How to escape ampersand in environment variable

Travis CI Discussions & Feedback
1

I have this value of environment variable for travis:

WGaSDdq1&kL0Ua3eB

But travis complains:

We were unable to parse one of your secure environment variables. Please make sure to escape special characters such as ’ ’ (white space) and $ (dollar symbol) with \ (backslash) . For example, thi$isanexample would be typed as thi$isanexample. See Encryption keys - Travis CI.

I was trying to escape this value this ways:

WGaSDdq1\&kL0Ua3eB 
WGaSDdq1^&kL0Ua3eB 
WGaSDdq1&kL0Ua3eB

But result is either wrong result value or value is unable to parse for Travis. Can someone please help me?