diff --git a/backend/server.js b/backend/server.js
index 6680196..20d9312 100644
--- a/backend/server.js
+++ b/backend/server.js
@@ -33,7 +33,6 @@ async function run() {
   console.log("Started watching changes in database");
 
   const writeMessage = (response, blob) => {
-    // TODO: why no id?
     const id = blob._id || null
     const message = `id: ${id}\nevent: message\ndata: ${JSON.stringify(blob)}\n\n`
     response.write(message)
@@ -55,7 +54,10 @@ async function run() {
         });
 
     const changeListener = async (change) => {
-      writeMessage(response, change.fullDocument)
+      // Ignore events without fullDocument, e.g. deletes.
+      if (change.fullDocument) {
+        writeMessage(response, change.fullDocument)
+      }
     }
     changeStream.on("change", changeListener);
     response.on('close', () => {