Trust, learning, and vaccination: a case study of a North Indian village.

For US 17 dollars a child can be immunized against six major illnesses. Even at this price, a country such as India would have to spend half its health budget on providing vaccinations. Given the wide variation in immunization costs it may be possible to decrease this cost to more sustainable levels, but to do so we need to arrive at a more thorough understanding of factors affecting household demand for vaccination. Using data on vaccination and pre-natal care collected by the authors in the Garhwal region of India, we explore one aspect of the demand for vaccination in some detail. We show that informational constraints play an important role in the household decision to seek vaccination, and moreover, that learning about the efficacy of vaccinations only through empirical observation may be hard even in environments with variation in vaccination and the high incidence of vaccine-preventable diseases. We argue that when learning about vaccination is inefficient, households use concurrent interventions with easily observable outcomes to evaluate the veracity of a provider's claim regarding preventive care. Hence, the success of immunization programs becomes crucially linked to the success of parallel programs by the same provider.