Answer: four criteria to establish a causative relationship between a microbe and a diseases
Explanation:
1- "Bacteria must be present in every case of diseases"
2- "Bacteria must be isolated from the host with the diseases and grown in pure culture"
3- "The specific diseases must be reproduced when a pure culture of bacteria is inoculated into a healthy susceptible host"
4-"Bacteria must be recovered from the experimentally infected host"
