diff --git a/enferno/app.py b/enferno/app.py
index 15ef748af..9ab916902 100755
--- a/enferno/app.py
+++ b/enferno/app.py
@@ -142,6 +142,20 @@ def register_extensions(app):
     security = Security(app, user_datastore, **security_options)
 
     session.init_app(app)
+
+    # Background polls (e.g. the notification poller) carry X-Silent-Poll and must
+    # not slide the server-side session, otherwise the idle timeout never fires.
+    from types import MethodType
+    from flask import request
+
+    def _should_set_storage(self, app, sess):
+        if request.headers.get("X-Silent-Poll") and not sess.modified:
+            return False
+        return sess.modified or app.config["SESSION_REFRESH_EACH_REQUEST"]
+
+    app.session_interface.should_set_storage = MethodType(
+        _should_set_storage, app.session_interface
+    )
     babel.init_app(app, locale_selector=get_locale, default_domain="messages", default_locale="en")
     rds.init_app(app)
     mail.init_app(app)
diff --git a/enferno/static/js/mixins/notification-mixin.js b/enferno/static/js/mixins/notification-mixin.js
index fd849de5d..c75cb5a73 100644
--- a/enferno/static/js/mixins/notification-mixin.js
+++ b/enferno/static/js/mixins/notification-mixin.js
@@ -126,6 +126,8 @@ const notificationMixin = {
       }
     },
     async loadNotifications(options) {
+      const { silent, ...loadOptions } = options || {};
+      options = loadOptions;
       const isFirstPage = options?.page === 1;
       const status = this.notifications.status;
 
@@ -153,7 +155,8 @@ const notificationMixin = {
         }
 
         const queryParams = new URLSearchParams(query);
-        const { data } = await axios.get(`/admin/api/notifications?${queryParams.toString()}`);
+        const config = silent ? { headers: { 'X-Silent-Poll': '1' } } : undefined;
+        const { data } = await axios.get(`/admin/api/notifications?${queryParams.toString()}`, config);
 
         if (!data) return;
 
@@ -255,7 +258,8 @@ const notificationMixin = {
       }
     },
     async refetchNotifications() {
-      this.loadNotifications({ page: 1 });
+      // Automatic background poll: must not slide the idle session timeout.
+      this.loadNotifications({ page: 1, silent: true });
     },
     decrementNotificationsCount() {
       if (this.notifications.unreadCount > 0) {
diff --git a/tests/test_session_poll_refresh.py b/tests/test_session_poll_refresh.py
new file mode 100644
index 000000000..34c37def8
--- /dev/null
+++ b/tests/test_session_poll_refresh.py
@@ -0,0 +1,45 @@
+"""Verify the notification poll no longer slides the server-side session TTL.
+
+A request carrying X-Silent-Poll must NOT refresh the session expiry, so an idle
+user is eventually logged out. A normal request must still refresh it.
+"""
+
+
+def _session_key(app):
+    client = app.session_interface.client
+    keys = [k for k in client.keys() if b"session" in k or k.startswith(b"session:")]
+    assert keys, f"no session key in store; keys={client.keys()}"
+    return client, keys[0]
+
+
+def test_silent_poll_does_not_refresh_ttl(app, admin_client):
+    admin_client.get("/admin/api/notifications")
+    client, key = _session_key(app)
+
+    # Simulate idle time passing: 100s from expiring.
+    client.expire(key, 100)
+    assert client.ttl(key) <= 100
+
+    # Background poll carries the silent header.
+    resp = admin_client.get("/admin/api/notifications", headers={"X-Silent-Poll": "1"})
+    assert resp.status_code == 200
+
+    refreshed = client.ttl(key)
+    print(f"\nTTL after silent poll (was forced to <=100): {refreshed}")
+    assert refreshed <= 100, "silent poll still refreshed the session TTL"
+
+
+def test_normal_request_still_refreshes_ttl(app, admin_client):
+    admin_client.get("/admin/api/notifications")
+    client, key = _session_key(app)
+
+    client.expire(key, 100)
+    assert client.ttl(key) <= 100
+
+    # Normal (non-silent) request: a real user action.
+    resp = admin_client.get("/admin/api/notifications")
+    assert resp.status_code == 200
+
+    refreshed = client.ttl(key)
+    print(f"\nTTL after normal request (was forced to <=100): {refreshed}")
+    assert refreshed > 100, "normal request should still refresh the session TTL"