A debate is raging over proposals that a second vaccine be introduced to fight Ebola in Democratic Republic of Congo, currently in the grip of its worst outbreak.
The DR Congo
Health Minister, Dr Oly Ilunga, who resigned after being stripped of management
of the country's Ebola response, said the current vaccine is the only one that
has been proven to be effective, and an opposition MP said the new vaccine is
untested, and fears people in the country will be used as guinea pigs.
Leading health
experts say the second vaccine is safe and could be an important tool in
holding back the spread of the virus.
Tried and
tested?
It has been
tested on 6,000 people and "has shown outstanding safety," says
Professor Peter Piot, a leading expert on Ebola and director of the London
School of Hygiene & Tropical Medicine, which has been involved with
pharmaceutical company Johnson & Johnson in the development of the vaccine.
A woman being screened for Ebola test
Studies have
shown that although the drug is still in the experimental phase and hasn't been
tested on patients with Ebola, it has proved highly effective in tests on
primates (animals genetically close to humans).
The only way to
test it on humans is for it to be used in an outbreak scenario, as it wouldn't
be safe to trial the medicine on volunteers infected with the virus in a
clinical trial.
This is how the
first vaccine - by the Merck & Co drug company - was successfully deployed
in Guinea in 2015.
It was rolled
out for "compassionate use" which allows for the use of an unlicensed
drug (licenses can take years or decades to get) when no other options are
available, but only with authorisation from the government of the affected
country.
World Health
Organization (WHO) data shows the Merck vaccine has a 97.5% efficacy rate for
those who are immunised, compared to those who are not.
The WHO says
this vaccine is proven safe and effective against Ebola, but that more testing
is still needed for it to be licensed.
So, we're in a
similar place with the new vaccine as we were in 2015 with the current one -
there's substantial evidence that it's safe and that it could be effective, but
it hasn't been tested in an outbreak, and hasn't been licensed.
Is there enough
vaccine?
In July, the WHO
Emergency Committee said it "recognises the shortage of supply" of
the Merck vaccine.
Dr Josie Golding
of the Wellcome Trust, says it's likely there won't be enough of the vaccine to
deal with the current outbreak.
"If so,
this would have devastating consequences. We strongly believe there is an
urgent need to deploy and assess a second Ebola vaccine, developed by Johnson
and Johnson."
In the short
term, the available doses of the vaccine may be sufficient, but not if the
outbreak persists.
The Merck drug
firm says there is enough vaccine to immunise nearly 500,000 individuals at the
current dose, and is in the process of producing more.
About 1.5
million doses of the vaccine are available.
There are around
10 million people in the two affected provinces combined.
The current
vaccine is only being given to health workers and people who might have been
exposed to the virus.
So, if DR
Congo's government wants to roll out immunisation across a wider area, it will
need more supplies.
Those pushing for the use of the new Johnson & Johnson vaccine, had proposed using it to create a protective wall, vaccinating people outside the outbreak zone.
The DR Congo
government has cited concerns about the complexities of using two vaccines
together in the response. It says there is a risk of creating confusion and
increasing mistrust among affected communities.
The fight against the current Ebola epidemic has been marked by community mistrust towards the response.There are also concerns that the new vaccine - which requires two injections 56 days apart - may be difficult to administer in a region where the population is highly mobile, and insecurity is rife.
Source: BBC