France's health ministry stressed that the risk to the population was "very low". Likewise, WHO chief Tedros Adhanom Ghebreyesus said "the risk to the rest of the world is low" and that there was "no need to panic".
Efforts are underway to trace people who may have been in contact with the doctor.
Healthcare workers are especially at risk from Ebola, which is spread through bodily fluids.
Last week WHO said 17 of the 75 health workers who had caught Ebola in DR Congo had died.
The current Ebola outbreak was caused by the Bundibugyo species of the virus, for which there is currently no vaccine.
France has set up a "dedicated monitoring system" for aid workers returning from DR Congo, the health ministry said.
According to both Africa's Centres for Disease Control and Prevention (Africa CDC) and US public health authorities, the current Ebola outbreak has the potential to be one of the largest ever.
In DR Congo, cases are currently concentrated in the eastern provinces of Ituri, South Kivu and North Kivu.
Ituri remains the main centre of transmission, accounting for more than 90% of confirmed infections.
The WHO has warned that conflict in eastern DR Congo is making it more difficult to tackle the Ebola outbreak. The M23 rebel group is in control of large parts of both North and South Kivu.
