Soil-Transmitted Helminths in Children in a Remote Aboriginal Community in the Northern Territory: Hookworm is Rare but Strongyloides stercoralis and Trichuris trichiura Persist

Abstract

(1) Background: soil-transmitted helminths are a problem worldwide, largely affecting disadvantaged populations. The little data available indicates high rates of infection in some remote Aboriginal communities in Australia. Studies of helminths were carried out in the same remote community in the Northern Territory in 1994⁻1996 and 2010⁻2011; (2) Methods: fecal samples were collected from children aged <10 years and examined for helminths by direct smear microscopy. In the 2010⁻2011 study, some fecal samples were also analyzed by agar plate culture and PCR for Strongyloides stercoralis DNA. Serological analysis of fingerprick dried blood spots using a S. stercoralis NIE antigen was also conducted; (3) Results and Conclusions: a reduction in fecal samples positive for S. stercoralis, hookworm and Trichuris trichiura was seen between the studies in 1994⁻1996 and 2010⁻2011, likely reflecting public health measures undertaken in the region to reduce intestinal helminths. Comparison of methods to detect S. stercoralis showed that PCR of fecal samples and serological testing of dried blood spots was at least as sensitive as direct smear microscopy and agar plate culture. These methods have advantages for use in remote field studies.

Keywords: Aboriginal; Northern Territory; Rodentolepis nana; Strongyloides stercoralis; Trichuris trichiura; strongyloidiasis.

Figure 1

Identification of S. stercoralis larvae by agar plate culture and formalin sedimentation: (A) Bacterial growth on Mueller-Hinton agar in tracks made by helminth larvae; (B) S. stercoralis adults and filariform larvae in formalin sediment of agar culture; (C) Fungal overgrowth may have obscured larval tracks on some plates.