Mers Vaccine a Step Closer

Mers Vaccine  a Step Closer Mers Vaccine  a Step Closer

An effective vaccine to protect against the Mers virus is a step closer, a report in the journal Science suggests.

European scientists genetically modified a version of the smallpox vaccine to display Mers virus protein on its surface.

The vaccine was able to protect camels - the animal reservoir for the virus - from developing symptoms of the disease.

Experts hope the vaccine will stop the virus spreading in camels and also protect humans at risk from infection.

Mers-coronavirus infection of humans was first described in Saudi Arabia in 2012. Since then there have been more than 1,600 reported cases. More than a third of reported infections have resulted in death, reports BBC News website.

Individuals with other illnesses - such as diabetes, long term lung disease or kidney failure - are particularly prone to developing life-threatening symptoms.

Virus spread is limited to people who have close contact with those who are infected, such as family members and healthcare workers.

Infections have been reported in 26 countries with the epicenter of the outbreak in the Arabian Peninsula.

There are no treatments for Mers but scientists are trying to develop an effective vaccine.

Prof. Bart Haagmans, based at the Erasmus Medical Center in the Netherlands has been busy developing and testing vaccines in camels.

  Lumpy Problem

Dromedary camels, which are bred and raised for their milk and meat and for racing, are thought to be the initial source for human outbreaks.

The virus is particularly prevalent in juvenile camels, where infection results in mild symptoms that are similar to a common cold. It is thought to pass to humans when they have contact with an infected camel’s body fluids.

Circulation of Mers in camels poses a serious risk to human health and many scientists are worried that the virus might mutate to become better adapted to human spread.

Vaccines train the human immune response to recognize a virus and to wipe it out before it can infect or do any harm.

There are two arms to this protection - antibodies and killer cells.

Antibodies are proteins found in human blood and in body fluids like mucus and saliva and these attach to the virus and stop it infecting.

Killer cells, as the name suggests, track down virus infected cells and kill the cell before new virus is released.

Some vaccines raise antibodies, some produce killer cells and some raise both. Prof Haagmans believed that the best way to control Mers was to develop a vaccine that produced both.

So he and a team of scientists drawn from the Netherlands, Spain and Germany, genetically engineered a pox virus called Modified Vaccinia Ankara -MVA - to display Mers virus spike protein on its surface.

MVA was used to eradicate smallpox and is currently being used to develop vaccines to a variety of viruses like influenza, Ebola and hepatitis C. Importantly it can produce antibodies and killer cells.