There are about 20 billion chickens in the world today, more than any other bird. <break time="2s"/> Most of them have been raised on large farms for meat or eggs.
Maurice Hilleman was a scientist. He studied microbiology, single cell organisms that cause infectious diseases, like COVID. He also created vaccines to protect children. Use this story to talk about disease and ways that we protect ourselves from disease, including hand washing, wearing masks, social distancing and getting vaccinated.