What role does environmental contamination play in the transmission of the disease?
The environment is the most important source of infection. Infected piglets excrete more than 100,000 oocysts per gram of faeces, but can become infected with a low dose of Isospora suis (100 oocysts). The oocysts are highly resistant to external influences, and the environment in the farrowing houses is favourable to rapid sporulation and transmission of the disease. Once Isospora is established on a farm, it is most likely transmitted from one contaminated litter to another.
