In recent years, studies have found that rapid temperature fluctuations can be observed by measuring and recording infrared temperature on different fingers even if the patient does not alternate between feeling hot and cold. After the COVID-19 epidemic spread widely in China, a similar result was also found in a COVID-19 patient: the infrared temperature on the ulnar side of the ring finger and the radial side of the little finger appeared to fluctuate with an amplitude greater than 0.5 degrees every minute. At this time, the temperature of other fingers (including the ulnar side of the little finger) fluctuated only slightly or did not fluctuate at all. In addition, as the condition changed, the aforementioned phenomenon disappeared, and the infrared temperature curve on the radial side of the thumb changed slowly and greatly, but the infrared temperature changes in the other fingers were much smaller. These phenomena are difficult to explain in terms of thrombus or changes in blood temperature/flow velocity. In contrast, it may be more reasonable to assume that the heat generated by Qi changes when the flow of Qi is obstructed.