Nurses
wearing personal protective equipment (PPE) treat Ebola patients at the Kenema
treatment center run by the Red Cross Society on November 15, 2014 ©Francisco
Leong (AFP)
|
Sierra Leone has not
recorded a single new case of Ebola in the past four weeks, the authorities
said, keeping the west African country on course to being declared free of the
killer virus next month. The last two known Ebola patients were discharged from
hospital in late September, allowing Sierra Leone to begin the standard 42-day
countdown to becoming Ebola-free.
"Sierra
Leone has no Ebola-positive case recorded in the country for the fourth
consecutive week," the head of the government's National Ebola Response
Centre, Palo Conteh, said at a press conference, adding that there were no more
people in quarantine either.
AFP report continues:
Since
first emerging in December 2013, the worst outbreak of Ebola in history has
infected 28,000 people and left some 11,300 dead -- almost all in Sierra Leone,
Liberia and Guinea.
All
three countries have now gone two straight weeks without any new confirmed
cases, a new milestone in the fight against the haemorrhagic fever. Liberia has
already been declared free of transmission.
The
World Health Organization says a country can be declared Ebola-free 42 days
after the last confirmed case has tested negative twice for the virus, once
after each 21-day maximum incubation period.
For
Sierra Leone, that day falls on November 8.
But
the country's progress was overshadowed Wednesday by news of a study which
found that the virus may persist in some men's semen for nine months after they
were initially infected, longer than previously known.
The first long-term study
of its kind, published in the New England Journal of Medicine, adds to growing
evidence that Ebola can linger in the body, causing health problems for months
or even years.
Ebola May Persist In Semen For Nine
Months
The
Ebola virus may persist in some men's semen for nine months after they were initially
infected, far longer than previously thought, according to preliminary research
out Wednesday. The first long-term
study of its kind, published in the New England Journal of Medicine, adds to
growing evidence that Ebola can linger in the body, causing health problems for
months or even years.
The
findings raise new health concerns for the survivors of the Ebola epidemic that
has ravaged West Africa since late 2013, killing more than 11,000 people in the
deadliest outbreak since the virus was first identified in 1976.
AFP report continues:
AFP report continues:
"These
results come at a critically important time, reminding us that while Ebola case
numbers continue to plummet, Ebola survivors and their families continue to
struggle with the effects of the disease," said Bruce Aylward, the World
Health Organization's special representative on the Ebola response.
"This
study provides further evidence that survivors need continued, substantial
support for the next six to 12 months to meet these challenges and to ensure
their partners are not exposed to potential virus."
In
March, researchers published a study describing the case of a Liberian woman
infected with Ebola through sex with a survivor -- six months after his
infection was diagnosed.
"Before
this case, the furthest into convalescence that Ebola virus had been isolated
from semen was 82 days," said Armand Sprecher, an Ebola expert with
Doctors Without Borders.
The
first known case of sexual transmission of a virus within the Ebola family was
documented in 1967 when a woman was infected with Marburg virus through sex
with her husband, six weeks after he recovered, Sprecher added.
- Research findings -
A
total of 93 men from Sierra Leone enrolled in the study to examine semen
samples for the presence of Ebola virus genetic material.
The
men joined the study between two and 10 months after they were infected with
Ebola.
All
those who were tested in the first three months after their illness showed
positive results for Ebola in the semen.
Four
to six months after diagnosis, 65 percent were positive.
About
a quarter (26 percent) of those tested between seven and nine months were
positive.
It
remains unclear why some men retained fragments of Ebola virus and others did
not.
Researchers
are also unsure whether these trace levels could mean the men were still
infectious to partners.
The
US Centers for Disease Control and Prevention is conducting further tests to
determine if the samples contained live, potentially infectious virus.
- Survivors struggle -
There
are more than 8,000 male survivors of Ebola in Guinea, Sierra Leone and
Liberia, and experts are urging them to use condoms until their semen has twice
tested negative for Ebola.
People
who survive Ebola are considered cured once the virus is no longer detectable
in the bloodstream, typically within weeks of infection.
An
outbreak of Ebola in a given location can be declared over 42 days after the
resolution of the last case, according to the World Health Organization.
But
many experts now think that a period of increased surveillance and caution
should extend to 90 days, or even longer.
"This
is a highly important paper," said Susan McLellan, clinical associate
professor of Tropical Medicine at Tulane University.
"It
was known to some extent that the virus could persist in semen for a long time
after it cleared from blood but we really didn't know how long."
The
latest study was released just as a British nurse fell critically ill due to a
resurgence of the Ebola virus, following her successful treatment in January.
"This
virus is incredibly adept at hiding in places in our bodies considered immune
privileged sites, places where we don't have a lot of surveillance by the
immune system, such as the eyes and the testes," said Ilhem Messaoudi,
associate professor of biomedical sciences at the University of California,
Riverside.
"So even if you don't have the virus in your bloodstream it can be hiding out in these immune privileged sites and we need to be aware of that because it's setting the stage for potentially new outbreaks."
"So even if you don't have the virus in your bloodstream it can be hiding out in these immune privileged sites and we need to be aware of that because it's setting the stage for potentially new outbreaks."
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