Viruses are economically important because they can cause diseases in plants and animals, which can have significant economic consequences. When a virus infects a plant, it can damage crops and reduce yields, leading to lower profits for farmers. Similarly, when a virus infects an animal, it can cause illness or death, leading to losses for farmers and ranchers. Viruses can also be economically important in a positive way. For example, some viruses can be used to control pests that damage crops, reducing the need for pesticides and saving farmers money. Additionally, viruses can be used in biotechnology to produce vaccines and other medical treatments, which can have significant economic benefits. While viruses do not have cell structures and can only reproduce inside living cells, it is their ability to cause disease in plants and animals that makes them economically important.