diff --git a/ted_sws/event_manager/model/event_message.py b/ted_sws/event_manager/model/event_message.py
index 4fd990465..d754a1aa0 100644
--- a/ted_sws/event_manager/model/event_message.py
+++ b/ted_sws/event_manager/model/event_message.py
@@ -14,7 +14,7 @@
 """
 
 
-class EventMessageProcessType(Enum):
+class EventMessageProcessType(str, Enum):
     """
     Event message process type.
     """