By MIKE STOBBE – 14 hours ago
ATLANTA (AP) — Children suffered higher rates of fever-related convulsions when they got a Merck & Co. combination vaccine instead of two separate shots, according to a new study presented Wednesday.
The results prompted a federal advisory panel on vaccines to water down their preference for the combo vaccine ProQuad, which protects against measles, mumps and rubella as well as chickenpox.
In the study of children ages 12 months through 23 months, the rate of seizures was twice as high in toddlers who got ProQuad, compared with those who got one shot for chickenpox and one for the three other diseases.
The risk translates to about one extra case of convulsion for every 2,000 doses of ProQuad given said Dr. Nicola Klein, who lead the federally funded study. She presented the data at a meeting of the Advisory Committee on Immunization Practices.
The study focused on children who develop fevers and then go into convulsions — an occurrence that frightens parents but usually has no lingering consequences. There were no deaths in the new study.
ProQuad was licensed in 2005. It's been in extremely short supply since last year, when Merck suspended production because of manufacturing problems. The company expects to resume ProQuad production next year.
ProQuad costs $124 per dose, about the same as the two other shots combined.