When you inoculate children with a polio vaccine, you don't sleep well for two or three months.
Jonas SalkReply when questioned on the safety of the polio vaccine he developed: It is safe, and you can't get safer than safe.
Jonas SalkWhen you inoculate children with a polio vaccine, you don't sleep well for two or three months.
Jonas SalkReply when questioned on the safety of the polio vaccine he developed: It is safe, and you can't get safer than safe.
Jonas Salk