diff --git a/src/snmp_trap.cpp b/src/snmp_trap.cpp
index c9e85b7..497f0e4 100644
--- a/src/snmp_trap.cpp
+++ b/src/snmp_trap.cpp
@@ -41,7 +41,8 @@
         std::get<std::vector<std::string>>(propMap.at("AdditionalData"));
     for (auto& s : additionalData)
     {
-        message += " " + s;
+        message.append(" ");
+        message.append(s);
     }
     try
     {