How old are the children to be immunized? [originaltext]Tens of thousands of hea

Tens of thousands of health workers will go house to house over the next three days in an effort to immunize 63 million children under the age of five in sub-Saharan Africa. The campaign is the start of monthly national immunization days during the low season for polio. It’s hoped that vaccinating children now--when the virus is at its weakest--will be the best way of stopping transmission.