Cross Infection of Strongyloides between Humans and Dogs in the Amami Islands, Japan

Abstract

Human strongyloidiasis is a parasitic infection induced by the nematode Strongyloides stercoralis which can cause gastrointestinal disturbances. It is believed to be a zoonosis with a potential for cross infection between humans and dogs. The aim of this work was to study this cross infection. Epidemiological surveys of human intestinal parasites were carried out using direct smears and cultures in the Amami Islands during the summer season from 2003 to 2008. Stools were collected from people and dogs inhabiting the Amami Islands, i.e., Kikai, Amami, Kakeroma, Uke, Yoro and Okinoerabu, Japan. It was confirmed that the infective ratio of Strongyloides was 2.8% of 660 residents studied and 10.0% of their 55 dogs. The owners who had parasite-carrier dogs were not found to have parasites, and, conversely the dogs who were kept by owners having parasites were free of parasites. The epidemiological results of the present study demonstrate that natural infection of Strongyloides does not occur between humans and dogs.

Different but overlapping populations of Strongyloides stercoralis in dogs and humans—Dogs as a possible source for zoonotic strongyloidiasis

“…Nevertheless, our results strongly suggest that there is a considerable risk for dog to human transmission. This would not be in agreement with conclusions by Takano and colleagues [ 62 ] who found that humans in households with Strongyloides -infected dogs were not more likely to be parasitized by S . stercoralis than those with parasite free dogs and concluded that natural transmission does not occur between humans and dogs.…”

Strongyloidesspp. infections of veterinary importance

“…More recently, molecular techniques have shown that there are clear differences between the strains and the existence of subspecies has been proposed (Ramachandran et al 1997;Schär et al 2014). The zoonotic potential of dog S. stercoralis is now being challenged (Takano et al 2009;Schär et al 2014). However, as the studies by Faust and Kagy (1933) demonstrated, S. stercoralis can adapt from a human to dog host, changing its virulence (autoinfection and hyperinfection capabilities) and migratory pathways.…”

Detection of classic and cryptic Strongyloides genotypes by deep amplicon sequencing: A preliminary survey of dog and human specimens collected from remote Australian communities

“…The zoonotic potential of S. stercoralis infected dogs and their potential role in the maintenance of strongyloidiasis transmission has been a topic of interest and discussion for many years (Beknazarova et al, 2017b, Goncalves et al, 2007, Takano et al, 2009). Molecular investigation of human and dog derived S. stercoralis is useful in understanding the nature of cross infection.…”