Persistent infection with Strongyloides venezuelensis in the Mongolian gerbil (Meriones unguiculatus)

Abstract

To examine the fate of Strongyloides venezuelensis , Mongolian gerbils(Meriones unguicalatus ) were orally infected with 1,000 L 3 larvae per animal. Altogether,50 gerbils divided into 5 groups of 10 each were monitored for a period of 570 days todocument the kinetics of faecal egg output, adults worm population, morphologicaldevelopment, fecundity, and hematological changes including peripheral bloodeosinophilia. This study chronicled a life long parasitism of S. venezuelensis in the gerbilhost, and showed that S. venezuelensis infection was quite stable throughout the courseof infection and the worms maintained their normal development as evidenced by theirbody dimension. A progressive loss of body condition of the infected gerbils was observedas the level of infection advanced. However, no detectable pathological changes wereobserved in the gastrointestinal tract. The present findings indicate that animmunocompetent host, such as the Mongolian gerbil, can serve as a life long carriermodel of S. venezuelensis if the worms are not expelled within 570 days after infection.