History of hypersensitivity to any varicella vaccine or measles, mumps, or rubella vaccine, to any of the excipients, or to neomycin, which may be present as trace residues (see Description and Precautions).
Blood dyscrasias, leukaemia, lymphomas of any type, or other malignant neoplasms affecting the haematopoietic and lymphatic system.
Current immunosuppressive therapy (including high doses of corticosteroids) (see Adverse Reactions). ProQuad is not contraindicated in individuals who are receiving topical or low‐dose parenteral corticosteroids (e.g. for asthma prophylaxis or replacement therapy).
Severe humoral or cellular (primary or acquired) immunodeficiency, e.g., severe combined immunodeficiency, agammaglobulinemia and AIDS, or symptomatic HIV infection or an age‐specific CD4+ T‐lymphocyte percentage in children below 12 months: CD4+ <25%; children between 12‐35 months: CD4+ <20%; children between 36‐59 months: CD4+ <15% (see Precautions and Adverse Reactions).
In severely immunocompromised individuals inadvertently vaccinated with measles‐containing vaccine, measles inclusion body encephalitis, pneumonitis, and fatal outcome as a direct consequence of disseminated measles vaccine virus infection have been reported.
Family history of congenital or hereditary immunodeficiency, unless the immune competence of the potential vaccine recipient is demonstrated.
Active untreated tuberculosis. Children under treatment for tuberculosis have not experienced exacerbation of the disease when immunized with live measles virus vaccine. No studies have been reported to date on the effect of measles virus vaccines on children with untreated tuberculosis.
Vaccination should be postponed during any illness with fever >38.5°C.
Pregnancy. Furthermore, pregnancy should be avoided for 1 month following vaccination (see Use in Pregnancy & Lactation).