HAEMOPARASITOSIS, HELMINTHIASIS AND THEIR PLASMA CYTOKINES RESPONSES IN HUMANS IN BAYELSA STATE, NIGERIA

The co-infection of malaria parasites and helminths is common in the tropics. Their pathogenicity lies in the infectivity of parasites and their modulation of the host immune system. This study aimed to generate epidemiological data of malaria and helminths in apparently healthy humans in a rural population in Bayelsa State; determine the serum concentration of Interleukin-4, Interferon-gamma -IFN-γ, Macrophage Inflammatory protein-MIP-β/CCL-4 and Eotaxin-3 /CCL 26 in healthy volunteers infected with malaria and helminths and their values after treatment. Two sets of data; malaria and helminths were generated from school and community based study, carried out between May 2016 and July 2018 in four rural communities- Otuegela, Immiringi, Otuesega and Ibelebiri in which there was ongoing mass deworming and anti-malaria administration. Ethical approval was obtained from the Ethical Committee, College of Medicine, University of Benin, Nigeria (CMS/REC/2017/016). From every participant, blood and stool samples were collected; from 1441 volunteers, age-range 4 – 80 years. Diagnosis of helminths, malaria parasites were by standard procedures. The body mass index (BMI) of children was determined. Measurement of haemoglobin concentration and blood cells was automated (ABX Micros 60). Infected volunteers were treated specifically and after 18 days the second round of blood and stool samples were collected from treated participants only and analyzed. Immune molecules were measured by ELISA (PeproTech, USA) protocols. Data were analysed with the "R" Programme (version 2016) and a P-value of < 0.001 was considered significant.  The prevalence of helminths was: community-based, 26.0% and school children, 30.3%. Helminths identified in communities were Schistosoma intercalatum (10.4%), Schistosoma mansoni (4.2%), and a variant of Schistosoma intercalatum (0.2%); Ascaris lumbricodes (6.5%),), Trichuris trichiura (2.5%), hookworm (2.0%) and Taenia spp (0.2%). In school-based, Ascaris lumbricoides had 10.5%, Schistosoma mansoni 8.0 %, Schistosoma intercalatum 5.0% and Strongyloides 1.0% ; Trichuris trichiuria 1.8%, hookworm 1.6%, Taenia species 1.3%. In co-infection, 18.0% prevalence was obtained in the community and 10.5% in schools. The prevalence of malaria parasites in community study was 2742.0%. In a School-based study, the prevalence of malaria disease was 53.0% and 32.1% for first and second school-based study, respectively. Using Polymerase chain reaction (PCR) Plasmodium falciparum was identified at 205 bp and Plasmodium ovale at 787 bp. The mean values, before and after treatment for Eotaxin (5718pg/ml/ 5725pg/ml) and MIP-β (344.1pg/ml/642.6pg/ml) were close and had numerous outlines. The concentration of IFN-γ and IL-4 were higher in all categories of infection than after treatment but with no significant difference. IFN-γ had the highest mean expression (135.6pg/ml) in the coinfection group and least (59.8pg/ml) in the population infected by intestinal helminths only. The value for Plasmodium falciparum was 84.0pg/ml. Similarly, the expression of IL-4 was highest (68.8pg/ml) in co-infection and lowest (40.3 pg/ml) in helminths infected group. The value of IL-4 for those infected by Plasmodium falciparum only was 61.0pg/ml. There In all study groups, IFN-γ and IL-4 were positively correlated before and after treatment; which was significant (r = 0.60) in those infected by P. falciparum only. After treatment, the correlation between IFN-γ and IL-4 was significant in those who were treated for malaria infection (r = 0.7) and those who were treated for co-infection of P. falciparum and helminths (r = 0.6). There was a decrease in values of platelets, White Blood Cells and granulocytes during infection but platelet count was reduced after anthelminthic treatment and increased after anti-malaria administration. The ova of 7 species of helminths were diagnosed in this study. Treatment lowered the concentration of IFN-γ and IL-4 immune molecules in serum, which is of clinical relevance. This study proves that sub-clinical infection brought about a low concentration of IL-4/IFN-γ, altering their counter-inflammatory properties. They rather depended on each other positively. The clinical consequence of IL-4 suppression is the disability in class switch: antibody production is suppressed, resulting in susceptibility to infectious diseases. The presence of P.ovale in co-infection with P. falciparum is significant for the epidemiology and control of malaria disease in the Niger Delta.