The Scottish nurse who contracted the Ebola virus in West Africa will be treated with a combination of blood samples from survivors of the virus and an experimental anti-viral drug.
Dr. Michael Jacobs, who leads the team treating Pauline Cafferkey at the Royal Free hospital in London, said she was “as well as we could hope for” and was sitting up in an isolation tent and able to eat, read and talk.
Her family has reportedly been keeping a bedside vigil since she was admitted to the hospital on Tuesday morning after becoming the first person diagnosed with Ebola on UK soil.
Dr. Jacobs said that Cafferkey was not able to have physical contact with her family but was talking to her parents via an internal communication system. He also said she has been actively participating in conversations about her medical care and has agreed to all proposed treatments.
“She’s a nurse, a fellow professional, so we have been able to discuss things in great detail,” he said.
While he didn’t name the anti-viral drug that would be used to treat Cafferkey, he did say that “it has been used extensively in people previously for different reasons, and it has a very good safety record in humans which has encouraged us to use it in this experimental way.”
However, he added, “at the moment, we don’t know what the best treatment strategies are. That’s why we’re calling them experimental treatments.”
In addition to the anti-viral medication, Cafferkey will also receive an experimental transfusion of antibody-rich convalescent serum (blood products) from a recovered Ebola patient. Dr. Jacobs said there were several stocks of this plasma around Europe, including that of British Ebola survivor William Pooley, who was cured of the virus at the Royal Free Hospital in September.
“When the need arises, the various experts around Europe convene a conference, and decide the most appropriate plasma for the patient. It’s plasma from a patient who has survived from Ebola and is treated in Europe,” said Dr. Jacobs.
Challenges of experimental treatments
Although several potential Ebola drugs exist, there is very little evidence that any of them work. Two of the most promising anti-viral drugs are brincidofovir and favipiravir. Tests in tissue samples suggest the anti-virals have the potential to stop Ebola replicating once it infects cell. Brincidofovir has been tried on some patients in the US and both drugs have entered clinical trials in West Africa. However, the results are not expected until February.
The effectiveness of using the blood of survivors is equally uncertain until the results of trials come through. The rationale behind the approach is that blood from recovered patients contains antibodies and other components that may help the transfused patient fight off the virus. Antibodies are produced by the body’s immune system to fend off harmful things such as viruses. They remain in the blood ready to fight off any future infections by the same foreign substance.
Blood from survivors of diseases including bird flu and anthrax has been used in the past when doctors ran out of options and seems to work best in diseases where there’s a toxin, such as anthrax and tetanus. Several patients in the current outbreak have received blood-product transfusions from survivors, but scientists can’t say whether their recovery was due to the treatment or to better care among the transfused patients than other Ebola patients.
Ebola therapies and vaccines are now being tested at unprecedented speed during this outbreak, but for patients infected today, doctors simply do not know if these experimental options will make a difference.