Observations on parastrongyliasis in two land snails Achatina achatina and Achatina marginata with special reference to public health

Between December 2001 and August 2002, a study on the prevalence of Parastrongylus cantonensis nematode infection in two edible land snails Achatina marginata and Achatina achatina were carried out in Owerri, Imo State, Nigeria. Of the 350 A. marginata examined, 209 (59.7%) were infected with a mean worm load of 27.2 larvae per snail. Similarly, 221 (61.1%) of 362 A. achatina examined had larvae of P. cantonensis with an intensity of 38.1 larvae per snail. The prevalence of Parastrongyliasis increased significantly with snail size (age) in both snails. There were seasonal fluctuations of infection intensities in both snails with peak intensities occurring during the rainy season, 43.9 larvae per snail in July and 55.8 larvae per snail in August for A. marginata and A. achatina respectively. The involvement of P. cantonensis in some diseases of man is highlighted. Keywords: Parastrongylus cantonensis; Achatina achatina; Achatina marginata; snail; public health; NigeriaAnimal Production Research Advances Vol. 2 (3) 2006: pp 183-188