The World Health Organization (WHO) and the Congolese authorities are proposing changes to how some Ebola patients are cared for, new guidelines show, after a patient's death.
There are many unanswered questions surrounding the circumstances of the woman's death in the DRC, which has not previously been reported.
But it has raised concerns because of the woman, whose name has not been released for confidentiality reasons, because of Ebola and died.
"That was a big red flag event for all of us," said Janet Diaz, who leads the WHO's clinical management team for the epidemic in the DRC.
DRC's Ebola outbreak has infected over 3,000 people and killed more than 2,000 since August last year.
It is the second-worst outbreak after one in West Africa between 2013 and 2016 that killed more than 11,000 people.
The woman was working as a caregiver in the high-risk "red zone" of a treatment center in Beni, eastern DRC, according to health officials familiar with her case.
Ebola survivors, although some researchers have considered them to be at least a theoretical possibility.
Their presumed immunity allowed for closer contact with sufferers, many of them children.
Alima, the medical charity that co-ran the Center of Me, where she worked, said she tested positive for Ebola and died in July.
But it is not known if the woman received a false positive result.
Ebola survivors' immunity is fully understood. Ebola patients across eastern DRC.
The WHO and Congolese officials have drafted new guidelines, seen by Reuters news agency, that warn that some Ebola survivors may have "incomplete immunity."
The new protocols would set limits on which Ebola survivors could work.
Survivors who had mild cases of Ebola and who were found to have low viral loads "The draft says.
Diaz said the protocols were still being discussed.
Questions about immunity
Efforts to contain the DRC outbreak have been hampered by insecurity and public mistrust, but aided by medical advances including new vaccines and therapies.
Ebola survivors, known as "les vainqueurs" – French for "the victorious" – have been at the forefront of treatment, offering vital care, especially to children.
Their assumed immunity has meant that they can spend more time and provide much-needed human contact. The protective gear they must wear is lighter and less restrictive than that worn by other health workers.
But the draft protocols would be discussed by the health authorities.
These include people whose immune systems may be weaker because they are pregnant or because they have HIV or tuberculosis.
The woman who died was pregnant at the time, according to Nicolas Mouly, Alima's emergencies coordinator. But it is not known if it played a role in every falling sick again.
Mouly said the DRC's biomedical research institute. Officials with the DRC's Ebola response and the institute did not respond to phone calls and text messages seeking comment.
Ebola survivors working with Ebola patients, WHO's Diaz said. They have also reminded treatment centers to ensure their employees are following biosafety rules.
Much remains unknown about how immunity works in Ebola survivors, including how treatments can affect a patient's susceptibility to reinfection.
"I think that's the big question: What is the true immunity of an Ebola patient who survived?" Diaz said.
"Everyone's working very hard right now."
There have been several confirmed cases of relapse with Ebola, including a Scottish nurse who was infected in Sierra Leone in 2014 and fell ill again 10 months after recovery.
But the symptoms have tended to be localized in certain parts of the body, and according to Raina MacIntyre, who heads the Biosecurity Program at the University of New South Wales' Kirby Institute.
Ebola River in northern Congo in 1976.
Short-term immunity has been treated as a given. Ebola outbreak in 1976 Ebola virus proteins 40 years later.
Alima's Mouly said that the creation of a standardized set of rules for survivors was a positive step.