Parents in the US could use address data to seek influenza immunization for children between the ages of six months and 18 years.
The Center for Disease Control (CDC) has advised parents to get their children vaccinated to protect them against influenza and also in a bid to prevent the spread of swine flu.
Parents unsure of where they can go to get the vaccination have the option of entering their address data at FluClinicData.org to access information on nearby doctors.
Anne Schuchat MD, director of the CDC's National Center for Immunization and Respiratory Diseases, said: "This past year's recommendations encouraged vaccination and the plan has been that this year this would be a full recommendation - no longer just an encouragement or 'where feasible', but a full-out recommendation."
Children are a major element in disease transmission and the CDC is keen to tackle this through immunization.
Swine flu originated in Mexico but has spread around the world over the last few months.