Red tape halts mosquito wonder spray

Costs could prevent new repellent more effective than Deet reaching market

A new class of powerful insect repellents that work for up to three times longer than the best existing mosquito repellent has been developed, but may never be commercially produced because of the costly and time-consuming approval process.

The chemicals have been mastered in the laboratory, and rudimentary tests show that they are more effective than Deet, the "gold standard" insect repellent used to protect people against bites and one of the main defences against malaria, which kills an estimated million people each year worldwide.

"Commercial availability of topical repellents can take years and it is a significant investment to achieve that end goal," said Ulrich Bernier, a researcher at the US Department of Agriculture in Gainesville, Florida, who presented the scientific details of the repellents to the national meeting of American Chemical Society in Washington.

"The cost will be several hundred thousand dollars. Once you determine that the repellent works through some screening process, we then have to go through a toxicological hazard evaluation involving numerous toxicological tests. Clearly, the odds are stacked against new repellent products making it to market."

The repellents were discovered by screening the molecular structures of more than 30,000 chemical compounds tested as insect repellents over the past 60 years. Using 11 known compounds, they synthesised 23 new ones, and 10 of these gave about 40 days' protection compared to Deet's 17.5 days when soaked into a cloth worn by volunteers.

Dr Bernier said the work was not the result of simple trial and error but conducted with sophisticated computer programs that could analyse the molecular structure of known repellents to see whether new ones could be synthesised in the laboratory.

The scientists went through the archives of insect repellents dating back six decades. For instance, they checked out 2,000 variants of a compound found in black pepper, which is known for its insect-repellent properties, to see what would work best.

Mosquito repellents must work against female mosquitoes, which have to take blood meals to produce their eggs. The malaria parasite, or plasmodium, infects the mosquito when the insect feeds on an infected host. But the mosquito itself does not become infectious until the plasmodium migrates from the insect's gut to its salivary glands.

Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
News
ebooksNow available in paperback
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: Provisioning Specialist

Negotiable: Recruitment Genius: A Provisioning Specialist is required to join ...

Recruitment Genius: Sales Apprenticeships

£10000 per annum: Recruitment Genius: This is an outstanding opportunity for 1...

Recruitment Genius: Customer Support Engineer

Negotiable: Recruitment Genius: A Support Engineer is required to join a well-...

Recruitment Genius: Customer Services Administrator - Swedish Speaking

Negotiable: Recruitment Genius: This is an exciting opportunity to join an awa...

Day In a Page

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
La Famille Bélier is being touted as this year's Amelie - so why are many in the deaf community outraged by it?

Deaf community outraged by La Famille Bélier

The new film tells the story of a deaf-mute farming family and is being touted as this year's Amelie
10 best high-end laptops

10 best high-end laptops

From lightweight and zippy devices to gaming beasts, we test the latest in top-spec portable computers
Michael Carberry: ‘After such a tough time, I’m not sure I will stay in the game’

Michael Carberry: ‘After such a tough time, I’m not sure I will stay in the game’

The batsman has grown disillusioned after England’s Ashes debacle and allegations linking him to the Pietersen affair
Susie Wolff: A driving force in battle for equality behind the wheel

Susie Wolff: A driving force in battle for equality behind the wheel

The Williams driver has had plenty of doubters, but hopes she will be judged by her ability in the cockpit
Adam Gemili interview: 'No abs Adam' plans to muscle in on Usain Bolt's turf

'No abs Adam' plans to muscle in on Usain Bolt's turf

After a year touched by tragedy, Adam Gemili wants to become the sixth Briton to run a sub-10sec 100m
Calls for a military mental health 'quality mark'

Homeless Veterans campaign

Expert calls for military mental health 'quality mark'
Racton Man: Analysis shows famous skeleton was a 6ft Bronze Age superman

Meet Racton Man

Analysis shows famous skeleton was a 6ft Bronze Age superman
Garden Bridge: St Paul’s adds to £175m project’s troubled waters

Garden Bridge

St Paul’s adds to £175m project’s troubled waters
Stuff your own Christmas mouse ornament: An evening class in taxidermy with a festive feel

Stuff your own Christmas mouse ornament

An evening class in taxidermy with a festive feel
Joint Enterprise: The legal doctrine which critics say has caused hundreds of miscarriages of justice

Joint Enterprise

The legal doctrine which critics say has caused hundreds of miscarriages of justice
Freud and Eros: Love, Lust and Longing at the Freud Museum: Objects of Desire

Freud and Eros

Love, Lust and Longing at the Freud Museum