It has been noted that frequent flyers are being targeted via email with messages that seem to be receipts for e-tickets supposedly purchased via a credit card that contain a virus. If recipients open the email attachment, their computers are then attacked with the malicious software.
The airlines being aligned with the unpleasant emails include United, Northwest, JetBlue, Midwest, Sun Country, Virgin America and possibly others. Don’t be fooled. Do not open, forward or store the message. Delete. And it’s advisable to delete it from your “deleted items” folder as well.