More than 100 people have now died from the new coronavirus. The number of people infected in mainland China increased sharply in one day, from 2,700 Monday to more than 4,500 Tuesday. The increase comes even as China takes strong measures to contain the spread of the disease. Coronaviruses are a large family of viruses that cause disease in mammals and birds. Coronaviruses can cause illnesses that range from the common cold to much more severe illnesses like Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Experts still do not have a clear picture of the severity of the new coronavirus. Officials are calling the disease a “novel” or new coronavirus because it has not been found before in humans. The newly identified virus is thought to have spread to humans from wild animals sold at a market in Wuhan, in central China’s Hubei province. But it is now spreading between people.