Influence of Dextrose and of Low Temperatures on Preservation, Transportation and Viability of Malaria Parasites.

Abstract

In a study of the factors underlying continued growth and reproduction of malaria parasites (Plasmodium vivax) in blood cells removed from the human host, Bass and Johns1 found that the addition of 0.5% of dextrose to human blood before defibrination apparently prevented an endosmosis into the parasitized corpuscles of toxic substances present in normal serum that quickly destroyed the parasites at body or other temperatures. That by the addition of dextrose the parasites continued their asexual reproduction at a rate directly dependent upon the temperature, up to a maximum of 40°C.Confronted with the necessity of preserving and transporting blood containing tertian malaria parasites, I have extended these observations on dextrose content and temperature most conducive to prolonging the viability and consequent infectivity of such parasites.Blood collected from patients presenting the symptoms of therapeutic “inoculation” malaria was first studied daily in stained preparations of defibrinated blood contai...