The tuberculin test, also known as the PPD test, costs around$50-100 and can be done at the local CDC or some hospitals, and the cost is not fixed. The cost may also vary from region to region depending on the reagents used. For PPD, after the injection, do not scratch the local area and do not wash with soap and water, and generally observe the results after 72 hours. Generally, if it is negative, you need to get BCG vaccination. If the result is positive or strongly positive, BCG vaccination is not needed, but it is also necessary to pay attention to exclude the possibility of infection with tuberculosis bacteria.