recrudescence

n. re-eruption, reappearance (disease)

Recrudescence is the reappearance of a disease after it has been quiescent. For example, a clinical attack after parasites in the blood have dropped markedly and the disease has subsided. The parasites. eg. Plasmodium, can persist in the blood without causing apparent symptoms for a few months. It occurs mainly due to suppression of the immune system. This is an important difference between recrudescence and relapse(which occurs due to reactivation of hypnozoites in the liver).
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Recrudescence /re·cru·des·cence/ recurrence of symptoms after temporary abatement.recrudes´cent re·cru·des·cence n. [more]Recrudescence - Community and Resources

Noun
1. a return of something after a period of abatement; "a recrudescence of racism"; "a recrudescence of the symptoms"
(hypernym) outbreak, eruption, irruption
(derivation) break, recrudesce, develop

n. recrudescence, upsurge, fresh outbreak