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L Haller

Publications and source records attributed to L Haller.

At least 19 recordsLinked to original sources
PubMed2000

Towards an atlas of human helminth infection in sub-Saharan Africa: the use of geographical information systems (GIS).

The value of a geographical perspective to infectious disease epidemiology and control has long been recognized. However, the labour required to produce maps, and keep them up to date, has inhibited the development of this area, and very little is currently known about the spatial distribution of parasitic infections other than malaria, trypanosomiasis and onchocerciasis. A recent initiative by an international group of collaborators is attempting to redress the absence of detailed spatial information on the major helminth infections of humans. In this article, Simon Brooker and colleagues describe progress made by this initiative in mapping helminth infections in sub-Saharan Africa, highlighting the value as well as the limitations of this empirical mapping approach.

Africa South of the Sahara↗
PubMed1999

Efficacy and tolerability of a low-dose mefloquine-sulfadoxine-pyrimethamine combination compared with chloroquine in the treatment of acute malaria infection in a population with multiple drug-resistant Plasmodium falciparum.

The efficacy and tolerability of single, low-dose mefloquine, sulfadoxine-pyrimethamine (MSP) combination was compared with chloroquine (CQ) for malaria treatment in a malaria-endemic area of Nigeria with multiple drug-resistant Plasmodium falciparum. The two drug regimens (MSP and CQ) were tested in a 12-month prospective population study. The patients were divided into two groups. Group 1 patients were treated presumptively, based on malaria symptoms. Group 2 patients were treated based on a parasitologic diagnosis using the World Health Organization seven-day in vivo test and extended to a 28-day follow-up period. Tolerability was assessed by the incidence and intensity of adverse events. One thousand nine hundred thirty-five patients visiting 10 health facilities, including the University of Calabar Teaching Hospital, were enrolled. The study showed that the low-dose MSP was efficacious, with day 7 response rates of 95% and 91% for (presumptive) Group 1 and (in vivo) Group 2, respectively, while CQ had day 7 response rates of 82% and 66% in Groups 1 and 2, respectively. The low-dose MSP was significantly (P < 0.0001) more efficacious, with faster fever and parasite clearance times than CQ in this area of CQ-resistant P. falciparum malaria. Eight patients treated with CQ, including seven severe cases (RII-RIII) were successfully re-treated with MSP. Adverse events were generally more common among those treated with MSP (29%) than those treated with CQ (17%). However, the adverse events caused by both drugs were mild to moderate and self-limited. The MSP combination appears to be a good substitute for CQ, in view of multiple drug resistance, especially in areas with severe (RII-RIII) malaria.

Adolescent↗
PubMed1995

Mefloquine in the Prophylaxis of P. Falciparum Malaria.

Background: The objectives of this study were (1) to compare the efficacy of Lariam (mefloquine) with that of Fansimef (mefloquine, sulfadoxine, and pyrimethamine), Fansidar (sulfadoxine and pyrimethamine), chloroquine, and placebo in suppressing asexual parasitemia in semi-immune persons living in an area endemic for Plasmodium falciparum malaria; and (2) to compare the tolerance of these drugs when taken over a prolonged period of time. Method: A randomized double-blind comparative placebo-controlled study was undertaken in the village of Biasso, 60 km from Abidjan in the southern part of the Ivory Coast, a region where P. falciparum malaria is endemic. Four hundred and ninety nine male volunteers (five parallel groups), who were inhabitants of Biasso, were involved. The main outcome measures concerned the incidence of malaria breakthroughs (acute malaria attacks) and the incidence of parasitemia. Results: Within this strictly defined epidemiologic context, prophylaxis, taken once weekly, proved to be fully protective (parasitic index: 0) in the Lariam, Fansidar, and Fansimef groups throughout the whole study period. Prophylaxis with chloroquine proved incompletely protective (parasitic index: 2.5) The most frequent side effects were pruritus (5.6%), diarrhea (1.2%) and headache (0.06%). No significant differences in the incidence of side effects in each group (chi-square test) was observed. All side effects were transient and judged to be mild by the investigators. Conclusions: Excellent efficacy was observed in the prophylaxis of P. falciparum malaria with Lariam, Fansidar, and Fansimef as compared to the partial protection provided by chloroquine. Safety and tolerance were comparable in all groups during the whole period of observation (5 months).

Journal Article↗
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↗
PubMed1990

[Vaccination against malaria: initial trial with an ant-sporozoite vaccine, (NANP)3-TT (RO 40-2361) in Africa (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.

Animals↗
PubMed1986

Clinical and pathological aspects of human African trypanosomiasis (T. b. gambiense) with particular reference to reactive arsenical encephalopathy.

Fourteen of 330 patients treated with melarsoprol (Mel B) for human African trypanosomiasis (HAT) developed a severe reactive arsenical encephalopathy (RAE). Six of these cases were fatal and postmortem examination was performed on 5 patients. Symptoms of "sleeping sickness" were compared with symptoms after treatment with arsenicals and the subsequent onset of RAE. There are 3 characteristic syndromes of RAE: convulsive status associated with acute cerebral edema, rapidly progressive coma without convulsions, and acute nonlethal mental disturbances without neurological signs. Three subjects revealed hypoxic brain damage with acute cerebral edema, and multiple hemorrhages of brain stem in those comatose. The pathology of the underlying HAT (chronic perivascular inflammation and plasma cytic infiltration of the brain) and the pathology of the RAE (characterized by acute vasculitis) are distinct. RAE occurs in the first as well as in the second stage (CNS involvement) of trypanosomiasis but the reason for this is unclear; an exclusive toxicity of the drug, or a Herxheimer reaction are possible but seem unlikely. Both clinical and laboratory findings point rather to a drug-related, delayed immune response.

Animals↗
PubMed1981

Epidemiological studies on the animal reservoir of gambiense sleeping sickness. Part I. Review of literature and description of the study areas.

A review of literature of the previous and recent evidence of potential animal reservoir hosts of gambiense sleeping sickness is given. A highly endemic sleeping sickness area in the Ivory Coast is described together with an area of recent low endemicity in southwestern Upper Volta. These areas were surveyed as part of a study on the significance of any potential animal reservoir of the disease. The results are described in detail in subsequent papers.

Animals↗