Doctoral Student / Research Assistant (Volunteer), Department of Veterinary Microbiology and Parasitology, University of Ibadan
Tracking of infection sources of zoonotic protozoan parasites in different water bodies
UNAIDS,(2014) statistics showed that in Nigeria about 3.6million people are infected with HIV/AIDS which is the highest in West Africa and third highest in the world while UNICEF,(2015) statistics revealed that infant mortality in Nigeria is one of the highest in Africa. The need to mitigate the scourge of zoonotic opportunistic pathogens (e.g Cryptosporidium and Giardia) which increases morbidity and mortality in HIV patients and children in Sub-Sahara Africa has stimulated my research focus in investigating all forms of water (Drinking water , recreational water, wastewater and irrigation water) as probable sources infection of these pathogens in children and immunocompromised individuals in Ibadan, southwest Nigeria (the largest city in West Africa) by using single locus and Multi-locus polymorphic genetic markers (18S rRNA, gp60, HSP 70, MSA,MSB, Tpi and giardin genes) in determining the population structure of Cryptosporidium genotypes and subtypes, and Giardia assemblages in different water sources, which will greatly enhance the design of a Possible parasite transmission model for effective prevention and control of these zoonotic devastating diseases which causes chronic intermittent prolong diarrhoea in children and immunocompromised adults .
Abstract: Giardia duodenalis is highly endemic in East Africa but its effects on child health, particularly of submicroscopic infections, i.e., those below the threshold of microscopy, and of genetic subgroups (assemblages), are not well understood. We aimed at addressing these questions and at examining epidemiological characteristics of G. duodenalis in southern highland Rwanda.In 583 children <5 years of age from communities and health facilities, intestinal parasites were assessed by triplicate light microscopy and by PCR assays, and G. duodenalis assemblages were genotyped. Cluster effects of villages were taken into account in statistical analysis. The prevalence of G. duodenalis as detected by microscopy was 19.8% but 60.1% including PCR results. Prevalence differed with residence, increased with age, and was reduced by breastfeeding. In 492 community children without, with submicroscopic and with microscopic infection, underweight (weight-for-age z-score <-2 standard deviations) was observed in 19.7%, 22.1%, and 33.1%, respectively, and clinically assessed severe malnutrition in 4.5%, 9.5%, and 16.7%. Multivariate analysis identified microscopically detectable G. duodenalis infection as an independent predictor of underweight and clinically assessed severe malnutrition. Submicroscopic infection showed respective trends. Overall, G. duodenalis was not associated with gastrointestinal symptoms but assemblages A parasites (proportion, 13%) were increased among children with vomiting and abdominal pain.The prevalence of G. duodenalis in high-endemicity areas may be greatly underestimated by light microscopy, particularly when only single stool samples are analysed. Children with submicroscopic infections show limited overt manifestation, but constitute unrecognized reservoirs of transmission. The predominance of assemblage B in Rwanda may be involved in the seemingly unimposing manifestation of G. duodenalis infection. However, the association with impaired child growth points to its actual relevance. Longitudinal studies considering abundant submicroscopic infections are needed to clarify the actual contribution of G. duodenalis to morbidity in areas of high endemicity.
Pub.: 22 Jun '12, Pinned: 01 Nov '17