April 1, 2014

expert reaction to Ebola virus outbreak in Guinea

Further comments about the disease which has now spread beyond Guinea’s borders.

Prof Jonathan Ball, Professor of Molecular Virology, University of Nottingham, said:

“The number of current cases of Ebola infection in Western Africa is not unprecedented – there have been larger outbreaks, but we may yet see a further increase in the number of people affected by this current outbreak in Guinea. What is unusual this time is how widespread the outbreak is, most likely due to people travelling, although numerous sparks – spillovers from animals reservoirs – could also be responsible.

“That Ebola has found its way to densely populated urban areas is a concern – large numbers of people living at high density really helps infectious diseases spread.

“Ebola is spread following close contact. We don’t really understand the transmission process but we know that body fluids are a major source of virus. So anyone infected or with a recent past infection can spread the virus – there is evidence that men who’ve recovered from infection can continue to shed virus in their semen for many weeks

“It’s worth remembering that this isn’t the most infectious virus. Those most at risk are close contacts and healthcare workers, but basic precautions – good hygiene and use of personal protective equipment – are effective in stopping the spread.”

Dr Ben Neuman, a virologist at the University of Reading, said:

“Ebola virus is one of the things that keep public health officials up at night.  If this virus was able to spread between people more easily than it currently does, it would have the potential to be more deadly than the black plague.  But currently it is not.  Ebola normally needs to be in the bloodstream in order to grow, and it is thought to arrive there via the surface of the eye, or by attaching to cells lining the throat.  So, like other bloodborne infections, Ebola does not spread easily between people.  Other different viruses that spread more easily usually spread through contaminated water, or by tiny droplets in the air.  However, until we understand more about why the Ebola virus grows in some cells and not others, it is difficult to predict how difficult it would be for the virus to change the way it spreads.

“Ebola virus is fragile and does not survive long outside the body, so the best protection is to avoid direct contact with bodily fluids from infected people.  While it is possible in theory to transmit Ebola fever sexually, usually the virus is spread to family members and hospital staff who tend the sick.  The other common route for infection is at public open casket funerals of Ebola victims, which have now been banned in Guinea.

“The real worry though is that the virus has been found in the capital, Conakry, a city with a population density of close to 10,000 per square kilometre.  An Ebola outbreak there could lead to a humanitarian disaster.

“While nothing can be done at this time to root out the virus at its source, likely in bats, measures such as banning bushmeat sales and public funerals have been used successfully to combat past Ebola outbreaks.”