Open AccessScreening of blood bank samples for the presence of malaria parasites by conventional methods and quantitative nucleic acid sequence‐based amplification (QT‐NASBA) assay
Author(s) -
NOUR BAKRI Y. M.,
MENS PÈTRA F.,
SAEED OSMAN K.,
MOHAMADANI AHMED A.,
SCHALLIG HENK D. F. H.
Publication year - 2007
Publication title -
transfusion alternatives in transfusion medicine
Language(s) - English
Resource type - Journals
eISSN - 1778-428X
pISSN - 1295-9022
DOI - 10.1111/j.1778-428x.2007.00065.x
Subject(s) - parasite hosting , nasba , malaria , plasmodium falciparum , virology , plasmodium vivax , biology , medicine , veterinary medicine , immunology , nucleic acid sequence , biochemistry , dna , world wide web , computer science
SUMMARY The potential of screening blood donations of apparently healthy donors for the presence of malaria parasites with quantitative nucleic acid sequence‐based amplification (QT‐NASBA) technology was assessed. One hundred samples were randomly collected from blood donations at the blood bank of Wad Medani Teaching Hospital (Central Sudan) and analyzed for Plasmodium falciparum contamination by standard microscopy, rapid diagnostic tests (RDTs) and QT‐NASBA (lower detection limit for quantification is 0.1 parasite/µL of blood; absolute lower detection limit < 0.001 parasite/µL). Presence of P. falciparum could not be demonstrated in all samples analyzed by microscopy and RDTs. Eighty out of 100 samples were analyzed by QT‐NASBA. Three samples were lost because of transportation difficulties and 17 gave an insufficient amount of RNA after extraction. Fifty‐five donations were found to be negative for P. falciparum , i.e. < 0.01 parasite/µL of blood, four samples gave a result at the cutoff of the test, i.e. parasite count between > 0.001 and 0.1 parasite/µL. However, 21 of the 80 samples (26.3%) were found to be QT‐NASBA‐positive, i.e. parasites count > 0.1/µL of blood. Mean parasite count of the positive samples was 1.73 parasites/µL (ranging between 0.13 and 18.6 parasites/µL). The present study showed the sensitivity of QT‐NASBA to detect low numbers of P. falciparum in apparently healthy donors.