vaccine-strain measles; hemophagocytic lymphohistiocytosis; vaccine-strain measles/vaccine-strain varicella; Litarature report:  This literature marketed report has been received from the authors of a published article, titled as stated above, and refers to a 19-month-old male was diagnosed with intermediate risk, PRETEXT Ill P+ hepatoblastoma at 14 months of age and treated per AHEP1531 (vincristine/cisplatin/doxorubicin/5-fluorouracil).  On an unknown date, the patient was vaccinated with measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II) subcutaneous injection, unk, administered for prophylaxis (strength, dose, lot #, expiry date, and route of administration were not provided).  On an unknown date, 11 days after receiving measles-mumps-rubella and varicella vaccines the patient treated per AHEP1531 with vincristine, cisplatin, oxorubicin and 5-fluorouracil for intermediate risk, PRETEXT Ill P+ hepatoblastoma. After two cycles of treatment, he developed skin lesions along his scalp, thigh, and groin with vaccine-strain varicella viremia, treated with acyclovir. The subsequent three months of chemotherapy were complicated by fevers and progressive lung infiltrates with no identified etiology. Despite broad anti-infective coverage and chemotherapy being withheld, progression of his nodules led to an extensive evaluation for bacterial, fungal and viral causes. A lung biopsy showed nodular histiocytic infiltrates with reactive multinucleate cells. Polymerase chain reaction testing and histopathology of the sample were negative for tuberculosis, varicella, adenovirus, herpes simplex and cytomegalovirus. Eventually, next-generation sequencing of a bronchoalveolar lavage sample revealed measles, later confirmed as vaccine-strain through the Center for Disease Control. He developed persistent fevers with worsening anemia, thrombocytopenia, coagulopathy, hepatosplenomegaly, and cardiogenic shock. Ferritin was elevated at 39 994 ng/mL and soluble IL-2R was 3544 U/ml. He was diagnosed with hemophagocytic lymphohistiocytosis (HLH) per HLH-2004 criteria. Rapid whole-genome sequencing was negative for primary HLH and other inborn errors of immunity. He began immunosuppressive therapy (dexamethasone and etoposide) for secondary HLH and Emapalumab-lzsg due to poor upfront response. Measles-directed therapy (ribavirin,  IVIG and vitamin A) was initiated once measles was confirmed. Despite these interventions, he succumbed to complications from measles and secondary HLH two weeks after starting HLH-directed therapy.  The reporter considered hemophagocytic lymphohistiocytosis to be related to measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II). The reporter considered vaccine-strain measles to be related to measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II). The reporter considered vaccine-strain measles/vaccine-strain varicella to be related to measles, mumps, and rubella (wistar ra 27-3) virus vaccine, live (M-M-R II).   Upon internal review, the events vaccine-strain measles and hemophagocytic lymphohistiocytosis were determined to be medically significant.  A copy of the published article is attached as further documentation of the patient's experience.  This is one of three cases derived from the same literature article.; Sender's Comments:  US-009507513-2206USA006539: US-009507513-2206USA006540:; Reported Cause(s) of Death: vaccine-strain measles; hemophagocytic lymphohistiocytosis