Health officials are still searching for answers about a hepatitis outbreak that has affected children.

Sometimes it's easy to forget how common many diseases were before vaccines for them were introduced. When the disease is not around, people may not notice as much.

Getting your flu shot — and nine other common vaccines — just became a bit more convenient. No need to hassle with a doctor appointment. Just drop by Walmart.

While some vaccines can be given once and offer protection for life, others require booster shots and still may wear off over time.