Current status of malaria parasite among blood donors in Port Harcourt, Rivers State, Nigeria

This study was carried out to determine the prevalence of malaria parasite among blood donors at the Police Clinic Port Harcourt, Rivers State, Nigeria. The standard parasitological techniques using both thick and thin blood films from the donors for the detection of malaria parasite was followed. Venous blood was collected from 200 blood donors and films were made on clean greese-free glass slide and stained with 10%Giemsa stains and viewed under the microscope using the oil immersion objective. Of the 200 samples examined, 56 (28.00%) were positive with Plasmodium falciparium . The highest prevalence among the males 53(26.50%) and between the ages 21-30years and only 3 (1.50%) of females were positive. Donors having the blood group O were more infected (60.70%) than the other blood groups and the lowest was blood group AB (5.40%). This result shows that there is a relatively high prevalence of malaria parasite among the blood donors in Port Harcourt, Nigeria. It is, therefore, recommended that malaria parasite screening test be included among other blood screening tests before any transfusion to avert the deleterious effects of malaria on recipients.

Immunoregulation in human malaria: the challenge of understanding asymptomatic infection

Asymptomatic Plasmodium infection carriers represent a major threat to malaria control worldwide as they are silent natural reservoirs and do not seek medical care. There are no standard criteria for asymptomatic Plasmodium infection; therefore, its diagnosis relies on the presence of the parasite during a specific period of symptomless infection. The antiparasitic immune response can result in reduced Plasmodium sp. load with control of disease manifestations, which leads to asymptomatic infection. Both the innate and adaptive immune responses seem to play major roles in asymptomatic Plasmodium infection; T regulatory cell activity (through the production of interleukin- 10 and transforming growth factor-β) and B-cells (with a broad antibody response) both play prominent roles. Furthermore, molecules involved in the haem detoxification pathway (such as haptoglobin and haeme oxygenase-1) and iron metabolism (ferritin and activated c-Jun N-terminal kinase) have emerged in recent years as potential biomarkers and thus are helping to unravel the immune response underlying asymptomatic Plasmodium infection. The acquisition of large data sets and the use of robust statistical tools, including network analysis, associated with welldesigned malaria studies will likely help elucidate the immune mechanisms responsible for asymptomatic infection.