Plasmodium falciparum: population genetic analysis by multilocus enzyme electrophoresis and other molecular markers.

Abderrazak, S. B., Oury, B, Lal, A. A., Bosseno, M.-F., Force-Barge, P., Dujardin, J.-P., Fandeur, T., Molez, J.-F., Kjellberg, F., Ayala, F. J., and Tibayrenc, M. 1999. Plasmodium falciparum: Population genetic analysis by multilocus enzyme electrophoresis and other molecular markers. Experimental Parasitology 92, 232-238. The population structure of Plasmodium falciparum, the agent of malignant malaria, is uncertain. We have analyzed multilocus enzyme electrophoresis (MLEE) polymorphisms at 7-12 gene loci in each of four populations (two populations in Burkina Faso, one in Sudan, one in Congo), plus one "cosmopolitan" sample consisting of parasite cultures from 15 distant localities in four different continents. We have also performed random amplified polymorphic DNA analysis (RAPD) and restriction fragment length polymorphism (RFLP) and characterized gene varia tion at four antigen genes in the Congo population. All genetic assays show abundant genetic variability in all populations analyzed. With the isoenzyme assays, strong linkage disequilibrium is apparent in at least two local populations, the Congo population and one population from Burkina Faso, as well as in the cosmopolitan sample, and less definitely in the other Burkina Faso population. However, no linkage disequilibrium is detected in the Congo population with the molecular assays. We failed to detect any nonrandom association between the different kinds of genetic markers; that is, MLEE with RAPD or RFLP, RAPD with RFLP, and so on. Although isoenzyme data show statistical departures from panmictic expectations, these results suggest that in the areas under survey, P. falciparum populations do not undergo predominant clonal evolution and show no clear-cut subdivisions, un like Trypanosoma cruzi, Leishmania sp., and other major parasitic species. We discuss the epidemiological and taxonomical significance of these results.

Place des urgences medicales pediatriques dans un service medical a Pointe Noire

Les auteurs etudient les urgences medicales pediatriques chez les enfants ages de 0 a 15 ans dans un centre medico-social a Pointe Noire sur une periode de 5 ans (1988-1992). Ils constatent que les urgences medicales pediatriques representent 18;54 pour cent des admissions. Les principaux groupes etiologiques de ces detresses vitales sont par ordre de frequence les suivants: les urgences neurologiques (331 cas soit 52 pour cent); les urgences respiratoires (137 cas soit 21;5 pour cent); les urgences hematologiques (81 cas soit 12;70 cas) et les urgences gastro-enterologiques (73 cas soit 11;50 pour cent). Les autres urgences medicales pediatriques (etats infectieux severes: rougeoles; septicemies; urgences cardiologiques et les intoxications medicamenteuses severes) representent 2;30 pour cent des cas. La prevention des principales causes de ces detresses vitales; avant que les strategies preconisees par les soins de sante primaires et l'initiative de Bamako soient la cle de voute du systeme sanitaire dans notre region; passe par une education constante pour la sante

Evaluation of Testryp CATT applied to samples of dried blood for the diagnosis of sleeping sickness.

Described is an evaluation of the card agglutination test (Testryp CATT) applied to dried blood collected on filter-paper. The sensitivity of the test was compared for samples of diluted sera, whole blood and dried blood. Sera diluted 1:8 gave similar CATT results to those obtained with dried blood. The false negative rate was 5.8%, and test specificity, 100.0%. Use of CATT with samples of dried blood is recommended for screening populations at risk for trypanosomiasis in situations where specialized surveillance teams are not available to test sera or whole blood.