The devastation wrought by the worst recorded
Ebola outbreak in history grows daily. As of Thursday, the deaths
totalled 729 deaths in West Africa, according to the World Health
Organization (WHO), but it’s far from over; ”Ebola is worsening in West
Africa,” CDC director Tom Frieden said not once, or twice, but three
times on Thursday.
Infectious disease experts are mobilizing, borders are
shutting down, and, despite the fact that there is no cure for Ebola
haemorrhagic fever (the illness caused by Ebola virus infection), health
care officials are trying anything they can to help the
stricken—especially those who put themselves at risk to save others.
That means digging deep into the list of experimental methods the WHO,
CDC and others have developed over the past few years to cure the deadly
viral infection—including a simple but controversial therapy called
immune plasma infusion.
In Monrovia, Liberia, 33-year old Dr. Kent Brantly of Forth
Worth, Texas had been treating Ebola patients since June, as part of an
international relief group called Samaritan’s Purse. But in mid-July,
Brantly recognized that he himself was showing symptoms of Ebola. He
isolated himself, and told the rest of the team of his suspicions; soon
after, his diagnosis was confirmed.
On Thursday Brantly was given a shot at survival: a
14-year-old male Ebola patient who had been under Brantly’s care, and
survived, donated a “unit of blood” to Brantly, according to Samaritan’s
Purse President Franklin Graham. “The young boy and his family wanted
to be able to help the doctor that saved his life.”
The idea—novel, though not unprecedented—is that the blood
(plasma, in medical parlance) of a survivor, full of antibodies proven
to be strong enough to fight off the disease (i.e., immune), when
transfused into an infected body, might help that body become immune
itself. Though it sounds a bit like something Hollywood might have
cooked up, there’s some science behind it—and an historical precedent
that offers hope.
By the time Robert Colebunders arrived in Kikwit,
Democratic Republic of Congo (known as Zaire at the time), on June 15 of
1995, the Ebola virus had ravaged the city of 250,000 and the
neighboring area for nearly 6 months. The hospitals in the riverport
town were empty; patients and healthcare workers had fled to other parts
of the country for fear of contracting the deadly disease, which would
ultimately affect 317 people and kill 245.
Eventually, the Kikwit Ebola outbreak was traced back to
January 1995, but it wasn’t until the start of May of that year that
local public health officials recognized the many sick patients in the
area as victims of the infectious disease. On May 8th, the Zairian
government officially declared the epidemic, asking the World Health
Organization to mobilize international assistance. Soon after,
infectious disease experts arrived from the WHO, the CDC, Doctors
Without Borders, the South African Medical Institute, the Red Cross, and
Belgium’s Institute of Tropical Medicine—which sent Colebunders.
Immediately, the team went to work to contain the disease.
“We rapidly began talking to local leaders, quickly helping
create an understanding in the population that an intervention was
needed,” says Colebunders. The team established a surveillance network
to identify and isolate patients who were suspected to have Ebola, and
distributed protective equipment that gave local health care workers the
ability—and the confidence—to safely work with the infected.
“We buried the dead bodies ourselves,” says Colebunders,
working with Red Cross volunteers. Not just the known Ebola victims,
either; every dead body in the area. The traditional burial rituals in
the area involve family members cleaning the dead body, mourners coming
to touch and kiss the body, and even keeping hair and nail as souvenirs.
“If its not done in the right way, they think the ghost of the person
will do them some harm,” says Colebunders. They had to convince them to
put the bodies in plastic bags, a hard sell anywhere. “Putting your
loved one in a plastic body bag is really not acceptable. That’s for
your trash,” Colebunders says. “You need to help them understand.”
It worked: soon enough, reports of newly infected patients petered out. They were near declaring victory.
Then, in the last days, a nurse at Kikwit General Hospital,
who had volunteered to care for a pair of Ebola-infected Italian nuns,
developed symptoms of Ebola hemorrhagic fever.
“The rest of the team became concerned,” says Colebunders,
and some of the medical professionals there who had suffered through and
survived an earlier infection (“convalescent patients” in the
literature) wanted to donate some of their blood to the nurse. “The
Americans and Scientists from the States didnt believe it could work,”
says Colebunders, but the Congolese doctors did it anyway. The same
blood transfusion procedure was repeated for seven others who were ill,
the final group of Ebola-stricken patients in the hospital.
The results were staggering: seven of the eight survived.
Typically, Ebola is almost unbelievably deadly; some
strains kill almost 90 percent of those they infect. It’s “very dramatic
and even preternatural,” says David Quammen, a journalist and author of
Spillover, a book documenting the impact of zoonotic diseases like
Ebola. “It kills people quickly and it kills a high proportion of the
people it infects.” The Kikwit case study (which would go on to be
published in the Journal of Infectious Diseases) showed an almost 90 percent survival rate.
There’s precedent for this treatment approach, too. “We use
this in other infectious diseases, and we can—and should—use that
experience and apply it to Ebola,” says Heinrich Feldmann, the head of
the National Institute of Health’s Laboratory of Virology. In Argentina,
for example, infection of the Junin virus is often (and effectively)
treated with blood transfusions from a Junin survivor.
So, why hasn’t the CDC, the WHO and the rest of the public
health organizations worldwide jumped all over immune plasma infusion
for Ebola? Why are we still scrambling for an Ebola treatment 20 years
later?
The answer is that it has been essentially impossible to
test. Why? Because Ebola only pops up occasionally, infects a relative
few, and kills most. There’s no way, says Feldmann, to get enough plasma
during an outbreak to treat others involved in that same outbreak. “Of
course if you are collecting plasma now for the next outbreak, then you
will have the time to do it,” Feldmann adds, though he is unaware of
anyone collecting plasma during the current West African outbreak.
At least, until the unnamed 14-year-old boy, who, of his
own accord, is about to become a key piece of the second test case in 20
years for what could be the treatment we’ve all been waiting for.
“We clearly need more effective ways to treat these patients and to
protect health care workers,” says Colebunders. “Confronted with such a
deadly disease, it is time to consider the use of experimental vaccines
and treatments as compassionate use.”
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