China has now reported 45 cases linked to the virus, Centers for Disease Control and Prevention (CDC) official Nancy Messonnier told reporters in a press call, most linked to a seafood and live animal market in Wuhan, while two cases have been found in Thailand and one in Japan.
The CDC said that based on current information, the risk to Americans from the virus, known by its technical name 2019-nCoV, is currently deemed low. Nevertheless it was enhancing precautionary measures.
The CDC will deploy 100 additional staff to the three airports, with incoming passengers asked to fill out a questionnaire and submit to a temperature check.
Those who show possible signs will be shifted to another facility for additional screening and a rapid diagnostic test.
Messonnier said that this test would currently take around a day, "but it's going to get rapidly faster" as the diagnostic tool improves.
The UN's health agency says that the outbreak of the disease comes from a never-before-seen strain belonging to a broad family of viruses ranging from the common cold to more serious illnesses such as SARS.