What are the consequences of not changing sheets for a long time?

What are the consequences of not changing sheets for a long time? When I look at this question, I feel numb and uncomfortable all over. First of all, if nothing else, the smell alone makes people uncomfortable, and winter is better. If it is summer, bacteria and mites multiply particularly fast. If you have skin diseases, you should change the sheets and wash the quilt frequently, at most once every half month, otherwise you can't stand it. If women have gynecological diseases, besides paying attention to personal hygiene, the cleanliness of sheets and bedding is also very important. If it is not cleaned up in time, the rapid reproduction of germs will lead to the deterioration of the disease and even unimaginable consequences.