In 2009 Qualys and Sourcefire integrated their services (see the original full brief on the integrations listing). In October of 2013 Cisco completed the acquisition of Sourcefire. What was Sourcefire 3D, which had been named Defense Center, was to be named FireSIGHT Management Center.
As of writing, this service is now called Firepower Management Center.
Cisco still supports this Host Input Connector, named "Sourcefire Qualys Connector" or just "Qualys Connector", which you can find here. The latest available version as of writing is 1.0.1-8 from June 27th, 2013.
Please see the FireSIGHT Qualys Connector Configuration Guide for help on configuring the connector.
Should you run into difficulties with the Qualys Connector, please contact Cisco TAC.