What does CDC USA rank Vietnam as a 'contagious community'?

According to this list, Vietnam is not in the 3 levels of travel restriction warning recommended by the Centers for Disease Control and Prevention (CDC) of US citizens.

On February 20, the US Centers for Disease Control and Prevention (CDC) introduced Vietnam to a group of countries and territories 'with the spread of COVID-19 in the community'. Some people were bewildered by this information of the CDC in the situation that COVID-19 is happening complicatedly.

However, this information is actually a notice of the CDC to provide information and recommendations for US citizens when abroad.

The CDC's full notice outlines four levels of warnings about disease outbreaks and recommendations for Americans.

Level 3 alert (highest level)

The highest level of warning is for China. CDC recommends that US citizens avoid all trips to China if it is not absolutely necessary.

Warning level 2

This group includes Japan and Korea. These are countries with prolonged disease spread in the community. The CDC also warns older adults and people with chronic conditions to consider delaying travel if it is not needed.

Warning level 1

At this alert level, the CDC does not recommend canceling or postponing trips to these destinations - currently on the list includes Hong Kong. CDC also advises Americans to visit locations within this group to take common precautions.

Which group does Vietnam belong to?

In this recommendation of CDC, Vietnam is not included in the above three-level warning book of CDC . The group that CDC classified Vietnam as the group is associated with the phrase 'apparent community spread' - roughly, there is a recognized community spread.

In addition to Vietnam, there are Iran, Singapore, Thailand and Taiwan.

The CDC explains that 'there is community spread' means that someone has been infected with the virus, including uncertain where and how it was spread. However, the spread did not increase, or was not large enough to make recommendations regarding travel to the above countries and territories. In case the list has changed, CDC will update quickly.

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