As described in the package insert, the standard dosing schedule of the OCV is two doses with the second dose given 2 weeks after the first. In several campaigns, it was felt to appropriate to give a single dose to twice as many people and to give the second dose at a later time when this was logistically possible. In fact, modelling of the impact of OCV during an outbreak finds that when the vaccine supply is limited (as it is currently), more cases are prevented if a single dose strategy is used since a single dose can be provided to twice as many people. Even if the efficacy is a bit lower, the number of cases prevented will be higher. Even the individual person in this situation will be better off if more of his neighbors also receive vaccine since he benefits from the herd protection when more people are vaccinated.