What causes occasional spike in temperature of a human being?

Occasional spikes in body temperature, or fever, can be caused by various factors, including infections (such as viral or bacterial illnesses), inflammatory conditions, or heat-related illnesses. Other causes may include certain medications, vaccinations, or underlying health issues like autoimmune diseases. The body's immune response typically raises temperature to help combat pathogens. Environmental factors, such as excessive heat or strenuous exercise, can also contribute to temporary increases in body temperature.