Genetic characterization of the zoonotic parasite Ancylostoma caninum in the central and eastern USA

Ancylostoma caninum is the most common nematode parasite of dogs in the United States. This study aimed to describe the molecular epidemiology of A. caninum isolates from the central and eastern states of the U.S. using the partial mitochondrial cox1 gene and to compare them with those reported globally. We isolated eggs from fecal samples of dogs and characterized each isolate based on cox1 sequences. A total of 60 samples originating from Kansas, Iowa, New York, Florida, and Massachusetts were included. 25 haplotypes were identified in the U.S. dataset with high haplotype diversity (0.904). Sequence data were compared to sequences from other world regions available in GenBank. Global haplotype analysis demonstrated 35 haplotypes with a haplotype diversity of 0.931. Phylogenetic and network analysis provide evidence for the existence of moderate geographical structuring of A. caninum haplotypes. Our results provide an updated summary of A. caninum haplotypes and data for neutral genetic markers with utility for tracking hookworm populations. Sequences have been deposited in GenBank (ON980650 - ON980674). Further studies of isolates from other regions are essential to understand the genetic diversity of this parasite.