What is a vaccine vial monitor?
Vaccine vial monitor is a thermo – sensitive device applied on any vaccine mainly OPV vial. At an unsafe cumulative exposure to> 80C, it changes its color. It has a circle within a square. If the circle is lighter than square it means it is a good vaccine. When the circle becomes of the same color shade or darker than the square, it means it’s unsafe to use the vaccine & it should be discarded.
