The discovery that a novel, SARS-like coronavirus explains a cluster of pneumonia cases in Wuhan, China, now allows public health officials worldwide to identify infected people and contain the spread. But the virus, which closely resembles four bat coronaviruses that can infect human cells, has left researchers scrambling to answer many questions. One is the extent of spread, and a case of a Wuhan tourist in Thailand who was detected to have the disease underscores that it has the ability to travel quickly outside of the Chinese megacity. It also remains unclear which animals in the Wuhan seafood market are linked to the outbreak. Although no evidence exists of human-to-human transmission, the Chinese tourist in Thailand and a few of the other infected people in Wuhan say they did not visit the seafood market. Only one of 42 people who have confirmed cases of the disease has died, and he had serious underlying health issues. After criticism surfaced about potential delays in sharing information, Chinese scientists have made six sequences of the virus available, which has allowed other researchers to rapidly develop diagnostic tests and begin synthesizing the virus so it can be studied in animal markets. A major concern is the upcoming Lunar New Year on 25 January, during which hundreds of millions of people travel around the country and could potentially spread the infection.