Another sampling solution is Shitai Transport Medium (VTM), which contains salts, amino acids, vitamins, glucose and protein necessary for virus survival. Sodium phenolate is used as the indicator in the preservation solution. When the pH value of the solution is 6.6-8.0, the solution turns pink. Adding necessary glucose, L- glutamine and protein into the preservation solution can stabilize the protein shell of the virus. It may taste slightly sweet or not sweet (low sweetness of glucose) and slightly umami (including glycine, etc.). ) and salty. Finally, the sampling liquid is forbidden to eat, and it should be washed immediately when it comes into contact with the affected area.