World Health Organization researchers issued a dire new forecast for the Ebola epidemic Tuesday, one that sees 20,000 cases by November, much sooner than previous estimates. And 70 percent of patients are dying.
That's a big increase over the previous estimates of a 50 percent fatality rate.
“These data indicate that without drastic
improvements in control measures, the numbers of cases of and deaths
from Ebola virus disease are expected to continue increasing from
hundreds to thousands per week in the coming months,” the WHO Ebola
Response Team, led by Dr. Christopher Dye, wrote in a report rushed into
print by the New England Journal of Medicine.
This projection includes nearly 10,000 people in
Liberia alone. WHO said earlier Monday that more than 5,800 people had
been infected with Ebola and more than 2,800 had died of it since the
virus first broke out in Guinea in December.
And it's likely far worse, especially in
Liberia, WHO says. "The true number of deaths will likely never be
known, as bodies in the notoriously poor, filthy and overcrowded West
Point slum, in the capital, Monrovia, have simply been thrown into the
two nearby rivers," WHO said in a separate statement.
But forget about the tales of horrific bleeding
from the eyes nose and mouth. Bleeding is one of the most unusual
symptoms, the team of experts from around the world said.
Still, it’s looking so bad that Ebola could take
permanent hold in West Africa, they said — something that’s never
happened before. “For the medium term, at least, we must therefore face
the possibility that Ebola virus disease will become endemic among the
human population of West Africa,” they said.
What could change that? Quick action by the
world, the experts said. That means sending more people to track down
potential Ebola cases so they can be isolated and treated, providing
better hospital treatment and safer burials, and getting better buy-in
from the community. In some places, residents still don’t believe Ebola
is a virus, and they have attacked and even killed health workers trying to spread the word about the danger.
Patients are also running away and spreading the disease that way.
To stop the epidemic, transmission must be cut
in half, they said. “Considering the prospects for a novel Ebola
vaccine, an immunization coverage exceeding 50 percent would have the
same effect,” they wrote.
The United States is leading a new response, sending troops
and supplies and offering to help coordinate help. WHO and the UN are
urging other countries to help. Germany, France, Cuba and China are
among countries also sending teams and equipment.
To make the forecast, the team looked at all the
available data on the epidemic, which has spread more widely than any
previous outbreak of Ebola, in part because it broke out in an area
where people travel widely across borders.
It remains clear that close contact with an
infected person or their bodily fluids are needed for infection to
happen. There’s nothing mysterious about how Ebola spreads, and it's not
as easily transmitted as influenza or measles.
Caregivers and health care workers have a high
risk. More than 300 health care workers have been infected, and half of
them have died.
The most common first symptoms are fever and
fatigue. Hemorrhage — the most feared symptom — is seen in fewer than 5
percent of patients, although about 18 percent had unexplained bleeding,
the WHO team said.
Ebola has an incubation period of 11 days, and
people cannot infect others before they begin to show symptoms — unlike
flu, which people can pass along before they even feel ill.
One important number is how many other people
each patient infects. It’s different for each country, Dye says — an
average of 1.7 in Guinea and 1.8 in Liberia. In Sierra Leone, an
infected person sickens two other people on average. Some patients
infect many more people than that — than a dozen mourners were infected
at the funeral of a single traditional healer who died in Sierra Leone,
for instance. And some die or recover without infecting anybody else.
Another important number is what’s called
doubling time — how long it takes the number of cases to double. This
varies greatly from country to country; in Guinea it’s just under 16
days, in Liberia it’s nearly 23 days and in Sierra Leone it’s 30 days.
That’s what leads to the projection of 20,000 cases by Nov. 2. “The true
case load, including suspected cases and undetected cases, will be
higher still,” the WHO team wrote.
Most of those infected are ages 15 to 44,
although people those ages only account for 44 percent of the population
in those countries. Older patients are more likely to die, and those
who have diarrhea, hemorrhage, difficulty breathing or confusion also
seem more likely to die.
Most of those who died succumbed on average four
days after they were admitted to a hospital or clinic, and if someone
survived, it was usually 11 days before they were better enough to go
home, on average. It’s possible that patients who get hospital care live
longer, the researchers said, but there’s not enough information to say
that for sure.
Patients get vastly different care, depending on
where they are treated. Three out of four patients treated in the U.S.
have recovered or nearly recovered and the fourth has released little
information about his condition. They all got the best possible care, including carefully measured and balanced rehydration, 24-hour nursing care, immaculate conditions and experimental treatments, including drugs and transfusions of blood from patients who have recovered.
In West Africa, some lucky patients get good
hospital care that includes saline to replace fluids lost to vomiting
and diarrhea, antibiotics to prevent other infections, and pain control.
But many are given little more than a bed or a space on the floor, and
many are also turned away to die at home or in the streets. So it’s hard
to say what will save someone’s life.
The report strongly suggests what doctors is
saying is true — there’s nothing unusual about the virus itself, say Dr.
Peter Piot of the London School of Hygiene and Tropical Medicine, who
helped discovered Ebola, and Dr. Jeremy Farrar of Britain’s Wellcome
Trust.
It’s spreading because of dysfunctional health systems, a lack of action by local and international governments and
a population that hasn’t caught on immediately to the dangers and what
to do about Ebola, they wrote in a commentary in the journal.
“Classic ‘outbreak control’ efforts are no longer sufficient for an epidemic of this size,” they added.
“Rather, what’s required is a large-scale,
coordinated humanitarian, social, public health and medical response,
combining classic public health measures with safe and effective
interventions including behavioral changes, therapies and, when
possible, vaccination.”
It will take both a “massive” response and, probably, the use of new treatments and vaccines to control the epidemic, Farrar and Piot wrote.
“But we must also look to the future. There will
be more epidemics and outbreaks of Ebola and other new or re-emerging
infections,” they added. “Yet our response to such events remains slow,
cumbersome, poorly funded, conservative and ill-prepared.”
Wednesday, 30 September 2015
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