In a manner of speaking, yes. A herx can come on after we think we are clear of that 'threat' as if we are under stress (whether we feel 'stressed' or not), get exposed to a virus (cold/flu) or just over do it physically - or, some herx during the full moon and/or new moon phases - and we did have a full moon yesterday and the new moon is coming up on the 23rd of this month. Some find that they can feel the effects for up to a week before and after.
But for many, it's usually related to starting or raising the dose of something, but as I said above, that's far from the only reason a herx can seemingly come out of nowhere and knock us down. The best thing to do is to keep your detoxing at very good levels, and increase it any time you feel like it's possible that you may be herxing.
Herb only treatment for Lyme & Bart ended 12/11 - no active symptoms for 2 yrs -Herb only treatment for Babesia ended 12/12www.healingwell.com/community/default.aspx?f=30&m=2977364
Had Lyme, Bart, Babs, RMSF, Ehrlichia, Myco, Anaplasmosis, EBV
New Lyme case 8/2014 - Healed 1/31/15 - unknowingly had Asymptomatic Babs and Asymptomatic Bart, being treated now though (2/2016)