Health experts have a new warning about Zika virus. They say the virus will keep spreading before the Zika epidemic finally ends. The experts say a new model shows a very large number of people could become infected before then. The model is a project of researchers from England, Sweden and the United States. They estimate the Zika virus could infect over 93 million people in South America, North America and the Caribbean. The model projects 1.6 million young women could be infected. Experts say a woman who is infected during the early months of her pregnancy is at risk of giving birth to a baby with microcephaly. A baby born with microcephaly has a small head and brain. The condition causes mental and physical disability, seizures and sometimes death. But experts say not every pregnant woman infected with Zika will give birth to a child with severe birth defects.