WASHINGTON – U.S. health officials offered a reality check Tuesday about the scary new virus from China: They're expanding screenings of international travelers and taking other precautions but for now, they insist the risk to Americans is very low. “At this point Americans should not worry for their own safety,” Health and Human Services Secretary Alex Azar told reporters Tuesday. China has confirmed more than 4,500 people with the respiratory illness, which in severe cases can cause pneumonia, with dozens more counted in other countries.