You Do Need power plug adapter while traveling from United States Virgin Islands to Belgium.

Here is Why You Need An Adapter

The outlet and plug type used in Belgium are C and E and in United States Virgin Islands are A and B. This is how they look like.

United States Virgin Islands

In United States Virgin Islands, outlets of type A and B are in use.

Type A

Type B

Belgium

In Belgium, outlets of type C and E are in use.

Type C

Type E