NBC says the freelancer was hired on Tuesday to work with the broadcaster's chief medical correspondent, Nancy Snyderman, who is reporting from Monrovia.
NBC News president Deborah Turness said in a message to staff that NBC was taking "all possible measures" to protect employees and the general public.
Snyderman and the rest of the NBC crew would also be flown home and put in quarantine for 21 days, the maximum incubation period, Turness says.