Giovanni Battista Rizza was a person who lived a long time ago. He was born in a place called Italy in the year 1881. He did lots of cool things during his life that helped many people.
One of the things he did was become a doctor. Do you know what a doctor does? A doctor helps people when they are sick or hurt. They have special knowledge about how the human body works and how to make it feel better. Dr. Rizza worked really hard to learn all about how to be a good doctor.
Dr. Rizza also did something very important during his lifetime. He helped create vaccines to protect people from getting sick. Do you know what a vaccine is? It's like a superhero that keeps you safe from bad germs that can make you sick. When you get a vaccine, it helps your body build up its own superpowers to fight off the bad germs.
Dr. Rizza helped make vaccines to protect people from a disease called typhus. This disease could make people very sick and even cause them to die. But because of Dr. Rizza's hard work, many people could stay healthy and not get sick from typhus anymore.
Dr. Rizza did lots of other amazing things during his life, but the most important thing to remember is that he was a very helpful person who worked to make the world a better place. We should all try to be helpful like Dr. Rizza and do our part to make the world a better place too!