Malaria is the world's most important parasitic disease, imposing a massive health burden on people living in the tropics, often in the poorest countries. The vast majority of deaths in humans from malaria are caused by one species of the hemoprotozoan, Plasmodium falciparum., against which effective control measures are urgently needed. The global situation has deteriorated in recent times due to increased resistance of the anopheline mosquitoes that transmit P. falciparum to insecticides, and of the parasites themselves to drug therapy. An efficacious and cost-effective vaccine against this parasite is considered a public health priority. A vaccine that targets pre-erythrocytic parasites in the liver could potentially prevent clinical disease by blocking development of the pathogenic erythrocytic stage of the parasite's life cycle. Among around 40 known P. falciparum antigens, liver stage antigen-1 (LSA-1) is the only protein expressed exclusively by liver stage parasites. Independent studies in humans have consistently related immune responses to LSA-1 with resistance to malaria infection or disease, providing a powerful rationale for the development of liver stage vaccines based on LSA-1. By dissecting the mechanism(s) of immunity to this antigen, epitopes associated with protection can be evaluated in different delivery systems as components of a focused and coordinated multi-antigen malaria vaccine strategy.

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Camel trypanosomosis (Surra) is one of the most important diseases affecting camel calves. It presents itself as an acute form and is usually fatal if treatment is not carried out. A study was initiated at Mogwooni ranch in Laikipia district of Kenya to survey the prevalence of trypanosomosis in camel calves of mixed breeds, and to evaluate the microhaematocrit centrifugation technique (MHCT), monoclonal antibody based card latex agglutination test (Suratex®), wet smear and mouse inoculation (MI) in the diagnosis of the disease in camels. The tests were assessed for a period of 16 months. The mean Trypanosoma evansi prevalence ranged from 4.5% as determined by the wet smear, 11.1% by MHCT, 14.6% by MI, to 28.3% by Suratex®. Young calf death rate due to trypanosomosis was 12.3% while overall mortality rate was 15.0%. The cost of veterinary care (anti-helminthics, acaricides and trypanocides) was on average US$ 4.6 per calf per year. It is thus recommended that diagnosis accompanied by proper treatment be carried out routinely for the survival of camel calves in trypanosomosis endemic areas.

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We investigated the presence of Babesia microti and B. divergens in Ixodes ricinus ticks collected in a Lyme borreliosis endemic area of Northern Poland. We used as the PCR target the fragment from a gene encoding the nuclear small-subunit ribosomal RNA (SS-rDNA). We have made a thorough analysis of the quantitative and rate per cent occurrence Ixodes ricinus from two areas of forest in province of Szczecin, known as highly recreative and frequented of many people resort. A total of 533 specimens collected in 13.3% was detected DNA of B. microti and in 3.0% of B. divergens.

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A cross-sectional survey of 29 randomly selected schools, comprising 11 (37.9%) post-primary schools and 18 (62.1%) primary schools from eight Local Government Areas (LGAs) (approximately 35% of the 23 LGAs) of Kaduna State was undertaken to determine the prevalence status of cutaneous leishmaniasis between May and October, 1997. The disease occurrence was detected by on-sight diagnosis of active lesions and scars, and observed leishmanial cases were recorded for patients who gave description of symptoms that fitted into clinical symptoms of cutaneous leishmaniasis. The recorded cases were confirmed by parasitological examination of Giemsa-stained lesion smears for amastigotes in the laboratory. The Chi-square analysis of the result revealed that there was no significant difference (P>0.05) in the point prevalence (PP) rates (number with active lesions) between the males (3.8% of 6,104) and the females (4.0% of 4,122). Similarly, the overall prevalence (OP) rate (number with both scars and active lesions) in the state was estimated at 6.8% (697), and there was no significant difference (P>0.05) observed between the males (6.4% of 6,104) and females (7.5% of 4,122). The point prevalence rate was higher in the younger age-groups (6-9, 10-12, 13-15 years old) than in the older one (16-18 years old) while the overall prevalence and lifetime prevalence (LTP) (number with scars only) decreased with age. It was also noted that the diagnostic efficiency of the on-sight clinical screening tests and that of the parasitological examination of lesion smears compares favourably well. The results of this study have indicated that the prevalence of cutaneous leishmaniasis in Kaduna State is high enough to consider the state endemic for the disease, and that with experience the on-sight case detection of leishmanial lesions can be dependably applied as a rapid diagnostic method for cutaneous leishmaniasis in field research.

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