K.S.S.W. v. HHS - DTaP, seizure disorder, encephalopathy, cortical visual impairment, and developmental delays (2023)

Ansel Walters and Shakima Davis-Walters, as natural parents of K.S.S.W., a minor, filed a petition for compensation under the National Vaccine Injury Compensation Program on November 16, 2015. They alleged that the diphtheria, tetanus, acellular pertussis (DTaP) vaccine administered to K.S.S.W. on January 16, 2013, caused him to develop a seizure disorder, encephalopathy, cortical visual impairment, and developmental delays.

K.S.S.W. was born with significant pre-existing conditions, including ventriculomegaly, spina bifida, a tethered spinal cord, and an unbalanced chromosomal translocation (partial trisomy 5p and monosomy 6q), which carried a high risk of neurological abnormalities. His mother also has a similar but balanced chromosomal translocation.

K.S.S.W. underwent surgery for a tethered spinal cord and hydrocephalus shortly after birth. He received his first DTaP vaccine on November 26, 2012, with no reported adverse reaction.

On January 16, 2013, he received his second DTaP vaccine during a pre-surgical evaluation. Four days later, on January 20, 2013, K.S.S.W. was admitted to the hospital for staring episodes, diagnosed with multifocal epilepsy likely related to his underlying brain malformation.

EEG monitoring showed frequent epileptic activity, and he was treated with antiepileptic medications. He was hospitalized twice more in February 2013 for continued seizure activity.

An ophthalmologist suspected neurologic blindness, and K.S.S.W. underwent tethered cord surgery in April 2013. He experienced a prolonged seizure in June 2013.

By September 2013, at one year old, he had global developmental delays, could not sit without support, and could not bear weight on his legs. Doctors informed the parents that K.S.S.W. was unlikely to ever walk or talk.

As of the special master's decision, K.S.S.W. was eight years old and still required assistance with basic care. The special master denied entitlement on April 18, 2023, finding the respondent's experts more persuasive and concluding that the petitioners failed to establish a plausible medical theory of causation, a logical sequence of cause and effect, or a proximate temporal relationship between the vaccine and the alleged injuries.

The special master attributed K.S.S.W.'s conditions to his pre-existing chromosomal abnormalities, which carried a significant risk of seizures. The petitioners sought review of this decision.

The Court of Federal Claims, in a memorandum opinion and order issued August 16, 2023, affirmed the special master's decision. The court found that the special master appropriately weighed the expert testimony, did not abuse her discretion in credibility determinations, and correctly applied the burden of proof.

The court noted that the petitioners' proposed medical theories were unpersuasive and that the respondent's experts provided more credible testimony, aligning better with contemporaneous medical records. The court also found that the special master properly considered K.S.S.W.'s genetic abnormalities as a potential alternative cause for his conditions, as allowed under the Vaccine Act.

The petitioners' motion for review was denied, and judgment was entered for the respondent. Petitioner counsel was Phyllis Widman.

Respondent counsel was Sarah B. Rifkin.

The Special Master's decision was issued by Special Master Christian J. Moran (not named in the court opinion but referenced in the Special Master's decision cited by the court).

The Court opinion was authored by Judge Richard A. Hertling.