Procedure when vaccination is unsuccessful

When it is ascertained that the vaccination or re-vaccination has been unsuccessful, the child shall be caused by the guardian to be vaccinated again forthwith, if so desired by the vaccinator and subsequently inspected as aforesaid: Provided that where the vaccination or re-vaccination has been unsuccessful on three consecutive occasions, the child shall be considered to have natural immunity from small-pox and shall be exempted from vaccination thereafter.

Provided that where the vaccination or re-vaccination has been unsuccessful on three consecutive occasions, the child shall be considered to have natural immunity from small-pox and shall be exempted from vaccination thereafter.