Answer:
I think this statement is expressing the idea that being safe and taking precautions can help prevent accidents, which can be thought of as a type of disease in the sense that they can cause harm or suffering. For example, if someone is driving a car and they follow all the rules of the road and take precautions such as wearing a seatbelt and not texting while driving, they are less likely to be involved in a car accident. In this sense, practicing safety could be seen as a "vaccine" against the "disease" of accidents.
This idea can be applied to many other areas as well. For example, if someone is working with hazardous chemicals in a laboratory, following proper safety procedures and wearing protective gear can help prevent accidents or injuries. Similarly, if someone is participating in a sport, wearing the appropriate safety equipment (such as a helmet or padding) can help reduce the risk of accidents and injuries.
Overall, the concept of safety is an important one, as it can help prevent accidents and reduce the risk of harm or injury to individuals.