Wondering if there might be any medics on here that can advise on what this might be.
My husband is late thirties and a runner. He's vegan and lives an incredibly healthy lifestyle. He has the resting pulse rate of an athlete and I've rarely known him to get unwell in the 12 years I've known him.
Since the summer of 2020 he's been experiencing fevers sporadically. He's had two this month. They usually last for about 24 hours and sometimes he vomits. He shivers and complains his whole body aches. A day later it passes and he's fine again. Until the next one. His temperature is usually around 39.4 during these episodes.
Initially in 2020 we suspected Lyme disease as we live in an area where it's prevalent and DH frequently gets bitten by ticks while out trail running, although he always removes them immediately when he arrives home (gross I know!). A GP reluctantly prescribed a course of doxycycline in 2020 to treat potential Lyme disease. DH couldn't tolerate it from what I remember (joint pain side effect) and so they switched him to another antibiotic.
He's done multiple PCRs during these fevers since 2020 and all negative. As far as we know neither of us have ever had covid, which is somewhat surprising as I work in a frontline role.
Does anyone have any ideas about what might be causing this? The GP didn't seem particularly concerned when my husband told them about it recently but something is telling me this isn't normal. He never had fevers as an adult until two years ago.
Should we do private testing for Lyme? Or push the GP for blood tests? Any advice would be appreciated