{"id":102,"date":"2024-07-22T18:52:35","date_gmt":"2024-07-22T18:52:35","guid":{"rendered":"https:\/\/www.merckvaccines.com\/proquad\/?page_id=102"},"modified":"2026-11-05T10:45:23","modified_gmt":"2026-11-05T10:45:23","slug":"febrile-seizures","status":"publish","type":"page","link":"https:\/\/www.merckvaccines.com\/proquad\/febrile-seizures\/","title":{"rendered":"Febrile seizures"},"content":{"rendered":"\n\n
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ProQuad\u00ae<\/sup> (Measles, Mumps, Rubella and Varicella Virus Vaccine Live) as the 2nd MMRV Dose: Clinical data on febrile seizures<\/strong><\/h1>

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In a large observational study, no febrile seizures occurred after the 2nd dose of ProQuad.<\/strong><\/h2><\/div>\n\n\n\n
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Incidence of febrile seizure with ProQuad vs M-M-R\u00ae<\/sup>II<\/sub><\/span> (Measles, Mumps, and Rubella Virus Vaccine Live) + VARIVAX\u00ae<\/sup> (Varicella Virus Vaccine Live) per 1000 children 12 months to 60 months of age.<\/strong><\/p>\n\n\n\n

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\"Incidence\"Incidence<\/figure><\/div><\/div>\n\n\n\n
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Administration of ProQuad (dose 1) to children 12 to 23 months old who have not been previously vaccinated against measles, mumps, rubella, or varicella, nor had a history of the wild-type infections, is associated with higher rates of fever and febrile seizures at 5 to 12 days after vaccination when compared to children vaccinated with dose 1 of both M-M-R\u00ae<\/sup>II<\/sub><\/span> and VARIVAX administered concomitantly.<\/p>\n\n\n\n

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Study design<\/strong><\/h2><\/div>\n\n\n\n
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Safety was evaluated in an observational study that included 69,237 children aged 12 months to 12 years vaccinated with ProQuad after a 1st dose with M-M-R\u00ae<\/sup>II<\/sub><\/span> + VARIVAX. A historical comparison group included 69,237 age-, gender-, and date-of-vaccination (day and month) matched subjects who were given M-M-R\u00ae<\/sup>II<\/sub><\/span> and VARIVAX concomitantly. The primary objective was to assess the incidence of febrile seizures occurring within various time intervals after vaccination in 12- to 60-month-old children who had neither been vaccinated against measles, mumps, rubella, or varicella, nor had a history of the wild-type infections (N=31,298 vaccinated with ProQuad, including 31,043 who were 12 to 23 months old). The incidence of febrile seizures was also assessed in a historical control group of children who had received their first vaccination with M-M-R\u00ae<\/sup>II<\/sub> and VARIVAX concomitantly (N=31,298, including 31,019 who were 12 to 23 months old). The secondary objective was to assess the general safety of ProQuad in the 30-day period after vaccination in children 12 months to 12 years old.<\/p>\n\n\n\n

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Incidence of febrile seizure with ProQuad vs M-M-R\u00aeII (Measles, Mumps, and Rubella Virus Vaccine Live) + VARIVAX\u00ae (Varicella Virus Vaccine Live) per…<\/p>\n","protected":false},"author":522,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_trash_the_other_posts":false,"editor_notices":[],"footnotes":""},"ga4_page_audience":[],"ga4_page_birn_id":[],"ga4_page_branding":[228],"ga4_page_businessunit":[239],"ga4_page_campaign":[],"ga4_page_content_purpose":[262,1066,1067],"ga4_page_customer_journey_stage":[319],"ga4_page_customer_specialty":[375],"ga4_page_experience":[],"ga4_page_indication":[484],"ga4_page_material_intent":[582],"ga4_page_product":[762],"ga4_page_region":[934],"ga4_page_therapeuticarea":[951],"class_list":["post-102","page","type-page","status-publish"],"yoast_head":"\nIncidence of Febrile Seizures After Second MMRV Vaccine Dose<\/title>\n<meta name=\"description\" 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