Συμβολή της γονοτύπησης στη διερεύνηση περιστατικών ελονοσίας από Plasmodium vivax

Abstract

Epidemiological studies carried out in endemic and non-endemic areas for malaria around the world are considered imperative from a public health point of view. Investigation for transmission of malaria to humans remains the ultimate goal, through the action of the five currently described different species of Plasmodium. The present study attempted to further investigate and characterize the genotypic profile of malaria P. vivax cases. A total of 22 positive samples were used and the contribution of genotypic analysis was evaluated. These samples were sent to the Malaria Reference Center of the Department of Parasitology, Entomology and Tropical Diseases of the former National School of Public Health (currently Department of Public Health Policies, School of Public Health, University of Western Attica), taken from people descending from endemic countries who reside in the Peloponnese region. The samples examinated were related to 14 cases for the year 2016 and eight cases for the year 2015, respectively. Genotypic analysis of positive P. vivax samples was carried out in the laboratory using a targeted polymerase chain reaction molecular protocol. More specifically, a nested PCR approach was implemented, according to which a defined area of the Msp3a gene of P. vivax was amplified. The latter constitutes a highly polymorphic antigen-encoding gene of the surface protein 3a of plasmodium merozoites, often used in studies of genetic diversity of plasmodium isolates. The proposed methodology consists of two successive PCR reactions, using different pairs of primers for each reaction (P1-P2 & N1-N2) and aims to increase the sensitivity of the final reaction product. The extracted results showed the identification of three distinct genotypes of P. vivax in all tested samples (A, B, C). The majority of samples were categorized as having genotype A. Furthermore, implementation of genotypic analysis in the investigation of malaria cases from P. vivax was highlighted, a notion which should be extended towards studying additional genetic regions and contributing substantially in terms of epidemiological correlation of clinical cases.