Only the mesophilic C. fetus is normally
invasive. Thermophilic species (optimum 42°C) such as C. jejuni are occasionally invasive. The infections are manifested as meningitis,
pneumonia, miscarriage, and a severe form of Guillain-Barré syndrome (6,20). Thermotolerant strains of C. fetus that grow at 42°C have
been isolated from patients (17).