FluMist manufacturing problems in Liverpool, England, stalled efforts to get the nasal vaccine spray approved for children ages 1 to 4.

Gaithersburg?s MedImmune released information Tuesday about the Food and Drug Administration?s inspection of its Liverpool manufacturing facility. The FDA wrote a warning letter to inform the company that problems with contamination have not been properly addressed and that the company?s application to expand the age range for the vaccine will not proceed until these issues are resolved.