My son has had a fever of 104 for 5 days now.  He has also been vomitting and doesnt want to eat.  I noticed today that his gums are very red and swollen (he goes to his dentist for regular checkups every 6 mos).  I took him to the dr. on friday and she said it was a virus.  She gave him a perscription for his nausea and an antibiotic, but said to hold off on the antibiotic b/c it would not get rid of the virus.  He has been very tired too.
Thanks for your query, I have gone through your query. The fever and vomiting could be because of the viral infection or food poisoning. Take your son to the physician and get the infection cleared. After that we can treat the red and swollen gums. The redness and swelling of gums can also occur along with viral infection(herpes). Or it can be because of the deposits. Get your sons teeth cleaned. Let him do saline gargling. I hope my answer will help you. Take care.