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.

Malaria chemotherapy trial at a minimal effective dose of mefloquine/sulfadoxine/pyrimethamine compared with equivalent doses of sulfadoxine/pyrimethamine or mefloquine alone.

In murine malaria the addition of mefloquine to sulfadoxine/pyrimethamine has been shown to exert an additive effect and to significantly slow the emergence of resistance to the individual components. In a pilot study carried out in Gabon, a reduced dosage of the triple combination with a mean of 1 mg/kg of mefloquine/2 mg/kg of sulfadoxine/0.1 mg/kg of pyrimethamine (Fansimef; Roche, Basel, Switzerland) had previously been shown to achieve high cure rates in Plasmodium falciparum malaria. To evaluate the additive effect, a randomized, double-blind trial in school children with mild P. falciparum malaria was performed in Gabon. Two hundred thirty-one patients evaluated received a single dose of either the triple combination with a mean of 1.07 mg/kg of mefloquine/2.14 mg/kg of sulfadoxine/0.11 mg/kg of pyrimethamine (group MSP), or 1.07 mg/kg of mefloquine alone (group M), or 2.14 mg/kg of sulfadoxine/0.11 mg/kg of pyrimethamine alone (group SP). In the MSP group and the SP group, 67% and 69% of the patients were parasitologically cured, respectively, compared with only 13% in the M group (P < 0.001). A significantly higher parasitemia was found in the M group compared with the MSP group or the SP group on days 2 and 3 after the start of treatment. The high efficacy of the low dose sulfadoxine/pyrimethamine regimen was the most surprising finding of this study.

Arteflene compared with mefloquine for treating Plasmodium falciparum malaria in children.

Arteflene is a synthetic peroxide recently developed from an indication of antimalarial activity found in the Chinese plant Artabotrys uncinatus. The new antimalarial was compared against mefloquine in a phase 3, open-labeled, randomized trial in children with uncomplicated Plasmodium falciparum malaria in Gabon. Patients received single oral doses of either 25 mg/kg of arteflene suspension or 15 mg/kg of mefloquine tablets. High-grade (RII and RIII) resistance was observed in eight (40%) of the 20 patients receiving the single dose of arteflene, but in none of the 21 mefloquine-treated patients (P < 0.005). At day 28, only one patient in the arteflene group, compared with all 21 patients in the mefloquine group, was cured (P < 0.001). Arteflene cleared fever slightly but not significantly faster than mefloquine and the 50% and 90% parasite clearance times were comparable in both treatment groups. In vitro results in the arteflene group suggest an increase of arteflene resistance when comparing sensitivity of paired parasite isolates before treatment and at recrudescence. Both treatment regimens were well-tolerated. In conclusion, single dose monotherapy with arteflene was not effective in curing children suffering from uncomplicated P. falciparum malaria in Gabon, while mefloquine proved to be highly effective for this purpose.

Safety, immunogenicity, and pilot efficacy of Plasmodium falciparum sporozoite and asexual blood-stage combination vaccine in Swiss adults.

This study was part of a larger program to develop a vaccine effective against Plasmodium falciparum infection caused by sporozoites and clinical malaria caused by asexual blood stages. In a phase 1 study of safety and immunogenicity, two recombinant proteins (Ro 46-2717, a circumsporozoite [CS] protein) construct with a molecular mass of 35 kD, and Ro 46-2924, a merozoite surface antigen [MSA-2] construct with a molecular mass of 25 kD) adsorbed onto alum were injected in two low (20 micrograms) or two high (100 micrograms) doses in the right and left deltoid muscles of 33 healthy Swiss volunteers; six other volunteers received a placebo (alum alone). Twenty-six participants reported 51 immunization-related adverse events, mainly pain at the injection site. Mean antibody titers to CS protein and MSA-2 in an indirect immunofluorescence assay peaked four weeks after the second immunization without evidence of boosting (i.e., sharp increase in titer). By that time, 56% and 31% of the vaccinees seroconverted to CS protein and MSA-2, respectively, with the increase in MSA-2 titer being weaker than that for the CS protein. After a third immunization, five vaccinees volunteered to be challenged by three or four infective bites of Anopheles stephensi. Prepatent and incubation periods in all five were comparable with unvaccinated historic controls challenged under similar conditions, and all had symptoms of clinical falciparum malaria. We conclude that the vaccine components were safe and immunogenic but there was no evidence that this immunization regimen with the CS protein plus MSA-2 component was able to prevent infection.(ABSTRACT TRUNCATED AT 250 WORDS)

How frequent are notified severe cutaneous adverse reactions to Fansidar?

An attempt was made to estimate the risk of severe cutaneous adverse reactions (SCARs) to Fansidar (sulfadoxine plus pyrimethamine). Cases were identified through a spontaneous reporting system. Persons exposed were estimated using sales data of 27 countries reporting one SCAR case for either Fansidar or a related product, Bactrim (cotrimoxazole; sulfamethoxazole plus trimethoprim). Between 1974 and 1989, 126 cases were notified for Fansidar: 87 cases of erythema multiforme or Stevens-Johnson syndrome, and 39 cases of toxic epidermic necrolysis. 86% of cases were reported in Europe or North America. In 116 cases with use known, prophylaxis was the reason in 103, and treatment in 13. Toxic epidermolysis and erythema multiforme/Stevens-Johnson syndrome had case fatalities of 36 (95% confidence intervals 21 to 53%) and 9% (4 to 18%), respectively. Fansidar users were estimated at 117 million, and the overall SCAR risk to be 1.1 (0.9 to 1.3) per million. For developing countries with mainly single dose use, the risk was estimated to 0.1 (0.0 to 0.1) per million. For Europe and North America with mainly prophylactic use, the risk was 10 (8 to 12) and 36 (23 to 48) per million, respectively. Prophylactic use had a 40 times higher risk than single dose therapeutic use. The aggregated risk peaked in 1984-1985, with global and North American SCAR frequencies of 3.4 (2.4 to 4.3) and 72 (41 to 102) per million, respectively. After 1985, North America reported only one further case despite continued use by an estimated 0.3 million persons.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunodiagnosis of schistosomiasis outside endemic areas: use of histamine release from basophils by schistosomal antigens and radioallergosorbent test.

Specific allergic histamine release from leucocytes, radioallergosorbent tests (RAST) and indirect fluorescent antibody tests (IFAT) were applied for immunodiagnosis of schistosomiasis in patients outside endemic area. Of 10 parasitologically verified cases--all of them exhibiting a low and irregular egg output--8 were detected by histamine release, whereas 4 patient with filariasis, 3 with trichuriasis and 31 parasitologically normal controls were negative in this respect. By a combination of the histamine release test, RAST and IFAT all 10 cases were diagnosed. RAST and IFAT applied to 29 patients with active or treated schistosomiasis were positive in 14 (48%) and 20 (69%) cases, respectively.

The influence of schistosomiasis on the serum concentrations of retinol and retinol binding protein of a rural population in Liberia.

121 persons from rural areas of central Liberia were examined for possible interactions between helminthic infections and the retinol (vitamin A) and retinol binding protein (= RBP) status. About 2/3 of this mainly adult population had retinol and RBP serum concentrations less than or equal to 400 micrograms/l and less than or equal to 40 micrograms/ml, respectively. Only one person had a serum retinol concentration less than 100 micrograms/l which is critical for the appearance of xerophthalmia. The retinol and RBP concentrations showed a linear, positive correlation. 19 parasitologically helminth free individuals had mean serum retinol and RBP concentrations of 414 micrograms/l and 43 micrograms/ml, respectively, while the corresponding values of 20 individuals with schistosomiasis as the only helminthic infection were 339 micrograms/l and 35 micrograms/ml. 65 other persons with mixed intestinal and/or tissue helminthiases, and 9 persons with pure Onchocerca volvulus infection exhibited intermediate mean concentrations. 32 persons without serological evidence of helminthic infections had higher serum concentrations of retinol and RBP than 32 individuals in whose sera at least one raised antibody titer was found in the enzyme-linked immunosorbent assay with 3 different helminthic test antigens. In addition to age, sex and pregnancy schistosomiasis might be a further risk factor of latent retinol and RBP deficiency among adults and teenagers living in a schistosomiasis endemic area.

A longitudinal study on relations of retinol with parasitic infections and the immune response in children of Kikwawila village, Tanzania.

From 1982 to 1984 170 children of Kikwawila village (Kilombero district, Tanzania) were followed for nutritional (anthropometric measures, hematocrit, serum retinol, prealbumin, and zinc concentrations), parasitological (malaria parasitemia, urinary schistosomiasis, intestinal parasites) and immunological characteristics. Between 2.9% and 12.4% had serum retinol levels less than 100 micrograms/l which indicate deficiency. Retinol concentrations were correlated with age, hematocrits, prealbumin levels and mid upperarm circumferences. The latter correlation may be useful in nutritional surveys and primary health care programs for the identification of populations at risk of retinol deficiency. No association was found between average retinol levels and the presence of parasites, with the exception of malaria. Retinol levels were inversely correlated with malaria parasitemia in 1982, and directly correlated with antibody titers to synthetic sporozoite peptide in 1984. Since retinol, malaria parasitemia, and antisporozoite antibodies increased with age, confounding by age could not be excluded. Six months after administration of ornidazole in a single oral dose of 10 mg/kg, a significant effect on the prevalence of Giardia lamblia was found. Following treatment, average retinol levels were increased in persons with confirmed G. lamblia infections, but not in uninfected or untreated controls.

[Parasitic disease in schoolchildren in a village in Swiss Jura]. / Parasitosen bei Schulkindern in einem Schweizer Juradorf.

In a village of the Swiss Jura we examined 134 schoolchildren (7 to 16 years old) clinically, parasitologically and serologically for parasites. Half of the children showed an insufficient hygiene of hands, feet and/or anus. In 7 out of 107 anus-scotch-tests there were eggs of Enterobius vermicularis. Protozoans could be demonstrated in 8 of 133 MIF-stool-samples (2 cases of Giardia lamblia, 2 Endolimax nana and 4 Jodamoeba bütschlii). Using the procedure of enrichment of Telemann no helminth eggs were detected. Altogether parasites were found in 10% of the children. 31 children have antibodies against Toxoplasma gondii (IF titre greater than or equal to 1:40). 5 children showed a positive Toxocara-serology, additional 5 an uncertain positive reaction. The immunodiagnostic of Echinococcosis (ELISA, IF, IHA, CIE) was doubtfully positive in 4 children. In this study, intestinal protozoans and E. vermicularis were the most commonly occurring parasites followed by asymptomatic toxocariasis.

Prevention of Plasmodium falciparum malaria by Fansimef and Lariam in the northeastern part of Thailand.

Two studies were conduct in Thailand in order to find appropriate falciparum malaria prophylactic drug regimens. The first study was done during June - September 1987 with 363 soldiers who received Fansimef (MSP) 1 tab/week (group 1), 337 soldiers who received MSP 1 tab/2 week (group 2) and 165 soldiers who received chloroquine 300 mg base weekly plus Fansidar 1 tab/week (group 3). At the end of the study there were 9 and 13 falciparum malaria episodes in groups 1 and 2, respectively, with incidence rates of 0.8 and 1.8 cases/100 person-months (P-M). In group 3, the corresponding values were 30 episodes and an incidence of 7.2/100 P-M. For the second study which lasted from October 1987 - January 1988 in the same area, 498 soldiers were given Fansimef 1/2 tab/week (group 4), 499 soldiers were given Lariam 1/2 tab/week (group 5) and 247 soldiers were given chloroquine plus Fansidar (group 6). Thirty malaria episodes were found in group 4, for an incidence of 2.0/100 P-M. In group 5, 23 episodes were found, for an incidence of 1.6/100 P-M. In group 6, 74 episodes occurred, ie an incidence of 12.2/100 P-M. The incidence rates of malaria among Fansimef 1 tab weekly, Fansimef half dose weekly or Lariam half dose weekly were not significantly different but were different from chloroquine plus Fansidar groups. Adverse events in each group were mild.

Fansimef for prophylaxis of malaria: a double-blind randomized placebo controlled trial.

At a time when Fansimef, the fixed combination of mefloquine, sulfadoxine and pyrimethamine was considered for prophylaxis of falciparum malaria, a randomized double-blind study comparing the efficacy and tolerability of Fansimef with that of Lariam (mefloquine), Fansidar, chloroquine and placebo in malaria prophylaxis was performed in Thailand from July 1987 to January 1988. The study population of 602 adult males was recruited in Pak Tongchai District, some 360 km North-East of Bangkok, where multiresistant P. falciparum is endemic. All active treatments and placebo were given once weekly for 24 weeks with doses as follows: Fansimef: 125 mg mefloquine + 250 mg sulfadoxine + 12.5 mg pyrimethamine (1 half-strength tablet); Lariam: 125 mg mefloquine (1 half-strength tablet); Fansidar: 500 mg sulfadoxine + 25 mg pyrimethamine; chloroquine; 300 mg. A loading dose of 2 half-strength tablets was given in the Fansimef group in weeks 1 and 2 and in the Lariam group in weeks 1 to 4. The incidence of acute episodes of P. falciparum per 100 person months of prophylaxis was 0.17 each in the Fansimef and the Lariam groups, 1.18 in the Fansidar group, 0.69 in the chloroquine group and 0.64 in the placebo group (differences statistically not significant). Clinically adverse events were reported by 170 subjects (Fansimef 28, Lariam 29, Fansidar 41, choroquine 43, placebo 29; differences statistically not significant). The most frequent adverse events in all groups were headache, sleepiness, dizziness and weakness.(ABSTRACT TRUNCATED AT 250 WORDS)

[Vaccination against malaria: initial trial with an ant-sporozoite vaccine, (NANP)3-TT (RO 40-2361) in Africa (Bobo-Dioulasso, Burkina Faso)]. / Vaccination contre le paludisme: premier essai avec un vaccin antisporozoïte, le (NANP)3-TT (RO 40-2361) en Afrique (Bobo-Dioulasso, Burkina Faso).

The vaccine (NANP)3-TT is a synthetic peptide of the circumsporozoite protein (CS) of Plasmodium falciparum coupled to tetanus toxoid (TT) as protein carrier and adsorbed to aluminium hydroxide as adjuvant. The objectives of the study were to assess the immunogenicity and the protective efficacy of the vaccine in an area where malaria is endemic. The study was conducted in a zone of irrigated rice cultivation known as the Vallée du Kou to the North of Bobo-Dioulasso. Malaria transmission is permanent in the Vallée with maxima in July and November. The study was conducted from June to December 1988. It was a controlled randomised, double blind, prospective vaccine trial. A total of 123 infants from 3 to 5 months of age were randomly assigned to three groups. Group I (controls) received three doses of TT alone, group II received two doses of TT and one of (NANP)3-TT and group III received three doses of (NANP)3-TT. These vaccines were administered simultaneously with the Enlarged Program of Immunisation (EPI) vaccines. The clinical parasitological and immunological status of the children was then monitored over a period of five months. No systemic reactions to the vaccine were observed in the infants either immediately after administration or during the follow-up. Minor local tumefactions were observed in only 3% of the children. The vaccine was found to be immunogenic with a peak IgG response at day 75, when 56% (group II) and 60% (group III) showed antibody titres of at least four times that seen at day 0. The response, however, was a short duration; by day 150 the average antibody titres were not significantly different between the three groups. The incidence and the level of parasiaemia and the incidence of clinical malaria were also not significantly different for each of the three groups during the period of the study. The association of (NANP)3 with tetanus toxoid was not shown to be immunologically inhibitive. The results, despite not showing a protective effect for the vaccine (NANP)3-TT, have shown its immunogenicity and therefore suggest that further development of this vaccine may be worthwhile.

[Malaria--chemoprophylaxis 2001]. / Malaria-Chemoprophylaxe 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.

[An unusual case of imported malaria]. / Ein ungewöhnlicher Fall von importierter Malaria.

We report a case of malaria occurring after a journey to Guadeloupe, an island, which is considered as being free of malaria. The case report serves to remind that previous areas of endemicity remain receptive for malaria, and that one has to consider malaria in the differential diagnosis of a feverish illness even when a traveller returns from a country where malaria transmission has not been reported.

[Emergency treatment of malaria during travel]. / Notfallmässige Behandlung der Malaria auf Reisen.

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.

[Current drugs for the treatment of tropical malaria]. / Neue Medikamente für die Behandlung der Malaria tropica.

The occurrence in the early 60's of stable resistance to chloroquine among Plasmodium falciparum strains in the Amazonas and on the Thai-Cambodian border has been a shock for all malariologists. This led to the search for new antimalarials without cross resistance with chloroquine. For each new drug, one of the major concerns was to define how rapidly parasites would develop resistance to this compound. Drug combinations were taken into consideration so as to achieve a delay in the appearance of resistance. The decision to test a triple combination has led to the development of Fansimef, a fixed combination with tablets containing 250 mg mefloquine, 500 mg sulfadoxine and 25 mg pyrimethamine. A very relevant delay in the development of resistance was found both in-vivo--in the P. berghei model--and in-vitro using P. falciparum. Fansimef has also been under investigations for malaria. Controlled clinical trials were performed in Africa, South America and South East Asia. The documentation for this new indication will be submitted to registration authorities in 1991. A preference alternative to continuous chemoprophylaxis is stand-by malaria treatment for travellers to regions where the malaria risk is relatively low. Stand-by treatment is under investigations in France and in Switzerland. In the search for alternative remedies against drug resistant P. falciparum malaria our attention was directed to Yingzhaosu, a new sesquiterpene peroxide of plant origin from traditional Chinese medicine. A short and convenient synthesis of this ring system gave access to a variety of structural analogues of Yingzhaosu.(ABSTRACT TRUNCATED AT 250 WORDS)