c# - Is it dangerous with a while(true) in silverlight?

Question

I have this backgroundworker:

    MyBackgroundWorker.DoWork += ((sender, arg) =>
        {
            while (true)
            {
                client.GetkFailuresCompleted += ((s, e) =>
                {
                    int[] arr = JsonHelper.Deserialize<int[]>(e.Result);

                    int error = (int)((arr[0] / (double)arr[1]) * 100);

                    Debug.WriteLine("Error %: " + error);

                    this.Dispatcher.BeginInvoke(() =>
                        {
                            ErrorOverviewPointCollection.Clear();
                            ErrorOverviewPointCollection.Add(new Point(1, 100 - error));
                            ErrorOverviewPointCollection.Add(new Point(1, error));
                        });
                });
                client.GetFailuresAsync();

                Thread.Sleep(5000);
            }
        });

And as you see Im running it forever. I'm not implementing any stop/fail functions to stop the BackgroundWorker, but do I need to? If the user closes the browser the application should stop right?

The DoWork accesses a webservice that on completion updates a ObservableCollection that is databound to the silverlight application.