Brief Answer:
this is high enough but this is not enough information

Detailed Answer:
Hello,

the temperature is not the sole determinant of the severity of an infection. Other symptoms or findings may be more important. For example any level of fever with serious headache and nuchal rigidity is very important because it may signify meningitis. Other important sings and symptoms (the list is not exhaustive) may include:
- shortness of breath
- pleuritic chest pain (pain when taking deep breaths)
- flank pain
- abdominal pain
- faintness (low blood pressure)
- confusion or other nervous system symptoms

If he only has fever and malaise then the most likely cause is a viral infection (like influenza for example). In any case it's better if a doctor evaluates his condition but if this is too difficult for you then you should definitely consider visiting the emergency room if any of the aforementioned symptoms or signs occur.

Symptoms and signs that may be reassuring (but not 100% safe in all cases) include:
- runny nose
- sore throat with enlarged tonsils and white patches
- recent contact with persons with diagnosed viral illnesses

I hope you find my comments helpful!
Kind Regards!

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Brief Answer:
the level of fever is not very important

Detailed Answer:
The level of fever is not very important. Influenza may present with fever as high as 104.5F or even higher. I could say (but this is not evidence based - it's just my opinion based on my personal experience) that a fever higher than 105F is high enough to warrant immediate investigation as it's usually related to bacterial infections. The rest of the symptoms or signs I've mentioned in my first answer are far more important...

Best wishes for a speedy recovery!

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Brief Answer:
You're welcome

Detailed Answer:
You're welcome, glad to help!

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