Albert Sabin and prove its extraordinary effectiveness and safety. The Sabin vaccine worked in the intestines to block the poliovirus from entering the bloodstream. In the intestines, Sabin had discovered, the poliovirus multiplied and attacked. Thus, the oral vaccine broke the chain of transmission of the virus and allowed for the possibility that polio might one day be eradicated. Between 1955 and 1961, the oral vaccine was tested on at least 100 million people in the USSR, parts of Eastern Europe, Singapore, Mexico, and the Netherlands. The first industrial production and mass use of oral poliovirus vaccine (OPV) from Sabin strains was
A Little Frog Is looking for His Father no a father. Then The Little Frog says to The Little Grasshopper, "Do not cry. I'll be Your Dad..." A Little Frog Is looking for His Father A Little Frog Is looking for His Father () is The 1964 Soviet Russian Stop-motion Animation Film by Roman Kachanov. This Film produced by Soyuzmultfilm studio. The Little Frog looking for, but can not find a dad, who can protect him and play with him. He meets a various animals and asks them to become his dad. All these animals are larger than The Little Frog. An animals do not want to become