The most common cause of sudden chills and shivering in the elderly is infection, whether bacterial infection, viral infection, fungal cold infection, or other atypical pathogens, such as mycoplasma and chlamydia, will cause the body temperature to shift upward, and then heat dissipation will accelerate, and the clinical manifestation of chills will appear. 2, when the elderly are dehydrated, it will lead to disruption of the neurohumoral environment and endocrine disorders, and then there will be clinical symptoms of chills and shivering. 3.In a non-infectious situation, when the body temperature suddenly rises, there will be chills and shivering. 4.Heatstroke, such as aura heatstroke or severe heatstroke, resulting in heat cramps, heat exhaustion and pyrexia, will also appear chills and shivering. 5.Rare diseases and rare diseases, such as tumors, anemia, hyperthyroidism, will also appear chills and shivering. Sudden chills and shivering may occur.