Microbe of the Month: A malevolent beast outfoxed: Genetic engineering could be the means of at last ridding Europe of rabies, says Bernard Dixon

MEMBER states of the European Community are about to fail to meet another deadline. They are supposed to have eliminated the rabies virus from the wildlife in their countries by the end of the year, but pockets of infection remain.

The turmoil in Eastern Europe has not helped; for instance, collaboration between Italy and the former Yugoslavia in exterminating rabies from their borderlands has all but broken down. It seems, therefore, that the precautions, including quarantine, that have kept Britain virtually free of rabies since the First World War will need to remain in force a little longer.

The eradication campaign now rests in part on a genetically engineered vaccine that has been successful in eliminating the virus from foxes in a large part of Belgium. Alarmists may associate genetic engineering with unspeakable horrors, but it is on the verge of clearing from an entire continent one of humankind's most loathsome infections.

The rabies virus is a lethal and malevolent microbe. In one recent case, a man in Texas was bitten on the right index finger by a bat. More than a month later, his hand became weak and he sought medical attention. Six days of increasing pain and torment followed.

Before he slipped into a coma and died, the man suffered hallucinations and high fever, continuous drooling, frequent spasms in the face, mouth and neck, severe breathlessness and difficulty in swallowing.

Although humans can be protected by a series of injections, even after being bitten by a rabid animal, the inoculations are expensive and can have side-effects. And many people are immunised unnecessarily, not knowing whether the animal concerned was in fact carrying the disease.

The main eradication effort in Europe is focused on foxes. The first strategy was to cull them, but measures such as gassing, poisoning and trapping only partially achieved the target.

The alternative approach has been immunisation. An injectible vaccine, of the sort used to protect domestic animals, is hardly practical. Researchers therefore developed weakened strains of the rabies virus that, when taken by mouth, trigger disease-fighting antibodies, without causing the disease itself.

Baits carrying these vaccines were used first in Switzerland, then in France and Germany.

However, two worries have emerged: these live, attenuated viruses retain some degree of virulence towards rodents; and they could, in theory, regain their virulence against foxes and other animals.

This prompted researchers at Transgene SA, in Strasbourg; Rhone Merieux, in Lyon; and the University of Liege to investigate the feasibility of a genetically engineered vaccine lacking such drawbacks. Instead of trying to modify the virus, the genetic engineers harnessed only the part of it that induces the protective antibodies and cannot cause the disease. They selected one component of the virus's protein coat and transferred the gene - a unit of hereditary material - responsible for producing this protein into vaccinia, the virus formerly used to immunise us against smallpox.

The hope was that this hybrid virus would grow in the cells of the fox, making the rabies protein and thereby provoking the animal to make antibodies against the disease.

It worked well. After helicopters had dropped 25,000 baits carrying the vaccine over a 2,200sq km area of southern Belgium, 81 per cent of foxes later sampled had become immune to rabies. And as predicted from a model of the percentage immunity required to block transmission of the virus, the disease disappeared accordingly.

The continental rabies epidemic that necessitated the familiar posters and quarantine measures at British ports began in Poland during the Second World War. Now, thanks to the new vaccines, what once appeared to be an inexorable movement towards the coast of France has been arrested, and the UK and Ireland may soon be free of this hideous threat from across the Channel.

(Photograph omitted)

Start your day with The Independent, sign up for daily news emails
Voices
Barn owls are among species that could be affected
charity appeal
News
Sarah Silverman (middle) with sister Reform Rabbi Susan Silverman (right) and sister actress Laura Silverman (left) at Jerusalem's Western Wall for feminist Hanuka candle-lighting ceremony
peopleControversial comedian stages pro-equality Hanukkah lighting during a protest at Jerusalem's Wailing Wall
Arts and Entertainment
The Bach Choir has been crowned the inaugural winner of Sky Arts’ show The Great Culture Quiz
arts + ents140-year-old choir declared winner of Sky Arts' 'The Great Culture Quiz'
Sport
After another poor series in Sri Lanka, Alastair Cook claimed all players go through a lean period
cricketEoin Morgan reportedly to take over ODI captaincy
PROMOTED VIDEO
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Finance Director

£65000 - £80000 per annum: Recruitment Genius: Finance Director required to jo...

Recruitment Genius: Medico-Legal Assistant

£15000 - £25000 per annum: Recruitment Genius: This is a unique opportunity fo...

Ashdown Group: (PHP / Python) - Global Media firm

£50000 per annum + 26 days holiday,pension: Ashdown Group: A highly successful...

The Jenrick Group: Quality Inspector

£27000 per annum + pension + holidays: The Jenrick Group: A Quality Technician...

Day In a Page

Homeless Veterans appeal: 'You look for someone who's an inspiration and try to be like them'

Homeless Veterans appeal

In 2010, Sgt Gary Jamieson stepped on an IED in Afghanistan and lost his legs and an arm. He reveals what, and who, helped him to make a remarkable recovery
Could cannabis oil reverse the effects of cancer?

Could cannabis oil reverse effects of cancer?

As a film following six patients receiving the controversial treatment is released, Kate Hilpern uncovers a very slippery issue
The Interview movie review: You can't see Seth Rogen and James Franco's Kim Jong Un assassination film, but you can read about it here

The Interview movie review

You can't see Seth Rogen and James Franco's Kim Jong Un assassination film, but you can read about it here
Serial mania has propelled podcasts into the cultural mainstream

How podcasts became mainstream

People have consumed gripping armchair investigation Serial with a relish typically reserved for box-set binges
Jesus Christ has become an unlikely pin-up for hipster marketing companies

Jesus Christ has become an unlikely pin-up

Kevin Lee Light, aka "Jesus", is the newest client of creative agency Mother while rival agency Anomaly has launched Sexy Jesus, depicting the Messiah in a series of Athena-style poses
Rosetta space mission voted most important scientific breakthrough of 2014

A memorable year for science – if not for mice

The most important scientific breakthroughs of 2014
Christmas cocktails to make you merry: From eggnog to Brown Betty and Rum Bumpo

Christmas cocktails to make you merry

Mulled wine is an essential seasonal treat. But now drinkers are rediscovering other traditional festive tipples. Angela Clutton raises a glass to Christmas cocktails
5 best activity trackers

Fitness technology: 5 best activity trackers

Up the ante in your regimen and change the habits of a lifetime with this wearable tech
Paul Scholes column: It's a little-known fact, but I have played one of the seven dwarves

Paul Scholes column

It's a little-known fact, but I have played one of the seven dwarves
Fifa's travelling circus once again steals limelight from real stars

Fifa's travelling circus once again steals limelight from real stars

Club World Cup kicked into the long grass by the continued farce surrounding Blatter, Garcia, Russia and Qatar
Frank Warren column: 2014 – boxing is back and winning new fans

Frank Warren: Boxing is back and winning new fans

2014 proves it's now one of sport's biggest hitters again
Jeb Bush vs Hillary Clinton: The power dynamics of the two first families

Jeb Bush vs Hillary Clinton

Karen Tumulty explores the power dynamics of the two first families
Stockholm is rivalling Silicon Valley with a hotbed of technology start-ups

Stockholm is rivalling Silicon Valley

The Swedish capital is home to two of the most popular video games in the world, as well as thousands of technology start-ups worth hundreds of millions of pounds – and it's all happened since 2009
Did Japanese workers really get their symbols mixed up and display Santa on a crucifix?

Crucified Santa: Urban myth refuses to die

The story goes that Japanese store workers created a life-size effigy of a smiling "Father Kurisumasu" attached to a facsimile of Our Lord's final instrument of torture
Jennifer Saunders and Kate Moss join David Walliams on set for TV adaptation of The Boy in the Dress

The Boy in the Dress: On set with the stars

Walliams' story about a boy who goes to school in a dress will be shown this Christmas