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Mini mental state tests (MMS) were administered to 227 adults over the age of 40 years living in an Ecuadorian urban Andean community known to be an endemic zone for Taenia solium taeniasis and cysticercosis. The overall prevalence of cognitive impairment was 8.4% (19/227). The prevalence of cognitive impairment was 23.5% (8 cases) in adults over 75 years (n=34). The Hachinski ischemic score for vascular dementia was abnormal in 4 of the 19 adults (21%) exhibiting cognitive impairment. This survey highlighted a high prevalence of dementia in comparison with industrialised countries. Parasitic encephalopathy that was present in one out of five persons in this Andean community could play a part in early damage of cognitive function.

Taenia solium neurocysticercosis (NCC) has been documented to be an underlying cause of epilepsy, intractable headaches, hydrocephalus, dementia and other serious neurological conditions in many countries of Central and South America. However, methodological limitations had prevented the assessment of the true prevalence of this condition at the community level. We conducted a house-to-house neuroepidemiological survey of 6,118 residents of an Andean community. This information was used to target neuroimaging (CT-scan) and immunodiagnosis (enzyme-linked immunoelectrotransfer blot assay, EITB) tests in individuals suspected of harbouring Taenia solium NCC. In the rural population, NCC was confirmed in 8 out of 47 examined by CT-scan (17%) and in 6 of 42 examined by EITB (14%). In the urban population, NCC was confirmed in 35 of 147 examined by CT-scan (23.8%) and in 28 of 124 examined by EITB (22.6%). In a sample of relatives of patients with documented cerebral cysticercosis, 20 out of 81 examined by CT-scan (25%) and 12 of 79 (15%) examined by EITB had NCC. Finally, CT scans were performed for 83 school children from urban areas, and 9 (11%) were diagnosed as harbouring NCC. In a community-based study, cysticercosis appears to be much more frequent than initially thought, when CT examination is used as the "gold standard" for diagnosis.

Four weekly injections of 50 micrograms of trehalose dimycolate (TDM) in FIA protect 40% of the Mice against a lethal infection by Trypanosoma cruzi; under the same conditions MDP (muramyldipeptide) has only a very slight effect.

Les femelles de la coccinelleSemiadalia undecimnotata Schneider ingerent environ 20 mg d'aphides par jour a 22°C lorsqu'il y a surabondance de proies. Dans les premiers jours qui suivent la mue imaginale, ces prises alimentaires provoquent une augmentation sensible du poids corporel des femelles qui par la suite oscille autour d'une valeur moyenne relativement stable. La rapidite de la maturation depend de la ration alimentaire disponible pour les femelles. L'emission des premiers œufs se produit lorsque les femelles ont ingere de 70 a 90 mg de proies. Pendant la periode de ponte, il existe une relation lineaire etroite entre la consommation alimentaire et la ponte exprimees en poids frais et sous forme cumulee. Elle pourrait permettre d'envisager le denombrement des œufs produits par les femelles comme un moyen d'estimer partiellement leur activite trophique. Toutefois au sein de la population consideree, les aptitudes reproductrices sont tres heterogenes. Cette variabilite, qui est observee dans des conditions constantes d'elevage et qui est independante du poids initial des individus, pourrait etre d'origine genetique: dans cette eventualite, il est peut-etre possible de selectionner les femelles en fonction de leur efficacite trophique ou de leurs capacites reproductrices.