Although frequently reported in the literature, a staff varicella policy is not standard in many hospitals even in developed countries. In the present study, we assessed varicella zoster immunity in staff from two neonatal units from hospitals in São Paulo, Brazil. Ninety-seven percent of all staff working in both units agreed to participate. A simple and cost-effective varicella policy was subsequently set up, based on costs and data from serology and a history of previous varicella infection. Our results confirm that a varicella vaccination programme can be implemented in a healthcare facility, even in developing countries.