All situations can be turned to your advantage, even the bad ones.. though that is a bit tricky. Even if you are not able to repair all of the damage caused by negative publicity, you can give it a positive spin
1. First of all apologize if the negative occurence is because of your actions or misjudgement. Take responsibility for your actions and sincerely implement measures not to repeat it in the future.
2. Create consistent key messages for communication with the media and stakeholders.
3. Issue a press release on steps being taken to address the issue and provide follow up stories to reporters on the results achieved.
4. In some cases, it is even important to advertise on the measures being taken. This will help to create wider consumer awareness.
5. In the case where consumer confidence in the company or its products come under scrutiny, it is important to set up a forum or helpline to address consumer concerns.
All is not lost, people appreciate the fact that you have taken responsibility for your actions and are genuinely interested in making amends and setting up systems in place not to repeat such mistakes in the future.