This case was reported by a physician via call center representative and described the occurrence of blurred vision in a 12-year-old female patient who received BOOSTRIX. On 14th August 2017, the patient received BOOSTRIX .5 ml. On 15th September 2017, 32 days after receiving BOOSTRIX, the patient experienced blurred vision (serious criteria disability), myopia (serious criteria disability), creatine phosphokinase increased (serious criteria disability) and feeling unwell. On 16th September 2017, the patient experienced walking difficulty (serious criteria disability), increased reflexes (serious criteria disability), myalgia of lower extremities (serious criteria disability), lower extremities weakness of (serious criteria disability), dizziness (serious criteria disability) and unable to walk. On an unknown date, the patient experienced paresthesia (serious criteria disability) and numbness (serious criteria disability). The patient was treated with Ear Drops {NOS} and TYLENOL. On an unknown date, the outcome of the blurred vision, walking difficulty, increased reflexes, paresthesia, numbness, myalgia of lower extremities, lower extremities weakness of, dizziness and unable to walk were not recovered/not resolved and the outcome of the myopia was unchanged and the outcome of the creatine phosphokinase increased and feeling unwell were unknown. The reporter considered the blurred vision, walking difficulty, increased reflexes, myopia, creatine phosphokinase increased, paresthesia, numbness, myalgia of lower extremities, lower extremities weakness of and dizziness to be possibly related to BOOSTRIX. It was unknown if the reporter considered the unable to walk and feeling unwell to be related to BOOSTRIX. Additional details were reported as follows: The physician was a pediatrician who did not work at the location where the vaccine was administered to the patient, who said that the nurse practitioner was responsible for the vaccine's administration at the clinic where the vaccine was administered. The patient's concomitant medication included ear drops starting from 14th August 2017. The reporter described that the patient's vision changed as being blurred vision but that was a subjective symptom because the pediatric eye examination was normal. On 15th September 2017, 32 days after vaccination, the patient was not feeling well, blood creatine phosphokinase increased and had myopia. The leg muscle pain was described as occurring in both legs with leg weakness in both legs. The difficulty in ambulating was described as the patient being unable to walk for more than a few steps. The dizziness occurred in the evening on the same day as the leg muscle pain with weakness and ambulation difficulty, which had occurred in the morning. On 16th September 2017, 33 days after vaccination, the patient experienced ambulation difficulty, mildly brisk reflexes, leg muscle pain and weakness, dizziness and unable to walk. On 16th September 2017 and 12th October 2017, the patient went to the emergency room because of the symptoms but was not admitted. The medical workup for this patient now included an ophthalmologist visit in which she was diagnosed with myopia and nothing else. The recent Blood creatine phosphokinase test results were pending. The patient recently started having numbness, tingling, and paresthesias which had been waxing and waning day to day. Less than a year after vaccination the patient experienced paresthesias, tingling, and numbness. On 13th October 2017, the patient was seen by a neurologist and the exam results were inconclusive, excepting diagnosis of mildly brisk reflex. On 13th October 2017, the patient had a normal cardiology workup. The patient had a pending Electroencephalography. The patient's parents were distraught and the reporter said these symptoms had been disabling that she had not been able to go back to school and was still unable to walk on her own most of the time. All of the symptoms were still waxing and waning from day to day. The reporter said the myopia could just be a baseline physical finding and was unsure if it was related to all of the other symptoms. The reporter gave permission to be contacted by GCSP. The reporter had no specific dosing details for the vaccine beyond what was documented already above.