diff --git a/zerver/lib/queue.py b/zerver/lib/queue.py
index 39831ebe9a..ed5a316a99 100644
--- a/zerver/lib/queue.py
+++ b/zerver/lib/queue.py
@@ -305,7 +305,7 @@ def get_queue_client() -> SimpleQueueClient:
 queue_lock = threading.RLock()
 
 def queue_json_publish(queue_name: str,
-                       event: Union[Dict[str, Any], str],
+                       event: Dict[str, Any],
                        processor: Callable[[Any], None]=None) -> None:
     # most events are dicts, but zerver.middleware.write_log_line uses a str
     with queue_lock:
diff --git a/zerver/middleware.py b/zerver/middleware.py
index 8dfe0fe4eb..c77799433b 100644
--- a/zerver/middleware.py
+++ b/zerver/middleware.py
@@ -211,7 +211,8 @@ def write_log_line(log_data: MutableMapping[str, Any], path: str, method: str, r
         logger.info(logger_line)
 
     if (is_slow_query(time_delta, path)):
-        queue_json_publish("slow_queries", "%s (%s)" % (logger_line, email))
+        queue_json_publish("slow_queries", dict(
+            query="%s (%s)" % (logger_line, email)))
 
     if settings.PROFILE_ALL_REQUESTS:
         log_data["prof"].disable()
diff --git a/zerver/tests/test_queue_worker.py b/zerver/tests/test_queue_worker.py
index a6cc0e4116..80b6bdaaec 100644
--- a/zerver/tests/test_queue_worker.py
+++ b/zerver/tests/test_queue_worker.py
@@ -71,9 +71,11 @@ class WorkerTest(ZulipTestCase):
     def test_slow_queries_worker(self) -> None:
         error_bot = get_system_bot(settings.ERROR_BOT)
         fake_client = self.FakeClient()
+        # TODO: Rewrite this set part of the test by just mocking
+        # `is_slow_query` to generate the events.
         events = [
-            'test query (data)',
-            'second test query (data)',
+            {'query': 'test query (data)'},
+            {'query': 'second test query (data)'},
         ]
         for event in events:
             fake_client.queue.append(('slow_queries', event))
diff --git a/zerver/worker/queue_processors.py b/zerver/worker/queue_processors.py
index 74dd2a30f5..cbded28ed2 100644
--- a/zerver/worker/queue_processors.py
+++ b/zerver/worker/queue_processors.py
@@ -390,11 +390,9 @@ class SlowQueryWorker(LoopQueueProcessingWorker):
     # Sleep 1 minute between checking the queue
     sleep_delay = 60 * 1
 
-    # TODO: The type annotation here should be List[str], but that
-    # creates conflicts with other users in the file.
-    def consume_batch(self, slow_queries: List[Any]) -> None:
-        for query in slow_queries:
-            logging.info("Slow query: %s" % (query,))
+    def consume_batch(self, slow_query_events: List[Dict[str, Any]]) -> None:
+        for event in slow_query_events:
+            logging.info("Slow query: %s" % (event["query"],))
 
         if settings.SLOW_QUERY_LOGS_STREAM is None:
             return
@@ -402,12 +400,12 @@ class SlowQueryWorker(LoopQueueProcessingWorker):
         if settings.ERROR_BOT is None:
             return
 
-        if len(slow_queries) > 0:
+        if len(slow_query_events) > 0:
             topic = "%s: slow queries" % (settings.EXTERNAL_HOST,)
 
             content = ""
-            for query in slow_queries:
-                content += "    %s\n" % (query,)
+            for event in slow_query_events:
+                content += "    %s\n" % (event["query"],)
 
             error_bot_realm = get_system_bot(settings.ERROR_BOT).realm
             internal_send_message(error_bot_realm, settings.ERROR_BOT,