disease是什么意思？

The team conducted a computer-based analysis to determine the impact a 3-g-per-day reduction in salt intake on rates of heart disease and death.

They also calculated the cost savings emerging from the amount of disease that would be avoided because of lower blood pressure

Cheating can spread like a disease.

Those factors are more than enough to make up for the squalor (肮脏), disease and spectacular poverty that those same migrants must often at first endure when they become urban dwellers.

Hospital workers in at least one case deserted their workplace in panic, thus halting the administering of potentially unclean disease spreading injections, but Ebola has not disappeared.

How do people get infected with the disease according to the speaker