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D Stürchler

Publications and source records attributed to D Stürchler.

At least 19 recordsLinked to original sources
PubMed2001

[Malaria--chemoprophylaxis 2001].

An estimated 20,000 to 30,000 cases of imported malaria are annually diagnosed in industrialised countries. Some 700 of them concern Swiss travellers and foreign guests. Exposure prophylaxis and chemoprophylaxis for high risk destinations lower the risk of malarial disease. The latter is defined as regular intake of antimalarial drugs in subtherapeutic dosage in order to suppress the development of clinical disease. Drugs are usually taken from one week before travel until four weeks after return from an endemic area. Mefloquine, doxycycline, chloroquine plus proguanil, and presumably soon also atovaquone plus proguanil are available in Switzerland for chemoprophylaxis.

Africa↗
PubMed2000

A waterborne outbreak of small round structured virus, campylobacter and shigella co-infections in La Neuveville, Switzerland, 1998.

An outbreak of gastro-enteritis occurred in La Neuveville, township with 3358 inhabitants. A retrospective cohort study of 1915 participants showed that 1607 (84%) had been ill. Campylobacter jejuni was isolated from 28 patient faecal samples, Shigella sonnei from 21 patients and small round structured viruses (SRSV) from 6 patients. More than one pathogen was identified in eight persons. The epidemic curve was characteristic of a point-source outbreak. The risk for illness was significantly higher among persons who had drank unboiled drinking water than among those who had not (1290 [80.3%] of 1607 vs. 86 [27.9%] of 308; RR = 2.87; 95% CI 2.40-3.45). Risk increased significantly with the quantity of water consumed (P < 0.00 x 10(-6)). An SRSV isolate from water and one human faeces had an identical DNA sequence. The outbreak was due to a pump failure producing a spill of sewage into the groundwater. We conclude that transmission was waterborne and that measures including early warning, basic hygiene and sanitation improvements controlled this epidemic.

Adolescent↗
PubMed1999

Human phase I vaccine trials of 3 recombinant asexual stage malaria antigens with Montanide ISA720 adjuvant.

Two phase I vaccine trials were conducted to test the immunogenicity and safety of a vaccine containing three recombinant malaria antigens from the asexual stage of Plasmodium falciparum. The three antigens are a fragment of MSP1 (190LCS.T3); MSP2 and a portion of RESA and were formulated in Montanide ISA720 adjuvant. These trials investigated the dose response of each antigen for eliciting both antibody and T-cell responses and the immunogenicity of a mixture of the antigens compared with the antigens injected separately. All three antigens elicited both antibody and T-cell responses. Strong T-cell responses were observed with 190LCS.T3 and RESA with stimulation indices exceeding 100 for peripheral blood leucocytes in some individuals. The antibody responses were generally weak. The human antibody responses observed with MSP2 in Montanide ISA720 were not significantly different from those obtained in an earlier trial which used MSP2 with alum as the adjuvant. No antigenic competition was observed: volunteers receiving a mixture of antigens had similar responses to those receiving the three antigens at separate sites. Tenderness and pain at the injection site were common over the first few days following immunization. In some volunteers, especially those receiving the highest doses tested, there was a delayed reaction at the injection site with pain and swelling occurring approximately 10 days after injection.

Adjuvants, Immunologic↗
PubMed1997

Tolerability and Effectiveness of Malaria Chemoprophylaxis with Mefloquine or Chloroquine with or without Co-medication.

Background: To determine the relevance of drug interactions with co-medication for effectiveness and tolerability of antimalarial chemoprophylaxis. Method: A database (MALPRO2) on travelers on their flight home from Africa to Europe between July 1988 and December 1991 was reanalyzed. It contains data on prophylaxis with mefloquine (n = 48,264), with chloroquine (6,752), with chloroquine plus proguanil (19,727), and with no prophylaxis (3,871). The comparison of rates of malaria incidence and adverse events (AEs) between users and nonusers of co-medication was expressed by relative risk (RR). Results: Fifty-three percent of travelers (63% of females, 43% of males) used co-medication in all prophylaxis groups, with an average of 1.35 additional drugs per person and about two AEs reported per person. With the exception of antidiarrheals plus mefloquine, malaria incidence with co-medication was lower (RR = 0.8) than without co-medication. In all regimens, the proportion of travelers reporting AEs was about 1.5-fold with co-medication (p<.01); that reporting severe AEs was twice as high as compared to with no co-medication. Mefloquine AE rates for various classes of co-medication were similar to that of chloroquine, with highest AE and severity rates with neuropsychiatric drugs (excluding antiepileptics, RR = 1.9 and 2.9), and lowest rates with cardiovasculars (RR = 1.1 and 1.0). Various co-medications were used with different frequencies in males and females, and the latter reported more AEs. Conclusion: These data suggest that co-medications commonly used by travelers have no significant clinical impact on safety and effectiveness of prophylaxis with mefloquine or chloroquine. Increased frequency and severity of AEs when using co-medication rather is explained by underlying illness.

Journal Article↗
PubMed1997

[Experiences with the Swiss mandatory disease notification].

Advantages and setbacks of the existing Swiss disease notification system are reviewed. The public takes interest in the notification data output. The voluntary sentinels provide useful early warning. Currently, 60 conditions are notifiable. It is intended to lower this number to < 30. Other measures to upgrade the system include annual review and publication of an updated list of notifiable diseases, limitation to an essential core of parameters collected from physicians on initial and follow-up questionnaires, and practical advice on diagnostic and control measures provided for in questionnaires for the infectious disease under query.

Disease Notification↗
PubMed1996

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.

Journal Article↗
PubMed1996

Mefloquine tolerability during chemoprophylaxis: focus on adverse event assessments, stereochemistry and compliance.

This longitudinal study of travellers to Africa taking mefloquine (MQ) chemoprophylaxis aimed to quantify and assess non-serious adverse events (AE) occurring during short-term prophylaxis and relate these to concentrations of racemic MQ, its enantiomers and metabolite. A total of 420 volunteers (52% F) participated. AEs with some impact on activities were reported by 11.2% of participants including 7.9% of neurological/psychiatric symptoms. Women were more likely to report AEs (P = 0.02). The standardized questionnaires used showed more pathological indicators in travellers who reported subjective AE with significantly more dizziness, distress, sleep disturbances and a high total mood disturbance (TMD) in the AE group. There was, however, no significant performance deficit in computerized psychomotor tests in those experiencing AE. Furthermore, no significant differences were observed in enantiomer ratios, metabolite concentrations, or racemic MQ levels in participants with or without AEs suggesting that these factors are not the main predictors of mefloquine intolerability.

Adolescent↗
PubMed1995

The chemotherapy of rodent malaria. LII. Response of Plasmodium yoelii ssp. NS to mefloquine and its enantiomers.

A comparison was made between the blood schizontocidal action in mice of racemic mefloquine hydrochloride and the free bases of its (+)- and (-)-enantiomers (Ro 13-7224 and Ro 13-7225) against chloroquine-resistant Plasmodium yoelii ssp. NS. The racemic hydrochloride was two to three times as active against this parasite in mice as either of the enantiomer free bases, which were of similar activity to each other. Under drug selection pressure, the parasites acquired resistance in approximately the same time for each of the three compounds.

Animals↗
PubMed1995

The antimalarial drug, Ro 42-1611 (arteflene), does not affect cytoadherence and cytokine-inducing properties of Plasmodium falciparum malaria parasites.

The purpose of this study was to investigate the ability of the antimalarial drug, Ro 42-1611 to block parasite mediated cytokine induction in vitro as well as cytoadherence of infected erythrocytes to melanoma cells in vitro. The biological activity of Ro 42-1611 was confirmed as it blocked Plasmodium falciparum growth in cultures. Ro 42-1611, had no major effect on TNF, IL-alpha or IL-6 cytokine release from mononuclear cells stimulated with malaria antigens or lipopolysaccharide and it did not affect cell viability. Ro 42-1611 only slightly suppressed cytoadherence of infected erythrocytes to melanoma cells. The therapeutic effect of To 42-1611 appears to be confined to its parasite killing activity.

Adult↗
PubMed1995

[NANP]19-5.1. A malaria vaccine field trial in Nigerian children.

[NANP]19-5.1 is a recombinant Plasmodium falciparum vaccine consisting of 19 repeats of the sporozoite surface protein [NANP] and the schizont export antigen 5.1. In a previous study, an experimentally infected subject (with a history of malaria exposure and an elevated pre-immunization lymphocyte stimulation index to antigen 5.1) showed parasitaemia but no signs of clinical malaria. In an attempt to find a comparable partially immune population, we tested the vaccine in 194 schoolchildren (6 to 12 years, vaccine and placebo groups of equal size), who already possessed a certain degree of immunity. It was hoped that this immunity would be boosted by the vaccine. During the 12 weeks of observation, no child developed clinical malaria. Analysis of serum taken before and after immunization revealed that, except for eight children, all had considerable levels of antibodies to both antigens. We conclude that the trial should be repeated in younger children who are still vulnerable to clinical malaria.

Animals↗
PubMed1994

Ro 42-1611 in the treatment of patients with mild malaria: a clinical trial in Nigeria and Burkina Faso.

An open, non-comparative clinical trial was carried out in Nigeria and Burkina Faso to investigate the safety and efficacy of the novel antimalarial arteflene in patients with mild malaria. Patients were males aged 12 to 16 years, with a Plasmodium falciparum count of 10(4) to 10(5) parasites/microliters and a body temperature of 37.5 to 38.5 degrees C. Twenty-three patients received a single dose of Ro 42-1611 (arteflene), corresponding to 25 +/- 2.5 mg/kg bodyweight. Nineteen patients were evaluable for standard efficacy. Efficacy was assessed at 6, 9, 12, 24, 36, 48 and 72 hours, and at seven days, by: reduction in parasitaemia and time to parasite clearance; resolution of fever; and clinical cure (defined as the absence of signs and symptoms of malaria). Adverse events were reported at each assessment point, and laboratory tests were carried out at baseline and at 2 and 7 days. The parasite count was reduced by 50% or more in 89.5% of patients after 48 hours, and 52.6% were completely free of parasites at the same time. Normal temperature was achieved in 89.5% of patients and clinical cure in 75%, after 48 hours. One patient reported mild vertigo and mild pruritus. The lower than expected effect was thought to be due to inadequate storage of the arteflene suspension. There were no withdrawals due to adverse events and no deaths. A single dose of 25 mg/kg arteflene was found to be an effective and well-tolerated treatment for mild P. falciparum malaria.

Adolescent↗
PubMed1994

Efficacy of Ro 42-1611 (arteflene) in the treatment of patients with mild malaria: a clinical trial in Cameroon.

The novel antimalarial Ro 42-1611 (arteflene) was evaluated for safety and efficacy in an open, non-comparative study of patients with mild malaria in the south of Cameroon. Thirty male patients aged 12 to 42 years, with an initial Plasmodium falciparum count of > 5000 (mean: 21,406) parasites/microliters and a body temperature of 37.7% to 39.8 degrees C, were selected to receive a single dose of arteflene, corresponding to 25 +/- 2.5 mg/kg bodyweight. Efficacy was assessed at 6, 9, 12, 24, 36, 48 and 72 hours, and at seven days by: reduction in parasitaemia and time to parasite clearance; resolution of fever and clinical cure (defined as the absence of signs and symptoms of malaria). Adverse events were reported at baseline and at each assessment point, and laboratory tests were carried out at 2 and 7 days. The mean number of parasites/microliter fell from 21,406 at baseline to 157 after 48 hours, at which point 80% of patients were completely free of parasites. Mean body temperature was reduced from 38.9 degrees C at baseline to 37.3 degrees C 12 hours after arteflene administration, and by this time 80% of patients had a normal temperature. Clinical cure rates were also high, with 70% of patients free of all signs and symptoms after 24 hours. However, by day 7, 6/30 (20%) presented with smears positive for P. falciparum. There were no adverse events considered to be related to treatment. A single dose of 25 mg/kg arteflene was found to be an effective and well-tolerated treatment for mild P. falciparum malaria.

Adolescent↗
PubMed1993

[Emergency treatment of malaria during travel].

Stand-by therapy is the first treatment of a presumptive malaria by the traveller. Goals and possible indications are listed and the mode of application described. Information of the traveller by the physician is time consuming but very important for the correct use of stand-by therapy. The central message is the instruction to visit a doctor within 12 to 25 hours after intake of stand-by therapy, to avoid the risk of missing other diseases with similar symptoms. Fansimef and Lariam, recommended in Switzerland for stand-by therapy of malaria, are shortly reviewed.

Antimalarials↗
PubMed1993

Mefloquine compared with other malaria chemoprophylactic regimens in tourists visiting east Africa.

There is much confusion over which malaria chemoprophylaxis should be used in areas such as East Africa. We did two consecutive studies between 1985 and 1991 to assess the efficacy and side-effects of malaria chemoprophylaxis in short-term travellers to East Africa. All passengers returning from Kenya to Europe received an in-flight questionnaire and a second one three months later. Any report of documented malaria or of admission to hospital for possible side-effects was verified with the physician. 145 003 travellers completed questionnaires. Among the 139 164 who stayed in East Africa for less than one year, 296 cases of confirmed malaria were reported (275 due to P falciparum). In people who used no chemoprophylaxis, the incidence of falciparum malaria was 1.2% per month. Prophylactic effectiveness was 91% (95% Cl 85 to 94) for mefloquine, 82% (71 to 89) for pyrimethamine and sulfadoxine, 72% (56 to 82) for chloroquine plus proguanil, and 10 to 42% for chloroquine at various doses. Rates of side-effects, which were usually mild, were 18.8% for mefloquine users, 17.1% and 18.6% for chloroquine 300 mg and 600 mg base per week, respectively, 30.1% for chloroquine plus proguanil, and 11.7% for sulfadoxine and pyrimethamine. Mefloquine is significantly more effective than chloroquine plus proguanil for malaria prophylaxis in short-term tourists visiting East Africa and has a tolerance similar to that of chloroquine used alone.

Adult↗
PubMed1993

Efficacy and toxicity of fleroxacin in the treatment of travelers' diarrhea.

The efficacy and safety of fleroxacin in brief self-treatment of travelers' diarrhea were studied. In The Gambia, 195 tourists with acute diarrhea were randomized in a double-blind, controlled trial into three treatment groups: fleroxacin 400 mg for 1 day, fleroxacin 400 mg daily for 2 days, and placebo. Microbiology of stools was assessed only at recruitment. In the fleroxacin-treated groups, stool consistency was normal in 67% and 71% of the volunteers after 48 hours, as compared to 37% in the placebo group (p < 0.01). The time to total relief of diarrhea and of all symptoms was also significantly shorter in fleroxacin-treated patients. Adverse events, particularly slight neuropsychiatric reactions (headache, insomnia) were more frequent in the fleroxacin-treated groups (p < 0.05). There was no statistically significant difference in efficacy and tolerance if fleroxacin was administered for 1 or 2 days. A single dose of fleroxacin 400 mg may be recommended for the self-treatment of travelers' diarrhea.

Adolescent↗
PubMed1993

Treatment of travellers' diarrhoea with fleroxacin: a case study.

A double-blind, randomized, placebo-controlled trial was conducted to evaluate the efficacy and safety of fleroxacin for one or two days as treatment for patients with travellers' diarrhoea. A total of 195 patients who were suffering with acute diarrhoea of less than six days' duration were enrolled. One hundred and fifty-one patients, of whom 49 received placebo, 54 received fleroxacin 400 mg for one day and 48 received fleroxacin 400 mg for two days, were included in the analysis of efficacy. The results showed that fleroxacin was significantly superior to placebo, but that there was no significant difference in terms of efficacy between the one- and two-day regimens. Adverse events, particularly minor neuropsychiatric disturbances such as headache and insomnia, were significantly more common amongst patients receiving active treatment. In conclusion, a single dose of fleroxacin 400 mg could be recommended as self-treatment for visitors to high-risk countries who develop travellers' diarrhoea.

Adult↗