agitation and paranoid delusions. His psychosis remitted with low-dose quetiapine. CONCLUSION: This report suggests that an overt mefloquine-induced psychosis can be preceded by a prodromal phase of moderate symptoms such as dizziness, insomnia, and generalized anxiety. It is important that physicians advise patients taking mefloquine prophylaxis and their relatives to recognize such symptoms, especially when they are accompanied by abrupt, but subtle, changes in behaviour. Patients with a history of psychiatric illness, however minor, may be at increased risk for a mefloquine-induced neuropsychiatric toxicity. Physicians must explicitly caution patients not to self-medicate with a therapeutic course of mefloquine when a malaria diagnosis has not been confirmed.

Mefloquine-induced pneumonitis.

Mefloquine is indicated as oral treatment and as prophylaxis for malaria in areas where chloroquine-resistant malaria is present. Gastrointestinal and neuropsychiatric side effects of mefloquine are well known. More severe neuropsychiatric disorders such as psychosis, depression, hallucinations, and seizures are also reported in the literature. We are reporting a case of drug-induced pneumonia due to mefloquine. This diagnosis was confirmed 4 months after the adverse event, after restarting the same malaria prophylaxis, which could be considered as an unintentional provocation test. This is the third case report in the literature of acute lung injury caused by mefloquine.

An open randomized clinical trial of Artekin vs artesunate-mefloquine in the treatment of acute uncomplicated falciparum malaria.

Malaria remains a major cause of morbidity and mortality in tropical countries and subtropical regions in the world. Southeast Asia has the most resistant malaria parasites in the world, which has limited treatment options in this region. In response to this situation, short-course artemisinin-based combination therapies (ACTs) have been developed. The combination of dihydroartemisinin (DHA) and piperaquine (PQP) in the form of Artekin has been developed as an alternative to established combinations, such as artesunate-mefloquine, primarily to reduce treatment costs and toxicity. We conducted a study comparing a standard treatment for acute uncomplicated falciparum malaria (artesunate 4 mg/kg/day together with mefloquine 8 mg/kg/day oral route once a day for 3 days) (Group A) and a combination of dihydroartemisinin 40 mg and piperaquine 320 mg in the form of Artekin given once a day for 3 days (Group B) to determine safety, efficacy, and tolerability. One hundred and eighty patients were randomly enrolled at the ratio of 1:2 into groups A:B. All patients had rapid initial clinical and parasitological responses. There were no significant differences in fever clearance time or parasite clearance time between both groups. The 28-day cure rates were high, at 100% and 99%, in groups A and B, respectively. We conclude that Artekin was as effective and well-tolerated as artesunate-mefloquine, and can be used alternatively as the current treatment for multidrug-resistant P. falciparum malaria.

An open, randomized trial of three-day treatment with artesunate combined with a standard dose of mefloquine divided over either two or three days, for acute, uncomplicated falciparum malaria.

The combination of artesunate and mefloquine is currently one of the most effective treatments for multidrug-resistant Plasmodium falciparum malaria. Simultaneous, rather than sequential treatment with the two drugs, would allow better patient compliance. We therefore evaluated three-day treatment with artesunate combined with either 2 or 3 days of mefloquine co-administered once a day with artesunate. The study was an open, randomized trial for acute, uncomplicated falciparum malaria and was conducted at the Bangkok Hospital for Tropical Diseases. One hundred and twenty adult patients were randomized to two treatment groups. Group 1 patients received 4 mg/kg/day of artesunate for 3 days and 3 daily doses of 8.0 mg/kg/day mefloquine given with artesunate. Group 2 patients received the same dose of artesunate and the same total dose of mefloquine (25 mg/kg). However, the mefloquine was given as 15 mg/kg on the first day and 10 mg/kg/ on the second day, again with artesunate. The baseline demographic and clinical characteristics of the patients in the two groups were similar. The cure rates for the 3-day and 2-day mefloquine regimens were 100% and 99%, respectively. There were no significant differences in either median fever clearance times (group 1=32 hours; group 2=33 hours) or mean parasite clearance times (group 1=42.3 hours; group 2=43.3 hours). Both regimens were well tolerated and there were no significant differences in the incidence of adverse effects. Nausea or vomiting occurred in 3.8% of patients in both groups and transient dizziness occurred in 4% of group 1 and 9% of group 2 patients. These results suggest that a 3-day regimen of mefloquine administered with artesunate is effective and well tolerated. This practical regimen could improve patient compliance.

Life-saving rectal artesunate for complicated malaria in children.

We report the effectiveness of two regimens of rectal artesunate formulation in treating 13 Thai children with cerebral/complicated falciparum malaria. The drug was given at an initial dose of 40 mg/kg bodyweight, in 3 or 4 divided doses in the first 24 hours, followed by 10 mg/kg bodyweight once daily for three consecutive days. Mefloquine, at a dose of 15 mg/kg bodyweight was given orally at 72 hours after the initial dose of artesunate, followed by 10 mg/kg bodyweight 6 hours later. Three cases with cerebral malaria gained consciousness within 20 hours of artesunate administration. The median time required for reduction of parasitemia by 90% of the initial value (P90) in 13 children was 11.2 hours. No recrudescence was observed in any of the patients during the 28-day follow-up period. Plasma concentrations of artesunate and dihydroartemisinin (active plasma metabolite of artesunate) measured in two patients who received the high initial dose regimen (20 mg/ kg bodyweight) suggested rapid absorption and adequate plasma concentrations of both compounds following the administration of artesunate via the rectal route. Further studies for the optimized regimen of rectal artesunate in the treatment of cerebral/complicated childhood falciparum malaria in areas of multidrug resistance are warranted.

Comparison of whole blood and serum levels of mefloquine and its carboxylic acid metabolite.

Because of the widespread presence of chloroquine-resistant Plasmodium falciparum malaria, mefloquine is now the recommended drug of choice for long-term malaria prophylaxis in these areas. Although several studies have compared plasma and whole blood concentrations of either mefloquine or its carboxylic acid metabolite, we report the first comparison of serum and whole blood levels in 86 Dutch marines taking 250 mg of mefloquine weekly for 18 weeks while deployed in western Cambodia. All samples were taken during steady-state and at 42-48 hr after the most recent dose. The concentration of mefloquine in serum (mean = 979 ng/ml) was significantly greater than in whole blood (mean = 788 ng/ml) (P < 0.00001, by paired t-test) with an overall mean ratio of 1.28. The concentration of the metabolite in serum (mean = 3,039 ng/ml) was also significantly greater than in whole blood (mean = 1,390 ng/ml) (P < 0.00001, by paired t-test) with an overall mean ratio of 2.25. These findings are similar to previous reports of plasma-to-whole blood levels. Furthermore, we report that the within-individual ratios of the metabolite concentration to the mefloquine concentration were also found to be significantly different in serum (3.79; P < 0.00001, by paired t-test) and in whole blood (2.02; P < 0.00001, by paired t-test). Appropriate attention must be given to these differences when comparing serum and whole blood concentrations of either mefloquine or its metabolite to avoid misinterpretation of their respective levels. Also, the determination of the relative mefloquine ratios in various blood fluids, as well as the documentation of the metabolite levels and their ratios, is critical to the appropriate interpretation of both chemoprophylaxis and chemotherapy, especially in the presence of resistant strains.

Steady state pharmacokinetics of mefloquine in long-term travellers.

Mefloquine is an antimalarial drug with a 3-week elimination half-life, which has led to concerns that toxic accumulation may occur during weekly administration for long-term malaria chemoprophylaxis. Despite the endorsement of weekly mefloquine by the World Health Organization and the United States Centers for Disease Control, mefloquine pharmacokinetics have been incompletely studied in subjects taking the drug once weekly for more than 4 weeks. Our objective was to study plasma mefloquine concentrations in travelers taking mefloquine 250 mg once weekly for 3 months. Multiple mefloquine concentrations were measured by high pressure liquid chromatography following the 1st, 2nd and 10th to 13th of 13 weekly doses of 250 mg mefloquine taken by 15 Canadian travellers (median age 23 years; 6 male, 14 white). Steady state was achieved in all subjects by or before the 10th dose. Mefloquine pharmacokinetic values were comparable to those previously reported by other investigators. In 7 subjects, 2 peaks of mefloquine and metabolite concentration followed ingestion, suggesting redistribution of mefloquine. Mefloquine concentration 14 d after the last dose was 74% of the level 7 d after the last dose. In conclusion, pharmacokinetic values determined by this study support mefloquine weekly dosing for long-term malaria chemoprophylaxis; toxic accumulation does not occur and weekly dosing is associated with significantly higher trough levels than 14 d dosing.

Pharmacokinetics of prophylactic mefloquine in Thai healthy volunteers.

Malaria constitutes one of the most serious public health problems in Thailand. The disease undermines the health of the people and threatens the economy and security of the country as it is most prevalent in the rural region in forested mountain areas along the border where government officials (border police) have to perform their duties. A safe and effective prophylactic drug for use by these government officials is needed. Nine healthy border police volunteers who were working on the Thai-Cambodia border, aged between 22 to 50 years, and whose weight ranged between 48 and 61 kg, with no history of liver or kidney disease were recruited into the study. 375 mg of mefloquine (as Fansimef tablets) was given as a loading dose, followed by 250 mg every 4 weeks for 4 doses. Whole blood concentrations of mefloquine were measured by high performance liquid chromatography at intervals for 19 weeks. None of the volunteers developed malaria during study period. Seven volunteers had mild adverse effects which required no specific treatment. No changes in liver or renal function or in blood profiles occurred during 19 weeks of observation. Pharmacokinetic analysis revealed a mean maximum concentration of 420 +/- 141 ng/ml a time to peak concentration of 12 +/- 8 hours, terminal half-life was 14.93 +/- 4.43 days, apparent volume of distribution (Vd/f) was 16.5 +/- 5.6 l/kg and total clearance was 0.99 +/- 0.62 ml/min/kg. The mean minimum whole blood mefloquine concentration derived from this study was approximately 100 ng/ml which is considered to be low for treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

[Neuropsychiatric symptoms in preventive antimalarial treatment with mefloquine: apropos of 2 cases]. / Manifestations neuropsychiatriques sous prophylaxie antipaludique par méfloquine: à propos de deux observations.

Two observations of severe neuropsychiatric reactions occurring during chemoprophylaxis with mefloquine are reported. The first case regards a 43 years old woman who developed a severe depression with visual and auditive hallucinations and a paranoid delusion. She was treated by clomipramine and risperidone. The second case concerns a 55 years old man who developed an acute psychosis with confusion. He was treated with halopridol during a short time. He presented twice an acute psychosis during a chemoprophylaxis with mefloquine. Several cases of neuropsychiatric side effects with mefloquine chemoprophylaxis or treatment have been described. Authors estimate that one of 250 therapeutic users has severe neuropsychiatric reactions, compared with one of 10,000 to 15,000 in the prophylaxis users. Disorders could last from 15 minutes to several weeks. Women and patients with personal or familial antecedents of psychiatric disorders are more frequently concerned. Alcohol and the association with other antimalarial drugs (like quinine) are two other risk factors. Therefore, some advices may be suggested regarding the use of mefloquine for malaria prophylaxis and treatment.

[Considering disparities in resistance of Plasmodium falciparum in Africa in chemoprevention decisions]. / Prise en compte des disparités de résistance de Plasmodium falciparum en Afrique dans la décision chimioprophylactique.

OBJECTIVES: Assess the efficacy of preventive and curative treatments of imported malaria. METHODS: The in vitro drug susceptibility of mefloquine, chloroquine and cycloguanil was determined against African isolates of Plasmodium falciparum from imported malaria cases by an isotopic in vitro test or a genomic approach. RESULTS: Plasmodium falciparum resistance to mefloquine, chloroquine or to the dihydrofolate reductase inhibitor was present in 5.2%, 46% and 42% of isolates respectively. Plasmodium falciparum drug resistance to chloroquine or antifolinics was more frequent in permanent than in seasonal malarial transmission areas. Simultaneous resistance to chloroquine and antifolinics was observed in 17% of isolates between 1991 and 1994 and in 28% between 1995 and 1997.

[Malaria of native Africans after returning home from European residence]. / Afrikában felnótt egyének--hosszabb európai tartózkodást követóen--hazautazáskor fellépó maláriája.

According to the authors experiences African indigenous people can fall ill with malaria the same manner as the non-immune Europeans returning home after European residence. If the Africans live for many years in temperate country, their semi-immune status against malaria have gained in childhood dies away because of the mosquito bites do not happen in Europe. Therefore Africans who have lived for many years in temperate zone, need the same chemoprofilaxis and measures against malaria as the Europeans do if they return home. If these Africans fall ill with malaria, the illness can appear in severe form and they need firm antimalaria treatment even in an intensive care unit.