Let's have a vaccine. Recently, I read a report that an isolated infection occurred in the western region of the United States in mid December. Antibodies were also found in other states in early January before it was known that the virus had been introduced into these places. A study showed that covid-19 infection had been found in the United States in December 2019, providing further evidence that the first case of coronavirus had been reported in China and spread around the world a few weeks ago. Therefore, the virus is likely to spread in the United States as early as possible. Only China has reported it first. For their own safety, students abroad must be well protected, vaccinated and protected.