COVID-19 is a flu-like illness caused by infection from SARS-2-CoV, a coronavirus which emerged in late 2019 in Wuhan, China. While there is still much we don't know about the virus, coronaviruses like this one are zoonotic, meaning they can be shared between humans and animals. Phylogenetic research of the virus has shown it is closely related to SARS.
While it can be difficult to stay on top of SARS-2-CoV's spread, this tool courtesy of Johns Hopkins Center for Systems Science and Engineering is helpful for doing just that.
Ultimately, for most, COVID-19 presents much in the same way that a flu or cold would, with a cough, fever, and other respiratory symptoms. Guidance from the Centers for Disease Control (CDC) suggests that symptoms likely begin between two and 14 days after exposure. If you believe that you have been exposed or if you have recently traveled from an area with ongoing community spread, call your healthcare professional, do not simply show up at a hospital or doctor's office.
Coronaviruses are most often spread person to person from either close contact or through respiratory droplets produced when a person coughs or sneezes. Surgical masks are not particularly effective at preventing you from becoming ill and buying them may actually prevent healthcare workers who are at highest risk for infection from being able to access them.
As far as travel goes, please follow the guidelines from the Centers for Disease Control (CDC) which are being updated constantly.
Here are some other helpful resources about SARS-2-CoV/COVID-19: