Diseases causing pustular moss may be contact-transmissible and autoinoculated infections and are susceptible to prevalence in children. The pathogenic bacteria are mainly Staphylococcus aureus or Streptococcus b haemolyticus that are coagulant plum positive, either alone or in mixed infections. In summer and autumn, high temperature, high humidity, skin impregnation, etc., are easy to make the bacteria invade the skin to reproduce, creating favorable conditions for the development of pus moss. Staphylococcus aureus causes about 50%-70% of the cases, followed by Streptococcus b haemolyticus, and the two can also be mixed infections. Higher temperatures, more sweating and skin maceration are conducive to local bacterial colonization; in patients with pruritic skin disease, itching can break the skin barrier and facilitate bacterial colonization. Diseases causing pustules may be transmitted by close contact or by self-inoculation. Bacteria mainly invade the epidermis and cause purulent inflammation; coagulase-positive phage 2 group 71 Staphylococcus aureus can produce epidermal poikilins, causing toxemia and generalized epidermal relaxation necrosis; in patients with low resistance, bacteria can enter the bloodstream and cause bacteremia or sepsis; in a few patients, nephritis or rheumatic fever can be induced.