K.G. v. Hhs, 951 F.3d 1374

Oct 2011: K.G. received an influenza vaccine before bilateral knee replacement; began experiencing neuropathic symptoms (numbness, tingling) by early 2012.
From late 2012–2016 K.G. suffered significant mental decline (hospitalizations, alcoholism, Korsakoff’s amnesia); admitted May 2013 and a court appointed her sister as guardian and conservator in March 2014.
K.G. improved in mid-2016; guardianship terminated Aug 2016. She retained counsel in late 2017 and filed a Vaccine Act petition in Jan 2018.
Special Master found onset mid-Feb 2012, concluded equitable tolling did not survive the 2014 guardianship appointment (clock restarted), and dismissed as untimely; the Court of Federal Claims affirmed.
Federal Circuit vacated and remanded: held equitable tolling for mental incapacity is available under the Vaccine Act and that appointment of a guardian is not a per se bar — courts must evaluate guardianship as one factor in the equitable-tolling/diligence analysis.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Availability of equitable tolling for mental incapacity under the Vaccine Act	Mental incapacity should toll the 36-month limitation	Equitable tolling based on mental incapacity is not available under the Act	Tolling for mental incapacity is available (rebuttable presumption applies)
Effect of appointment of a legal guardian on tolling	Guardianship does not automatically end tolling; circumstances may prevent guardian from filing	Guardianship vests authority to sue; appointment removes the extraordinary circumstance	Guardianship is a factor— not a per se rule— courts must assess if it eliminated the extraordinary impediment
Proper standard for diligence	Diligence must be judged during the period of incapacity and include guardian’s efforts	Petitioner and/or representative were not diligent before and after incapacity	Diligence inquiry should focus on the period of extraordinary circumstance and consider guardian’s characteristics and conduct
Remedial disposition	Vacate and remand to consider all relevant facts under proper standard	Affirmation of Special Master decision	Court vacated and remanded for reconsideration under the announced framework

Menominee Indian Tribe v. United States, 136 S. Ct. 750 (elements of equitable tolling require diligence and an extraordinary circumstance)
Cloer v. Sec'y of Health & Human Servs., 654 F.3d 1322 (Vaccine Act claims may be equitably tolled)
Barrett v. Principi, 363 F.3d 1316 (mental illness can justify equitable tolling)
Checo v. Shinseki, 748 F.3d 1373 (diligence need only be shown during the extraordinary circumstance)
Irwin v. Dep't of Veterans Affairs, 498 U.S. 89 (rebuttable presumption that equitable tolling is available in suits against the government)