some body temperatures of humans are lower than 37 degrees. For me for example is a temperature of 36 degrees normal so i have a fever with 37 degrees. Maybe its common in Japan to have lower body temperatures.
When my temperature becomes 37°C it means I have a fever, too.
I think japanese people has a lower body temperatures.
Normal temperature of body is 36.6 degrees. If you have 37-38 degrees then it's called subfebrile state. Above 38 is slight fever. But it's all conventionally and its may be different for everyone. Maybe they have other termology?
* terminology
I saw that a lot in manga : people have fever with 37 degrees... but isn't it totally normal? like the temperature of human body is 37 degrees, no? I don't have a fever until I reach 38 degrees...