In the United States Court of Federal Claims 

FOR PUBLICATION 

No. 16-1494V 

(Filed: March 13, 2023) 

 

EBONIE WEAVER, 

parent of T.M., a minor,

 Petitioner, 

v. 

SECRETARY OF HEALTH 

AND HUMAN SERVICES,

Respondent. 

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Vaccine Act, 42 U.S.C. § 300aa-10 et seq.; 

Off-Table Causation-in-Fact & 

Significant Aggravation Claims; 

Complex Febrile Seizure; 

Abnormal Screenings; Epilepsy 

Edward Kraus, Kraus Law Group, LLC, Chicago, IL, for plaintiff. 

Meghan R. Murphy, Torts Branch, Civil Division, U.S. Department of Justice, 

Washington, DC, for defendant, with whom on the briefs were Brian M. Boynton, 

Principal Deputy Assistant Attorney General, C. Salvatore D’Alessio, Director, 

Heather L. Pearlman, Deputy Director, and Lara A. Englund, Assistant Director, 

Torts Branch, Civil Division, U.S. Department of Justice, Washington, DC. 

OPINION AND ORDER 

BONILLA, Judge.

 Petitioner Ebonie Weaver, parent of a minor child identified herein as T.M., 

seeks review of a decision of the United States Court of Federal Claims Office of 

Special Masters (OSM) denying entitlement under the National Childhood Vaccine 

Injury Act, 42 U.S.C. § 300aa-10 et seq. Ms. Weaver claims a vaccine-induced 

complex febrile seizure caused T.M. to develop a chronic seizure disorder and, 

concomitantly, significantly aggravated T.M.’s preexisting developmental delay. 

 This decision was initially filed under seal on February 24, 2023, in accordance with Rule 18(b) 

of the Vaccine Rules of the United States Court of Federal Claims, to allow the parties to propose 

redactions based upon privacy concerns. No proposed redactions were filed. 
2 

For the reasons set forth below, the Court finds the Chief Special Master improperly 

elevated petitioner’s burden of proof by requiring contemporaneous medical 

screening evidence documenting brain injury under a “seizures beget seizures” 

theory of causation. The legal error further extended to petitioner’s significant 

aggravation claim. Accordingly, Ms. Weaver’s motion is GRANTED, the decision 

of the OSM is REVERSED-IN-PART and VACATED-IN-PART, and this matter is 

REMANDED for further proceedings consistent with this opinion. 

BACKGROUND 

I. Medical History 

T.M. was born on March 29, 2013. No complications were reported during 

delivery (at 391⁄2 weeks) and her Apgar scores for appearance (skin color), pulse 

(heart rate), grimace (reflexes), activity (muscle tone), and respiration (breathing 

rate and effort) totaled 9 out of 10 after one minute and, again, after five minutes.1 

T.M. was discharged from the hospital on March 31, 2013. During her April 3, 2013 

follow-up wellness visit, healthcare providers found five-day-old T.M. to be in 

good health. 

On July 15, 2013, during her four-month wellness visit, T.M. received the 

following vaccines: diphtheria, tetanus, and acellular pertussis (DTaP) (1st dose); 

haemophilus influenzae type b (Hib) (1st dose); hepatitis B (HepB) (2nd dose); 

inactivated poliovirus (IPV) (1st dose); rotavirus (RV) (1st dose); and pneumococcal 

conjugate (PVC) (1st dose). During T.M.’s physical examination, the healthcare 

provider checked the “well child” box under “Assessment” on the medical form 

but noted “Developmental Delay.” See ECF 7-4 at 8. When asked about T.M.’s 

developmental progress using the Ages and Stages Questionnaires® (ASQ),2

Ms. Weaver reported T.M. was not meeting the following milestones: pushing up 

to elbows, symmetrical movement, and rolling and reaching for objects. The 

healthcare provider documented their impression as “ASQ – Delay but is not 

4 mo[nth]s yet.” See ECF 7-4 at 8. 

1 See JOHNS HOPKINS ALL CHILDREN’S HOSPITAL, https://www.hopkinsallchildrens.org/PatientsFamilies/Health-Library/HealthDocNew/What-Is-the-Apgar-Score (last visited Feb. 22, 2023) 

(“A baby who scores a 7 or above on the test is considered in good health. . . . Ten is the highest score 

possible, but few babies get it. That’s because most babies’ hands and feet remain blue until they 

have warmed up.”). 

2 The Ages and Stages Questionnaires® are a screening tool used to measure developmental progress 

in children between the ages of one month and five years. See AGES AND STAGES QUESTIONNAIRES, 

https://agesandstages.com/products-pricing/asq3/ (last visited Feb. 22, 2023). 
3 

On December 6 and 10, 2013, nine-month-old T.M. returned for her 

six-month wellness visit.3 During the December 10, 2013 visit, Ms. Weaver 

reported T.M. “was doing everything normal until 4 months and now she is 

not doing much.” See ECF 7-8 at 4; see also ECF 11-1 at 70. Documenting 

developmental milestones, the healthcare provider noted T.M. occasionally meets 

9 of the 16 milestones, is “babbling – little” and “smiles at mom,” but she does not 

sit alone, roll from front to back or vice versa, pass a toy from hand to hand, 

imitate beginning consonant sounds, or say “mama” or “dada.” ECF 7-8 at 4. The 

healthcare provider referred T.M. to a developmental clinic for further evaluation 

and early intervention treatment. During the December 10, 2013 wellness visit, 

T.M. received the following vaccines: HepB (3rd dose); DTaP (2nd dose); Hib 

(2nd dose); IPV (2nd dose); PVC (2nd dose); and RV (2nd dose). ECF 7-8 at 6. 

That evening, T.M. developed a fever which Ms. Weaver treated with Tylenol. 

On December 11, 2013 at approximately 2:00 a.m.–less than 24 hours after 

receiving the vaccines–T.M. was taken by ambulance to the emergency room and 

treated for a complex febrile seizure lasting 35 minutes. Ms. Weaver reported the 

following symptoms to the paramedics and hospital staff: grunting, body shakes, 

clenched hands, curled toes, pulsating limbs, heavy drooling, and eyes rolled 

upward.4 When examined at 4:00 a.m., T.M. presented with fever and shaking and 

“seizure-like activity.” See ECF 11-1 at 8. Showing signs of respiratory distress, 

T.M. was intubated and placed on a ventilator. T.M.’s bloodwork showed an 

abnormally high white blood cell count; a flu panel, Computed Tomography 

(CT or CAT) brain scan, and chest x-ray yielded negative results. T.M. was given 

antibiotics and transferred to another hospital for treatment in the facility’s 

pediatric intensive care unit. Following her hospital transfer, T.M.’s fever broke 

and she was extubated with no further seizure activity. An electroencephalogram 

(EEG) of T.M.’s brain activity performed that afternoon was interpreted to be 

normal. During evening rounds, a treating physician documented the likely 

diagnosis as complex febrile seizure. T.M. was discharged the following day. 

Six days later, on December 18, 2013, T.M. returned to the emergency room 

after experiencing three episodes of vomiting and diarrhea, but no reported fever 

or additional seizures. By this time, Ms. Weaver had filed a Vaccine Adverse Event 

Reporting System (VAERS) report suggesting a link between T.M.’s febrile seizure 

3 The December 10, 2013 follow-up visit was necessary after healthcare providers were unable to 

verify T.M.’s vaccine history on December 6, 2013; consequently, no vaccines could be administered 

during the initial check-up. 

4 T.M.’s father also reported that T.M.’s tongue was swollen and confirmed the excess drooling. 
4 

and her recent vaccinations.5 T.M. was prescribed a nausea medication, instructed 

to stay hydrated, and discharged. During a January 14, 2014 wellness visit, 

the treating physician documented their assessment of T.M.’s December 11, 2013 

episode as a “DTaP induced versus febrile seizure.” See ECF 7-4 at 5. 

On March 18, 2014, T.M. returned to the emergency room after suffering a 

second febrile seizure and remained hospitalized overnight for observation. Medical 

staff flagged T.M.’s “significant developmental delay” and urged Ms. Weaver to seek 

early intervention for T.M. through prescribed physical and occupational therapy. 

See ECF 7-7 at 241; accord id. at 239–40. In early April 2014, healthcare providers 

continued to raise concerns that T.M. was not meeting developmental milestones. 

On May 1, 2014, T.M. suffered a third febrile seizure while at daycare and 

again transported by ambulance to the emergency room. According to her daycare 

provider, T.M. “began to shake, foam at the mouth, and her eyes rolled into the back 

of her head while [the teacher] was holding her.” See ECF 7-1 at 2. Prior to her 

discharge later that day, T.M.’s body temperature measured 102.2 degrees. Over 

the following week, T.M. was evaluated by the Illinois Bureau of Early Intervention 

and a pediatric neurologist. She was diagnosed as suffering from “[e]pileptic 

seizures, [f]ebrile seizures, [s]taring spell, and [d]evelopmental delay.” See ECF 7-2 

at 10. T.M. was prescribed a low dose of the anti-epileptic drug Keppra. 

During a May 13, 2014 wellness visit, Ms. Weaver reluctantly authorized 

the administration of three more vaccines: measles, mumps, and rubella (MMR) 

(1st dose); varicella/chickenpox (1st dose); and hepatitis A (HepA) (1st dose). 

Two months later, on July 3, 2014, T.M. underwent a two-hour EEG. The results 

were found “within normal limits and appropriate for [the] patient[’s] age”; 

however, the entry under “[a]bnormalities” reads: “slow wave activity was present 

throughout the recording and was unresponsive to stimulation.” ECF 7-2 at 43. 

Through the fall of 2014, T.M.’s overall development showed few signs of 

improvement. During a September 4, 2014 wellness visit, 17-month-old T.M. 

did not meet any of the 11 evaluated developmental milestones.6 Concerned the 

vaccinations were causing or contributing to T.M.’s continuing health issues, 

Ms. Weaver declined to authorize additional scheduled vaccinations for T.M. 

5 Co-managed by the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug 

Administration (FDA), VAERS “is a national early warning system to detect possible safety problems 

in U.S.-licensed vaccines.” See VAERS, https://vaers.hhs.gov/about.html (last visited Feb. 22, 2023). 

6 Although T.M. was reportedly “rolling more frequently” and “up on her knees,” she was not yet 

crawling. See ECF 7-3 at 71. Moreover, the healthcare provider checked “no” for the following 

developmental milestones: vocabulary 3 to 6+ words; listens to story; points to one or more body 

parts; gestures what they want; understands simple commands; walks, stoops, climbs stairs; 

stacks blocks; feeds self with fingers; drinks from a cup; looks for fallen objects; and social play. Id. 
5 

On December 30, 2014, T.M. suffered a breakthrough seizure and returned to 

the emergency room. The seizure reportedly “last[ed] for about ten minutes [and] 

then resolved on its own.” See ECF 7-9 at 5. Hospital staff attributed the episode 

to T.M. missing her morning dose of Keppra. By the time T.M. was examined by a 

doctor two hours after her arrival at the hospital, she had returned to her baseline 

and discharged. T.M.’s development showed no documented signs of improvement 

throughout 2015 and into 2016. 

On May 8, 2016, T.M. experienced an active afebrile seizure and was taken 

to the emergency room. Medical staff attributed the episode to T.M.’s reported 

congestion, exposure to viral illness, and a missed Keppra dose. A continuous-video 

EEG identified the following abnormalities: absent posterior dominant rhythm 

(PDR); excessive beta activity; and diffuse slowing. The EEG report further noted: 

“EEG is consistent with a global encephalopathy and drug-induced fast activity.”7 

See ECF 9-4 at 62. An August 16-17, 2016 follow-up ambulatory (24-hour) EEG 

revealed the following abnormalities: “regional epileptiform discharges involving 

the posterior quadrant maximal over midline parieto-occipital region.” Id. at 293-

94. The results were deemed “consistent with an active epileptogenic source in the 

midline parieto-occipital region [of the brain].” Id. 

Since then, T.M. has experienced several afebrile seizures resulting 

in additional trips to the emergency room and, in at least one instance, being 

admitted to the hospital. In diagnosing T.M., healthcare providers generally offer 

non-vaccine related explanations (e.g., recurrent ear infections, missed Keppra 

doses, exploring alternative treatments). Her current diagnoses include epilepsy 

and global encephalopathy (i.e., global developmental delay). Nearing her 

10th birthday, T.M.’s global and profound developmental delays continue. 

She remains nonverbal, wears diapers, and continues to experience seizures. 

II. Petition and OSM Decision 

Ms. Weaver’s petition presents a causation claim and significant aggravation 

claim, asserting the December 10, 2013 vaccines administered to T.M. caused her 

seizure disorder and significantly worsened her developmental delays. In support 

of her causation claim, Ms. Weaver relies upon the “seizures beget seizures” theory, 

asserting that T.M.s’ initial vaccine-induced febrile seizure lowered her seizure 

threshold, paving the way for her chronic seizure disorder. The resulting brain 

damage from the attributable seizures, Ms. Weaver continues, significantly 

aggravated T.M.’s preexisting developmental delays. 

7 “Encephalopathy is a term for any disease of the brain that alters brain function or structure.” See 

NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKE, https://www.ninds.nih.gov/healthinformation/disorders/encephalopathy#:~:text=Encephalopathy%20is%20a%20term%20for,increased

%20pressure%20in%20the%20skull (last visited Feb. 22, 2023). Although the parties dispute the 

import of this diagnosis, the OSM decision under review makes no mention of the May 8, 2016 EEG. 
6 

On September 23, 2022, the OSM issued a decision denying entitlement. The 

Chief Special Master found the December 10, 2013 vaccinations were responsible 

for T.M.’s ensuing fever and at least contributed to her initial febrile seizure. Citing 

the “absence of evidence that [T.M.’s] brain was likely damaged by the first febrile 

seizure,” however, the Chief Special Master concluded T.M.’s subsequent seizures 

were not likely attributable to the first. Weaver v. Sec’y of Health & Hum. Servs., 

No. 16-1494V, 2022 WL 12542485, at *1 (Fed. Cl. Spec. Mstr. Sept. 23, 2022). 

The Chief Special Master also held Ms. Weaver failed to establish that T.M.’s 

preexisting developmental delays were significantly aggravated by her initial 

vaccine-induced febrile seizure. 

DISCUSSION 

 

I. Standard of Review 

In reviewing a Vaccine Act decision, this Court may 

(A) uphold the findings of fact and conclusions of law of the 

special master and sustain the special master’s decision, 

(B) set aside any findings of fact or conclusion of law of the 

special master found to be arbitrary, capricious, an abuse of 

discretion, or otherwise not in accordance with law and issue 

its own findings of fact and conclusions of law, or 

(C) remand the petition to the special master for further action 

in accordance with the court’s direction. 

42 U.S.C. § 300aa-12(e)(2). The Federal Circuit clarified the applicable standards of 

review as follows: findings of fact are reviewed under the arbitrary and capricious 

standard; discretionary rulings are reviewed under an abuse of discretion standard; 

and legal conclusions are reviewed de novo under the “not in accordance with law” 

standard. Turner v. Sec’y of Health & Hum. Servs., 268 F.3d 1334, 1337 (Fed. Cir. 

2001) (citing Munn v. Sec’y of Health & Hum. Servs., 970 F.2d 863, 870 n.10 

(Fed. Cir. 1992)). 

II. Causation-In-Fact 

To prove causation-in-fact for an injury not listed in the Vaccine Injury Table, 

42 U.S.C. § 300aa–14(a) (“off-Table injury”), a petitioner must demonstrate by 

preponderant evidence: 
7 

(1) a medical theory causally connecting the vaccination and the injury; 

(2) a logical sequence of cause and effect showing that the vaccination 

was the reason for the injury; and (3) a showing of a proximate 

temporal relationship between vaccination and injury. 

Althen v. Sec’y of Health & Hum. Servs., 418 F.3d 1274, 1278 (Fed. Cir. 2005). To 

satisfy this burden, a petitioner need not prove their claim to a medical or scientific 

certainty; rather, they must simply show that it is “more likely than not” that the 

vaccine caused the injury. Moberly v. Sec’y of Health & Hum. Servs., 592 F.3d 1315, 

1322 (Fed. Cir. 2010). 

The three Althen prongs comprise an overlapping analysis determining 

whether a vaccine more likely than not caused injury. Capizzano v. Sec’y of Health 

& Hum. Servs., 440 F.3d 1317, 1326 (Fed. Cir. 2006) (“[T]he statute requires only 

that the claimant show that it is more likely than not that this claimant’s [injury] 

was caused by the vaccine.”) (emphasis in original). Under the first prong, 

petitioner must provide a reputable medical or scientific explanation for their 

theory of causal connection. Boatmon v. Sec’y of Health & Hum. Servs., 941 F.3d 

1351, 1359 (Fed. Cir. 2009) (quoting Moberly, 592 F.3d at 1322). To satisfy the 

second prong, petitioner must show how the facts of their case align with the 

medical theory presented and demonstrate a logical connection between the vaccine 

and the injury (i.e., a logical sequence of cause and effect). See Capizzano, 440 F.3d 

at 1326 (“[M]edical records and medical opinion testimony are favored in vaccine 

cases, as treating physicians are likely to be in the best position to determine 

whether ‘a logical sequence of cause and effect show[s] that the vaccination was 

the reason for the injury.’”) (quoting Althen, 418 F.3d at 1280) (citing 42 U.S.C. 

§ 300aa–13(a)(1)). Finally, the third prong requires petitioner to show the injury 

occurred within the expected time frame of the proposed medical theory. See 

de Bazan v. Sec’y of Health & Hum. Servs., 539 F.3d 1347, 1352 (Fed. Cir. 2008). 

 

In this case, the Chief Special Master found Ms. Weaver satisfied Althen

prongs one and three. In addressing prong one, the Chief Special Master found 

that Ms. Weaver provided a credible medical theory demonstrating how vaccines 

can cause a febrile seizure and, in turn, how a febrile seizure can cause a chronic 

seizure disorder. See Weaver, 2022 WL 12542485, at *25 (“I can easily determine 

herein that almost any vaccine, alone or grouped with others, could cause sufficient 

inflammation to trigger a single febrile seizure.”) (emphasis in original); id. at *27 

(“I emphasize again—the contention that a vaccine-caused febrile seizure could 

constitute the first ‘domino’ in a chronic seizure disorder is scientifically reliable.”) 

(emphasis in original). Regarding prong three, the Chief Special Master credited 

testimony demonstrating the requisite timing between T.M.’s vaccination and her 

complex febrile seizure. See id. at *12 (“Finally, Dr. Huq addressed the timeframe 

between T.M.’s vaccinations and her first seizure, deeming it consistent with the 

short interval for initial inflammatory changes (which could occur within 24 hours 

to a few days after vaccination).”). Neither of these conclusions are contested here. 
8 

Accordingly, the Court focuses on the determination that Ms. Weaver did not satisfy 

the second Althen prong. 

A. Contemporaneous Evidence of Brain Injury 

The Chief Special Master improperly elevated Ms. Weaver’s burden of proof 

under Althen prong two. In denying compensation, the Chief Special Master 

focused on the absence of abnormal screening results evidencing brain injury 

contemporaneous with T.M.’s first febrile seizure, finding: 

[T]he medical record in this case does not support the conclusion that 

T.M.’s December 2013 post-vaccination febrile seizure caused her 

epilepsy. 

Specifically, the record does not establish that the initial febrile seizure 

harmed T.M.’s brain sufficiently to conclude that it likely “explains” 

what transpired thereafter. On the contrary, persistent testing 

performed over the next two-plus years, whether in the form of EEGs 

or [magnetic resonance imaging (MRIs)], did not confirm the presence 

of a seizure-induced brain malformation or injury that could then 

(under a “seizures beget seizures” theory) be deemed causal of all 

subsequent seizures. 

See Weaver, 2022 WL 12542485, at *25 (emphasis in original) (citing three EEGs, 

an MRI, and a CT scan yielding normal results between December 2013 and 

May 2016). The Chief Special Master noted that it was not until August 2016 that 

epileptiform activity in T.M.’s brain was corroborated by an EEG yielding abnormal 

results. Id. Upon these findings, the Chief Special Master concluded T.M.’s first 

vaccine-induced seizure could not be deemed responsible for her epilepsy “in the 

absence of record evidence corroborating the presence of brain injury that could 

credibly be attributed to the vaccine-induced febrile seizure.” Id. at *27. 

 Requiring abnormal screening results to substantiate T.M.’s initial 

brain injury contradicts the spirit of the Vaccine Act and the standard to which 

petitioners are held. The preponderance of the evidence standard applicable 

under the Act does not require medical certainty. Rather, causation is determined 

on a case-by-case basis with “no hard and fast per se scientific or medical rules.” 

Knudsen v. Sec’y of Health & Hum. Servs., 35 F.3d 543, 548 (Fed. Cir. 1994). 

Moreover, under the National Vaccine Injury Program, close calls regarding 

causation are resolved in favor of injured claimants. Althen, 418 F.3d at 1280. The 

question whether T.M.’s brain was harmed by her initial vaccine-induced complex 

febrile seizure, leading to her chronic seizure disorder, is a close call and, as such, 

must be resolved in Ms. Weaver’s favor. 
9 

Under the scientifically sound theory that a vaccine-caused complex febrile 

seizure could serve as the proverbial “first domino” to topple culminating in T.M.’s 

development of a chronic seizure disorder, the second Althen prong required 

Ms. Weaver to produce only a measure of reliable evidence that her brain was more 

likely than not harmed by the initial seizure. While a concurrent abnormal EEG or 

other medical screening may provide such evidence, the absence of an abnormal 

screening alone is not determinative. 

The Federal Circuit has rejected the requirement that a petitioner satisfy the 

second Althen prong by presenting specific medical evidence or scientific proof to 

establish a logical sequence of cause and effect, concluding that such a requirement 

“impermissibly raises a claimant’s burden under the Vaccine Act.” See Capizzano, 

440 F.3d at 1325–26. The court highlighted the inherent value of opinions from 

treating physicians and medical experts. See id. at 1325. Relevant circumstantial 

evidence may satisfy the preponderance standard. Id. In this case, T.M.’s treating 

physicians and medical expert opined that T.M.’s regression evidences the impact of 

her initial vaccine-induced seizure (and subsequent seizures) on her development. 

In contrast, expert witness testimony regarding the probative value of the initial 

EEGs and other screening tests were, at best, inconclusive. 

1. Treating Physicians 

“[Medical opinion] testimony is ‘quite probative’ since ‘treating physicians 

are likely to be in the best position to determine whether a logical sequence of cause 

and effect show[s] that the vaccination was the reason for the injury.’” Andreu v. 

Sec’y of Health & Hum. Servs., 569 F.3d 1367, 1375 (Fed. Cir. 2009) (quoting 

Capizzano, 440 F.3d at 1326) (additional citations omitted). Indeed, “in certain 

cases, a petitioner can prove a logical sequence of cause and effect between a 

vaccination and the injury (Althen prong two) with a physician’s opinion to that 

effect where the petitioner has proved that the vaccination can cause the injury 

(Althen prong one) and that the vaccination and injury have a close temporal 

proximity (Althen prong three).” Moriarty v. Sec’y of Health & Hum. Servs., 

844 F.3d 1322, 1333 (Fed. Cir. 2016) (citing Capizzano, 440 F.3d at 1326). 

Under Ms. Weaver’s scientifically reliable seizures beget seizures theory 

of causation, children who experience febrile seizures–particularly complex 

febrile seizures–are more likely to develop seizure disorders, including epilepsy. 

The proffered theory is sufficiently borne out by the circumstantial evidence 

presented. The causal link between T.M.’s December 10, 2013 vaccinations and 

her initial complex febrile seizure within 24 hours is well documented in T.M.’s 

contemporaneous emergency room records. Further, the medical opinions of 

T.M.’s pediatric neurologist connected T.M.’s initial febrile seizure and her currently 

diagnosed seizure disorder. Contemporaneous medical records prepared by other 

healthcare professionals further document T.M.’s developmental regression and 
10 

substantiate a causal connection between T.M.’s initial febrile seizure and her 

current diagnosis. 

In the days and months following T.M.’s third febrile seizure over the course 

of five months, pediatric neurology specialist Lubov Romantseva, MD, noted T.M.’s 

developmental plateaus and regressions occurred contemporaneously with T.M.’s 

vaccinations and the onset of her febrile seizures. See, e.g., ECF 7-2 at 15, 16, 76. 

To this point, the frequency of T.M.’s febrile seizures and the possible impact of the 

antiseizure medication prescribed immediately following T.M.’s third febrile seizure 

proves corroborative. Prior to taking a daily dose of Keppra, T.M. suffered febrile 

seizures on December 11, 2013, March 18, 2014, and May 1, 2014. Her subsequent 

December 30, 2014, and May 8, 2016 febrile seizures occurred on days when T.M. 

did not take her medication. Dr. Romantseva continues to treat T.M. and, based on 

the record presented, her opinions supply substantiated evidence of causation. See 

Mondello v. Sec’y of Health & Hum. Servs., 132 Fed. Cl. 316, 323 (2017) (“Medical 

records ‘warrant consideration as trustworthy evidence’ because these records 

are ‘generally contemporaneous to medical events,’ and ‘accuracy has an extra 

premium.’”) (citing Cucuras v. Sec’y of Health & Hum. Servs., 993 F.2d 1525, 1528 

(Fed. Cir. 1993)). 

 

T.M.’s developmental evaluations timeline further supports the conclusion 

that T.M. experienced developmental regression as a result of her vaccine-induced 

December 11, 2013 complex febrile seizure and subsequent febrile seizures. At her 

December 10, 2013 wellness visit–during which T.M. received the vaccine regimen 

at issue–she was reported to meet some (but not all) developmental milestones. 

See ECF 7-8 at 4. During a 12-month wellness visit conducted on April 8, 2014–

one month after T.M. suffered a second febrile seizure in three months–Lester 

Hockenberry, MD, documented that T.M. met only 1 of 13 developmental 

milestones. See ECF 7-3 at 85–86. By September 4, 2014, Dr. Hockenberry 

reported that T.M. did not meet a single developmental milestone. See ECF 7-3 

at 71. The Court finds the contemporaneous medical opinions regarding T.M.’s 

developmental regression probative in determining T.M. suffered a brain injury 

after her first vaccine-induced febrile seizure. 

Relevant here, the Chief Special Master seemingly conflated T.M.’s 

pre-seizure developmental concerns with her post-seizure developmental regression. 

See Weaver, 2022 WL 12542485, at *26 (“The fact that T.M.’s seizures occurred in 

the context of established developmental concerns also weighs against a conclusion 

that her first seizure caused what followed.”). As expert witnesses for both parties 

explained, there is a significant difference between developmental delay and 

regression. Pediatric Neurologist John Zempel, MD, for example, distinguished 

between the “many kids who have development delay,” and the “uncommon” 

phenomenon of regression, which requires immediate evaluation and treatment by 

a neurologist. See ECF 72 at 251. In turn, Pediatric Neurologist Ahm M. Huq, MD, 
11 

explained that a loss of once-mastered skills is “unusual” and, in the absence of 

evidence of illness or degenerative condition, is compelling evidence of harm to the 

brain. Id. at 105–06. Dr. Huq further noted the adverse impact brain seizures 

can have on child development, particularly during their early years of critical 

development. See id. at 107. 

Notwithstanding the negative screenings cited by the Chief Special Master, 

discussed infra, the Court finds sufficient evidence in the record to support 

Ms. Weaver’s contentions that T.M.’s December 11, 2013 vaccine-induced complex 

febrile seizure made her more susceptible to future seizures and that indications 

of a lowered seizure threshold were partially masked by the prescribed antiseizure 

medication. The Court notes the plausibility of this explanation for why T.M.’s 

allegedly lower seizure threshold did not result in significantly more seizures: it 

would strain credulity to suggest it is merely coincidental that on the two reported 

days T.M. missed a Keppra dosage, she suffered additional seizures. T.M.’s ensuing 

developmental regression further evidences the brain damage she suffered. 

In reaching these conclusions, the Court finds several similar OSM decisions 

instructive. See, e.g., Silverio v. Sec’y of Health & Hum. Servs., No. 15-235V, 

2019 WL 6694020 (Fed. Cl. Spec. Mstr. Nov. 14. 2019) (complex febrile seizure 

triggered propensity for additional seizures; Althen prong two satisfied by treating 

physician’s testimony despite normal EEG, MRI, and CT scans; first abnormal 

reading occurred two years after initial complex febrile seizure using a continuous 

EEG); Fuller v. Sec’y of Health & Hum. Servs., No. 15-1470V, 2019 WL 7576382 

(Fed. Cl. Spec. Mstr. Dec. 17, 2019) (complex febrile seizure increased risk of 

developing epilepsy under seizures beget seizures theory; Althen prong two satisfied 

in part by expert testimony; first conclusively abnormal EEG was conducted 

three years after the initial seizure); Ginn v. Sec’y of Health & Hum. Servs., 

No. 16-1466V, 2021 WL 1558342 (Fed. Cl. Spec. Mstr. Mar. 26, 2021) (considering 

normal MRI results as evidence ruling out alternative causes under Althen prong 

two, but not ruling out vaccinations as the potential cause). Put simply, requiring 

contemporaneous abnormal screening evidence to prove brain injury under a 

“seizures beget seizures” theory of causation improperly elevates a petitioner’s 

burden under the second Althen prong. 

2. EEGs and Other Screenings 

As noted in the Chief Special Master’s decision, medical experts for both 

parties testified to the limitations of EEGs and other screening tests in detecting 

brain injury or abnormality. See, e.g., ECF 72 at 250 (Dr. Zempel: “If you have 

epileptiform abnormalities, that makes it more likely that you have a diagnosis of 

epilepsy. A normal EEG does not rule out that you have epilepsy.”); id. at 44–45, 

148–49 (Dr. Huq: “a short-term EEG has a 30 percent chance of capturing the 

abnormal. A long-term EEG usually have [sic] 60 percent, 60 or 70 percent. So a 
12 

positive EEG is helpful, and negative EEG cannot rule out the diagnosis. It’s always 

a clinical diagnosis.”). Moreover, in reviewing T.M.’s abnormal August 2016 EEG 

results, Dr. Zempel reiterated: 

I think that this is the first time we’ve seen evidence of epileptiform 

activity on an EEG. Again, I think that means it’s more likely in the 

future that there could be recurrent unprovoked seizures, but there 

are children out there who have these abnormalities and don’t have 

epilepsy, and there are children who have epilepsy and don’t have 

any abnormalities. 

Id. at 255 (emphasis added). Regarding T.M.’s normal screening results during 

the first two years following her initial complex febrile seizure, Dr. Huq opined on 

their limited import because “[t]here are patients who have seizures every day and 

can have normal EEG[s].” Id. at 148–49. As noted above, Dr. Huq explained that 

the short-term EEGs performed in the two years following T.M.’s initial complex 

febrile seizure have only a 30 percent chance “of capturing the abnormal[,]” whereas 

long-term EEGs–like the one performed in May 2016 (and August 2016)–capture 

abnormalities in 60 to 70 percent of individuals. Id. at 143, 148–49. Overall, 

both experts agreed that T.M.’s abnormal August 2016 EEG was consistent with 

epilepsy, and Dr. Huq, in particular, opined that her multiple EEGs (including 

those that were normal) were consistent with this diagnosis. 

 With respect to MRIs, Dr. Huq explained they would not likely detect 

molecular changes in the brain that occur after status epilepticus or a complex 

febrile seizure, and that the molecular changes might not be detectable for years. 

See id. at 93. In turn, although highlighting an MRI’s ability to detect prolonged 

seizures and significant brain injuries, Dr. Zempel declined to opine that an MRI 

would detect all injuries in 100% of cases. See ECF 73 at 7–8. As for CT scans, 

Dr. Zempel testified he was “much less confident that a significant injury would 

appear on CT scan.” Id. at 6. 

 Consistent with the Federal Circuit’s decision in Capizzano, the nature 

and extent of the Chief Special Master’s reliance upon EEG and other screening 

evidence was in error. See 440 F.3d at 1325–28. While abnormal screening results 

may be probative, the law does not require abnormal screening results to prove a 

particular injury under the Vaccine Act. 

 

B. Burden to Eliminate Alternative Causes 

To the extent the Chief Special Master assigned Ms. Weaver the burden of 

eliminating alternative independent potential causes for T.M.’s injury as part of 

her prima facie causation claim, the burden shift constitutes legal error. Under the 

Vaccine Act, once a petitioner has met their burden on causation, the burden shifts 
13 

to the Secretary to establish by a preponderance of the evidence that the injury or 

harm was unrelated to the vaccine. See Walther v. Sec’y of Health & Hum. Servs., 

485 F.3d 1146, 1151 (Fed. Cir. 2007) (citations omitted). As stated by this Court: 

The Act only requires a showing of “but for” causation and that the 

vaccine was a “substantial factor,” not that the vaccine was the only 

cause. Thus the coincidence of another potential causal agent is 

not fatal to a claim under the Act. If petitioner meets its burden on 

causation, then it is the government’s burden to prove that some other 

cause is to blame, not petitioner’s to disprove it. 

Mondello, 132 Fed. Cl. at 325. 

Importantly, while evidence of other possible sources of injury can be relevant 

in the causation analysis, the Federal Circuit has clarified: 

first, that a special master may not require the petitioner to shoulder 

the burden of eliminating all possible alternative causes in order 

establish a prima facie case[;] and second, that a special master may 

find that a factor other than a vaccine caused the injury in question 

only if that finding is supported by a preponderance of the evidence. 

Stone v. Sec’y of Health & Hum. Servs., 676 F.3d 1373, 1380 (Fed. Cir. 2012) 

(internal citations omitted).8 

8 The Secretary seeks to apply the holding in Stone to this case. Readily distinguishable from this 

case, in Stone, the special master concluded that the children’s SCN1A gene mutation was the 

sole cause of their severe myoclonic epilepsy of infancy (SMEI) (also known as Dravet syndrome), 

and that the petitioners failed to establish the existence of any brain damage. See 676 F.3d at 1375, 

1377–78, 1385. In affirming the OSM’s decision, the Federal Circuit held: “[t]he special master did 

not reject the petitioners’ evidence of brain damage on the ground that it was circumstantial; rather, 

he found that [the expert’s] inference of brain damage, in the face of clinical records showing no 

brain damage, was unpersuasive and that it was therefore insufficient to carry the petitioners’ 

burden on causation.” Id. at 1385. It is also worth noting that in Stone, unlike here, the burden of 

proof shifted to the respondent to demonstrate by a preponderance of the evidence that the gene 

mutation “was ‘more likely than not the “but for” and “substantial factor” that caused’ the SMEI in 

both children.” Id. at 1377 (citations omitted). 

 Here, it is undisputed–and confirmed by both parties’ experts–that T.M.’s August 2016 

EEG was abnormal, demonstrated global encephalopathy, and is consistent with T.M.’s epilepsy 

diagnosis. Compare ECF 9-4 at 293–94 and ECF 72 at 145–46, 254–55 with Stone, 676 F.3d at 

1382 n.2, 1385 (finding EEG evidence “questionable”; petitioner’s expert witness unpersuasive). 

Additionally, the Court finds T.M.’s medical records—particularly the medical opinions of her 

pediatric neurologist and contemporaneous developmental assessments—amply support the 

conclusion that T.M. experienced developmental regression, which is probative circumstantial 

evidence of brain injury in this case. 
14 

In this case, rather than hold the Secretary to their shifted burden of proof, 

the Chief Special Master faulted Ms. Weaver for not refuting or otherwise 

addressing the notion that T.M.’s developmental delay could have caused or 

increased her risk or propensity for seizures. See Weaver, 2022 WL 12542485, at 

*26 (“Although I do not purport to find that T.M.’s developmental issues explain her 

subsequent seizure activity and epilepsy, Petitioner did not persuasively rebut this 

kind of evidence, and it therefore further diminishes the possibility that the initial 

febrile seizure alone explained why T.M. continued to experience seizures 

afterward.”) (emphasis added); id. (“[T]he record in this case paints a picture of a 

child likely susceptible to seizure activity generally, but whose course could not be 

deemed inevitable once the first febrile seizure occurred. T.M.’s initial febrile 

seizure was likely vaccine-caused—but that seizure in turn was not the cause of 

what followed.”) (emphasis in original). The law is clear: Ms. Weaver is not 

required to prove that T.M.’s initial vaccine-induced complex febrile seizure was the 

sole or predominant cause of her epilepsy. See Shyface v. Sec’y of Health & Hum. 

Servs., 165 F.3d 1344, 1352–53 (Fed. Cir. 1999) (petitioners must demonstrate 

vaccine was a but-for cause of and a substantial factor in the resulting injury; 

petitioners are not required to establish the vaccine was the only or predominate 

cause of the injury). 

III. Significant Aggravation 

Under the Vaccine Act, claimants may seek compensation for preexisting 

injuries that were “significantly aggravated” by vaccination. 42 U.S.C. § 300aa11(c)(1)(C)(i-ii). To prove an off-Table significant aggravation claim, petitioners 

must satisfy the six-prong test adopted in Loving v. Sec’y of Health & Hum. Servs., 

86 Fed. Cl. 135, 143–44 (2009). Under the Loving framework, a petitioner must 

establish by a preponderance of the evidence: 

(1) the person’s condition prior to administration of the vaccine, (2) the 

person’s current condition (or the condition following the vaccination 

if that is also pertinent), (3) whether the person’s current condition 

constitutes a “significant aggravation” of the person’s condition 

prior to vaccination, (4) a medical theory causally connecting such 

a significantly worsened condition to the vaccination, (5) a logical 

sequence of cause and effect showing that the vaccination was the 

reason for the significant aggravation, and (6) a showing of a 

proximate temporal relationship between the vaccination and the 

significant aggravation. 

Id. at 144. Here, Ms. Weaver argues T.M.’s vaccine-induced complex febrile seizure 

and resulting seizure disorder exacerbated her preexisting developmental delay. 
15 

In addressing the significant aggravation claim, the Chief Special Master 

found that T.M.’s contemporaneously documented pre-vaccine developmental issues 

“literally worsened” and became “more pronounced” in the months and years after 

she was vaccinated, thereby satisfying the first three Loving factors. See Weaver, 

2022 WL 12542485, at *27 & n.21 (emphasis in original). Turning to the fourth 

factor, the Chief Special Master “assum[ed] that a vaccine-induced febrile seizure 

could cause sufficient brain injury to worsen preexisting developmental issues.”9 

See id. at *27. 

In assessing the fifth Loving factor, the Chief Special Master relied upon his 

findings under the second Althen prong, concluding that T.M.’s initial vaccineinduced complex febrile seizure was similarly not “the source of worsening” for her 

developmental delay. See Weaver, 2022 WL 12542485, at *27. The Chief Special 

Master explained: “My finding with respect to a lack of sufficient ‘did cause’ proof 

that the first, vaccine-caused febrile seizure T.M. experienced was causal of her 

overall epilepsy also bears on Petitioner’s claim that her pre-existing developmental 

delays were exacerbated by the December 2013 vaccinations.” See id.; accord id. at 

*28 (“[T]he initial, undoubtedly vaccine-related febrile seizure has not been shown 

to be the ‘linchpin’ to what followed.”). Given the Court’s conclusion reversing the 

causation determination under Althen prong two, the extension of the erroneous 

finding in analyzing the Loving factors necessitates a reevaluation on remand.10

CONCLUSION 

For the foregoing reasons, Petitioner’s Motion for Review (ECF 83) is 

GRANTED, the Decision Denying Entitlement issued by the Office of Special 

Masters (ECF 77 & 81) is REVERSED-IN-PART and VACATED-IN-PART, 

and this case is REMANDED for further proceedings consistent with this opinion. 

It is so ORDERED. 

 

 

 ___________________ 

 Armando O. Bonilla 

Judge 

9 The assumption is presumably based on the Chief Special Master’s findings regarding Althen

prong one (i.e., the counterpart to the third Loving factor). 

10 On remand, the Chief Special Master must also address the sixth Loving factor (i.e., proximate 

temporal relationship between the vaccination and the significant aggravation)–the counterpart 

to the third Althen prong–as his initial decision is silent on that issue. The Court declines to make 

these factual findings in the first instance on petitioner’s motion for review. See, e.g., Mondello, 

132 Fed. Cl. at 325.