Each pathogen causes its own disease. Cholera is caused by bacteria and causes diarrhoea. Tuberculosis (TB) is also caused by bacteria and causes lung damage, because it infects the lungs. Chalara ash dieback is caused by a fungus and causes leaf loss and bark lesions in ash trees.
Malaria is caused by a protist and damages the blood and the liver. HIV is caused by a virus. It destroys white blood cells, and without treatment this can lead to the onset of AIDS.
If you study separate Biology you also need two more. Stomach ulcers are caused by Helicobacter, which is a type of bacteria. Ebola is caused by a virus and causes haemorrhagic fever, which means a high temperature along with severe bleeding.