The Public Health Agency of Canada has good news for kids between the ages of three and nine, and their parents. The agency says healthy children over three probably won’t need a second pediatric dose of H1N1 vaccine, as was previously recommended.

But the agency is reserving the right to change the policy later if newer scientific data points to a need for two doses for these children.

The agency says toddlers from six months to just under three years will need two shots, given at least 21 days apart. Children between three and nine with chronic health conditions should get a first shot as soon as possible, then get a second later, with an interval of at least three weeks.