for example pneumococcal pneumonia cause(etiology): pneumococcus condition: cold. tired pulmonary tuberculosis cause: tubercular bacillus condition: worry, malnutrition Ill. pathogenesis of disease It studies how the etiology can cause the disease in the bodyfor example pneumococcal pneumonia cause(etiology): pneumococcus condition: cold, tired pulmonary tuberculosis cause: tubercular bacillus condition: worry, malnutrition Ⅲ. pathogenesis of disease It studies how the etiology can cause the disease in the body