ABSTRACT
BACKGROUND: Plasmodium falciparum genetic diversity and multiplicity of infection (MOI) are parasite features that have been suggested to influence the acquisition of protective immunity against malaria. This study sought to assess the relationship between MOI and parasite density (PD) in malaria patients living in the Central Region of Ghana and to determine whether naturally occurring antibody levels against P. falciparum GLURP (PF3D7_1035300) and MSP3 (PF3D7_1035400) antigens are associated with decreased parasite load. METHODS: Dried filter paper blood blots were obtained from children and adults diagnosed with uncomplicated P. falciparum malaria. Microscopy was used to estimate P. falciparum parasite density and polymerase chain reaction (PCR) amplification of the polymorphic regions of msp1 (PF3D7_0930300) and msp2 (PF3D7_0206800) was used for parasite genotyping and MOI determination. ELISA was used to measure the serum IgG concentration of R0 fragment of GLURP (GLURP(R0)) and MSP3 antibodies. RESULTS: All 115 samples were positive for P. falciparum by PCR using either the msp1 or msp2 genotyping primer sets. The most prevalent msp1 and msp2 alleles were KI and 3D7, respectively. The geometric mean (GM) for MOI determined by both msp1 and msp2 genotyping was 1.3 for the entire population and was generally higher in children than in adults. Seropositivity was estimated at 67 and 63% for GLURP(R0) and MSP3 antibodies, respectively, and antibody titers were negatively correlated with parasite density. CONCLUSIONS: The negative correlation between naturally occurring GLURP(R0) and MSP3 antibody levels and parasite density observed in this study suggest that augmenting the antibody response with the GMZ2 vaccine could enhance protection in the Central Region of Ghana.
Subject(s)
Antigens, Protozoan/immunology , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Parasite Load , Plasmodium falciparum/immunology , Plasmodium falciparum/physiology , Protozoan Proteins/immunology , Adolescent , Adult , Animals , Antigens, Protozoan/genetics , Child , Child, Preschool , Dried Blood Spot Testing , Enzyme-Linked Immunosorbent Assay , Female , Genetic Variation , Genotype , Ghana/epidemiology , Humans , Immunoglobulin G/blood , Infant , Malaria Vaccines/immunology , Malaria, Falciparum/epidemiology , Male , Merozoite Surface Protein 1/genetics , Plasmodium falciparum/genetics , Polymerase Chain Reaction , Protozoan Proteins/genetics , Young AdultSubject(s)
Antibodies, Viral/blood , HIV Infections/virology , Herpesviridae Infections/epidemiology , Herpesvirus 8, Human/immunology , Sarcoma, Kaposi/epidemiology , Adult , Female , Ghana/epidemiology , HIV Infections/complications , Herpesviridae Infections/complications , Humans , Male , Prevalence , Sarcoma, Kaposi/complications , Seroepidemiologic StudiesABSTRACT
In West African countries such as Ghana, efficient human immunodeficiency virus (HIV) testing is a priority in the fight against AIDS. A new immunochromatographic rapid test, Determine HIV-1/2 (Abbott Diagnostics, North Chicago, Ill.), that detects antibodies against HIV type 1 (HIV-1) and/or HIV-2 was evaluated using Ghanaian blood samples. Two hundred four serum and/or plasma specimens were tested. HIV screening was done by a particle agglutination test and confirmed by a Western blot (WB) test as the "gold standard." The results revealed 125 HIV-seropositive AIDS patients, 75 HIV-seronegative healthy individuals, and 4 individuals for whom the HIV-1 result was indeterminate. The results obtained by the Determine HIV-1/2 assay and Diagnostic HIV SPOT (Genelabs), which is currently widely used in many districts in Ghana, were compared with those of the WB test, excluding the four HIV-1-indeterminate samples. The sensitivity of the Determine HIV-1/2 assay was 100%, compared with 98.0% for the HIV SPOT assay. The specificity was 100% for both tests. Determine HIV-1/2 is a single-step assay and was found to be rapid and easy to perform without any special equipment. It was highly sensitive and specific. The kit can be applied without electricity and water supplies, making it suitable for the detection of HIV antibodies especially in the rural areas of Ghana, West Africa.
Subject(s)
AIDS Serodiagnosis/methods , HIV Antibodies/blood , HIV Infections/diagnosis , HIV-1/immunology , HIV-2/immunology , Chromatography , Ghana , HIV Infections/virology , Humans , Immunoblotting/methods , Sensitivity and SpecificityABSTRACT
In this paper, the Eimeria oocyst output of two groups, pregnant ewes (group 1) and non-pregnant controls (group 2), which were followed from September 1993 to August 1994, is described. In both groups of animals the level of oocyst output was high during the minor rainy season. However, during the periparturient period the pregnant ewes showed the higher oocyst output. The oocyst output in both group fell to similar levels after weaning of the lambs in March 1994. The species of Eimeria identified in order of dominance were Eimeria parva, E. pallida, E. faurei, E. ahsata, E. ovina, E. intricata, E. granulosa and E. ninakohlyakimovae. There were no differences in the species composition of oocysts in both groups of animals.
