It's important so that they know exactly where the disease started. Knowing who patient zero is helps them to identify who that person interacted with. From there, they can determine where the disease spread to. This will aid them in stopping the disease before it spreads any further.
Answer:
The toxic chemicals present in the soil can decrease soil fertility and therefore decrease in the soil yield. The contaminated soil is then used to produce fruits and vegetables, which lacks quality nutrients and may contain some poisonous substance to cause serious health problems in people consuming them.
