Ovicidal activity of chemical disinfectants and the nematophagous fungus duddingtonia flagrans on eggs of the geohelminth toxocara canis

Abstract

Toxocara canis is a zoonotic canine geohelminth that contaminate the environment with eggs which later hatch the larvae that can infect human beings. Its environmental control is a challenge and require studies focused on establishing efficient strategies for reducing the risks for public health. Thus, this study aimed to evaluate the in vitro ovicidal efficacy of two commercially disinfectants used singly, combined, or in association with the nematophagous fungus Duddingtonia flagrans (AC001) against T. canis eggs. For this purpose, seven groups were created as follow: G1 (AC001), G2 (sodium hypochlorite 2%), G3 (benzalkonium chloride 15%), G4 (AC001 + sodium hypochlorite 2%), G5 (AC001 + benzalkonium chloride 15%), G6 (sodium hypochlorite 2% + benzalkonium chloride 15%), and G7 (water - control group). There were statistically significant differences (p < 0.05) between the treated and control groups, and the egg reductions were G1 (48.2%), G2 (100%), G3 (60.9%), G4 (100%), G5 (26.9%), and G6 (100%). The use of disinfectants alone or combined among them was more effective in destroying eggs than D. flagrans. In conclusion, sodium hypochlorite 2% and benzalkonium chloride 15% were effective for destructing T. canis eggs in vitro, while D. flagrans had a moderate ovicidal action. However, the application of this fungus is promising to be used as a biological and safety strategy for decontaminating the environments where leisure activities occur and exist risks for public health.