At the initial stage of hand, foot, and mouth disease, children may experience symptoms such as fever, coughing, runny nose, and drooling, which are similar to those of an upper respiratory infection. Some children may also experience nausea and vomiting. Subsequently, oval or spindle-shaped blisters appear on the hands, feet, and even the back. These blisters are surrounded by a red halo, and the fluid inside the blisters is clear. The long axis of the blister aligns with the skin lines. Then, the centers of the blisters turn yellow, become concave, dry out, and begin to peel. Additionally, there are scattered, fairly hard, pale red papules or vesicles at the fingertips, and similar lesions can also appear in the mouth, such as on the lips, tongue, oral mucosa, and gums. However, the oral blisters quickly rupture, forming gray-white spots or a gray-white film surrounded by a red halo. Underneath the gray-white film, punctate or patchy erosive surfaces can be seen. These symptoms are generally quite obvious, and it is recommended to seek medical treatment promptly if observed.