What are the immediate and contributory causes of diseases? Explain it with them diarrhoea

What are the immediate and contributory causes of diseases? Explain it with the example of a child suffering from diarrhoea.
Answer:
Immediate cause of a disease is the primary factor causing a disease. Contributory causes are factors, which do not cause the disease themselves but provide conditions for the disease to occur. Virus causing diarrhoea is the immediate cause. Contaminated drinking water and lack of resistance due to under-nourishment are the contributory causes.