A "staffer" is a person who works as a member of a staff or a group of people employed by an organization. They perform various roles and tasks to support the functioning of a company or an individual. Full definition
It is common practice for a sitting president to maintain a war room of staffers who are responsible for monitoring media coverage of the president and his administration. (fortune.com)
The organization struggled to set up meetings with key staffers for the nominees. (educationnext.org)
During the 1990s, he points out, fewer people chose mining careers, resulting in a shortage of staffers who'd now be in their 40s and 50s. (miningrecruitmentgroup.com)