Distribution of Plasmodium vivax variants (VK210, VK247 and P. vivax-like) in three endemic areas of the Amazon region of Brazil and their correlation with chloroquine treatment

✍ Scribed by Ricardo L.D Machado; Marinete M Póvoa

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 656 KB
• Volume: 94
• Category: Article
• ISSN: 0035-9203
• DOI: 10.1016/s0035-9203(00)90110-x

✦ Synopsis

The present study evaluated the glass fibre membrane (GFM)-polymerase chain reaction (PCR) -enzymelinked immunosorbent assay (ELISA) technique for genotyping the Plasmodium vivax variants, to verify the distribution of l? vivax variants (VK2 10, VK247 and Z? viva-like) in parts of Brazil and their correlation with levels of parasitaemia, previous malaria experience and clear&e-of parasitaemia linked to different treatment schedules. The samoles were taken from individuals living in Macar& Port0 Velho and Belem. all ofwhich are endemic areas of&ax malaria in the Amazon region of?Brazil. B&d samples were collected on GFMs. The gene that codes for the circumsporozoite proteins of l? vivaxvariants was amplified by PCRand the amplified fragments were hybridized to variant-specific, digoxigenin-labelled oligonucleotide probes by ELISA. The GFM-PCR-ELISA techniaue was shown to be accurate for eoidemiolonical survevs of the vivax complex. All variants were detected & all 3 areas, but only P. vivax VK2i 0 was fo&d as a sin&e agent of infection, while the other 2 occurred as mixed infections. The l? vivax-like variant was found to be associated with low parasitaemia and VK210 with the highest parasitaemia levels; none of the l? vivux variants was linked with a previous malaria experience. In all cases parasitaemia clearance was identical regarding the type of treatment and consequently it is not possible to confirm the previously reported correlation between I? vivax genotype and response to chloroquine.