A Probe into Protective Association of Haemoglobin Genotypes with Malaria Parasitaemia among Students of a University in Western Delta, Nigeria

Abstract

Aim: This work was designed to investigate any possible protective association of haemoglobin genotypes with malaria parasitaemia among students of a private University in Western Delta. Study Design: Whole blood samples were obtained from a cross section of students by simple random sampling method. Collected blood samples were dispensed into ethylene-diamine-tetra-acetic acid (EDTA) containers which were appropriately labelled. Collected blood samples were tested for haemoglobin genotypes and malaria parasites by standard methods. Data obtained were statistically analysed. Place and Duration of Study: The study was carried out in the Microbiology and Biotechnology laboratory of Western Delta University, Oghara, Nigeria between May, 2013 to October, 2013. Methods: Venous blood (2ml volume) was obtained by venipuncture from 360 symptomatic and asymptomatic students made of 150(41.7%) males and 210(58.3%) females with a mean age of 23.5±8.5 years. Malaria parasite screening was done by both Plasmodium falciparum antigen rapid (Micropoint, USA) test and Giemsa staining. Haemoglobin genotyping was done by a modified cellulose acetate membrane electrophoresis (CAME) method. Results: A total of 225(70.8%) students were infected with trophozoites and other forms of P. falciparum parasites of which 53.3% and 44.7% were infected females and males respectively. There was significant association between sex and malaria infection rates (P<0.05). Two hundred and forty (66.7%), 99(27.5%) and 21(5.8%) students were of HbAA, HbAS, and HbSS genotypes. Sixty five (18.1%) HbAA male and 99(27.5%) HbAA female students were infected with malaria parasites. Thirty nine (10.8%) and 21(5.8%) male HbAS and female HbAS students respectively were infected with malaria parasites. Eight (2.2%) and 7(1.9%) male HbSS and female HbSS students respectively were infected. Malaria infection rates among types were HbAA (45.6%), HbAS (16.7%) and HbSS (4.2%). Age groups 21-25 and 15-20 had the highest malaria infection rates and population of HbAA, HbAS and HbSS students while 41-45 group had the least. Chi square analysis showed that there was no significant association between male and female HbAA, HbAS, HbSS and malaria infection rates (HbAA X2 0.05,10= 7.786, HbAS X20.05, 10= 8.421, HbSS X20.05, 10= 4.1, P-value 0.05, 10 =18.307, Hence P>0.05). Conclusion: Findings in this work are suggestive that Oghara town may be hyper endemic for malaria and this information may be useful to the University Health department as well as the relevant Delta State Health agencies for the necessary antimalarial therapy and prophylactic measures. Findings also indicate a high prevalence of haemoglobin genotype variants particularly heterozygous HbAS. This information can help in the formulation of genetic counseling policies for prospective couples in order to assist them make informed decisions before marriage. This will ultimately reduce the sickling gene pool amongst the study population and beyond. Results of this study also imply that there is no protection against malaria by any of the implicated haemoglobin genotypes.