Rhodococcus equi infection
Rhodococcus equi is a bacterium that lives in dry surface soil of farming and livestock properties. The bacterium is a zoonotic disease and has been known to cause disease in several types of animals including humans. Luckily, human infection remains rare and most reports are of immunocompromised humans (such as those with HIV). R. equi is well recognised in equine veterinary medicine, as it causes pneumonia in foals from 3 weeks to 6 months of age. The disease does not show clinical signs in adult horses or foals older than 6 months unless there is a severe immunodeficiency. The pre-disposing factors for the disease are stress, environmental contamination, and concurrent factors lowering immunity in the foal such as parasitism.