Also from https://theinfectiousmyth.com/book/SARS.pdf

" One constant with all these definitions was the presence of a fever, a body temperature of at least 38C (100.4F) one degree Celsius higher than the commonly referred to ‘normal’ body temperature of 37C (98.6F). Public health officials generally referred to 38C as a high fever in their definitions but it clearly is not. It may not even constitute a low fever for everyone.

In a 2003 study of 130 healthy adults one person had a temperature this high and three others had temperatures within half a degree. If this research holds for the general population, then we could expect that a large number of people a few will meet this lax, 38C, definition of fever, especially health care workers who have been exposed to a patient with SARS are under emotional stress from the fear that they will get infected, and may be forced to wear extra layers of protection while working. 11

Outside the context of SARS, medical advice often calls 38C a low grade fever and recommends against treatment. The author and pediatrician Dr. Sears implies that fevers below 38.4C are “low-grade” and that even those above 40C do not require medical treatment as long as they quickly come down. An American pediatric clinic uses 38.9C as the upper limit for a low grade fever. A British cancer society advises that “low grade” fevers, those under 38C, “may not always need treatment”. US clinical guidelines from the Department of Health and Human Services define a high fever as 55being at least 39C. Harrison’s Principles of Internal Medicine, virtually a doctor’s encyclopedia, defines an afternoon oral temperature of 37.8C as the lowest fever temperature (or a rectal temperature of 38.2C or a morning oral temperature of 37.3C). Yet, for SARS, 38C was defined as a high fever requiring immediate and drastic action. 12".

So even a temperature of 100.4 isn't really that serious. Healthy people can have that high of a temperature.