Dog walking brings Toxocara eggs to people's homes

Abstract

To find out the transmission routes for Toxocara infection, the possibility of transfer of Toxocara eggs from the soil on the paws of animals and on the shoes of people was explored. For this purpose, a study was conducted to find helminth eggs in washings from the paws of dogs after walking, from the shoes of their owners, as well as non-dog owners. Toxocara eggs were detected in 19.4% of the dogs’ paws washings and in 11.4% of washings from the shoes of their owners. The number of eggs found on the paws was about twice as high as on the shoes. The mean number of eggs in the sample was 2.9 in washings from the paws and 1.8 from the shoes. In the samples, Toxocara cati eggs prevailed both in occurrence and in abundance. Out of the total number of positive samples, the eggs of T. cati were found in 83%, and T. canis in 42%. 79% of the found eggs belonged to T. cati and 21% to T. canis. In the washings from shoes of people that do not own dogs, the eggs of parasites were not found. This study demonstrates that the helminth eggs can be transferred from contaminated soil to people’s homes on the paws and shoe soles. Even animals without a patent infection may take part in propagation of infection causing risks of human toxocariasis. In dogs, in addition, the transferred on paws T. canis eggs can serve as a causative agent of permanent, cumulative subclinical infection with a deferred manifestation in posterity. It is supposed that infestation “through the paws” is one of the probable routes of transmission of toxocariasis in dogs.