What would happen if t. brucei suddenly loss the ability to undergo antigenic variation

If T. brucei suddenly loses the ability to undergo antigenic variation It will be easier for the body's immune system to expel T. brucei and prevent infection.

Explanation:

Antigenic variation is a strategy adopted by both bacteria, viruses and parasites, and is characterized by genetic mutations that can modify epitopes that were previously recognized by antibodies or other components of the immune system, thus making it difficult to eliminate the infectious agent.  For this reason we can state that  if T. brucei suddenly loses the ability to undergo antigenic variation It will be easier for the body's immune system to expel T. brucei and prevent infection.