Pregnancy test may have spawned deadly frog fungus

A A A

Researchers at South Africa's North-West University think they have traced the spread of the chytrid fungus to a long-standing trade in the African clawed frog.

The frog was used as part of an unusual but effective way of determining pregnancy from the 1930s to the 1960s. The test involved taking the urine of a woman and injecting it into the frog. If the woman was pregnant the hormones in her urine would stimulate ovulation in the frog and within a matter of hours, it would spawn.

Huge numbers of African clawed frogs were exported from South Africa to laboratories carrying out the test all over the world, beginning in the 1930s - the decade in which the first case of the fungus was recorded. They have been traced by examination of preserved frogs in museum collections by Che Weldon, a zoologist at North-West University.

Mr Weldon has researched the spread of the fungus, seen in the Americas, Africa, Australia and Europe, and he thinks the trade could have been responsible. Some of the exported frogs were released or escaped into the wild where it is believed they spread the fungus, which can move quickly through a water system and can jump from one frog species to another. The first case recorded outside South Africa was in Quebec, Canada, in 1961.

Last month, an international team of researchers reported that global warming was helping to spread the deadly skin infection and was triggering the decline of hundreds of species of frogs and toads. It is thought that the average temperatures of many tropical regions, rich in frog and toad species, have shifted to become perfect for the growth of the fungus.

Scientists believe the chytrid fungus is behind the disappearance of the golden toad of Costa Rica, and at least 67 per cent of the 110 species of harlequin frogs from South and Central America over the past 17 years.

What is thought to add weight to the case for an African origin is the fact that the fungus is widespread in southern Africa, but frogs in the region appear to have developed a resistance to it. Mr Weldon said: "Some do succumb, but we have not witnessed the mass die-offs experienced elsewhere."

Infected frogs show an excessive shedding of their skin, and exhibit strange behaviour. Nocturnal species come out in daylight, and river frogs are found above water level among plants.

Last year, it was announced that the chytrid fungus had been found in a colony of escaped American bullfrogs in the south-east of England. The Government's wildlife watchdog, English Nature, has removed more than 11,000 of the infected colony, but it is possible the fungus has infected native British amphibians. Tests are being carried out to discover if the disease has become established in the UK.

PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
Arts and Entertainment
From Mean Girls to Mamet: Lindsay Lohan
theatre
Sport
Nathaniel Clyne (No 2) drives home his side's second goal past Arsenal’s David Ospina at the Emirates
footballArsenal 1 Southampton 2: Arsène Wenger pays the price for picking reserve side in Capital One Cup
News
Mike Tyson has led an appalling and sad life, but are we not a country that gives second chances?
peopleFormer boxer 'watched over' crash victim until ambulance arrived
Arts and Entertainment
Geena Davis, founder and chair of the Geena Davis Institute on Gender in Media
tv
News
i100
Travel
travelGallery And yes, it is indoors
Life and Style
tech
Arts and Entertainment
The Tiger Who Came To Tea
booksJudith Kerr on what inspired her latest animal intruder - 'The Crocodile Under the Bed'
News
i100
Arts and Entertainment
British actor Idris Elba is also a DJ and rapper who played Ibiza last summer
film
News
Alan Bennett criticised the lack of fairness in British society encapsulated by the private school system
peopleBut he does like Stewart Lee
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
iJobs Job Widget
iJobs General

Account Executive/Sales Consultant – Permanent – Hertfordshire - £16-£20k

£16500 - £20000 Per Annum: Clearwater People Solutions Ltd: We are currently r...

KS2 PPA Teacher needed (Mat Cover)- Worthing!

£100 - £125 per day: Randstad Education Crawley: KS2 PPA Teacher currently nee...

IT Systems Manager

£40000 - £45000 per annum + pension, healthcare,25 days: Ashdown Group: An est...

IT Application Support Engineer - Immediate Start

£28000 per annum: Ashdown Group: IT Software Application Support Analyst - Imm...

Day In a Page

Syria air strikes: ‘Peace President’ Obama had to take stronger action against Isis after beheadings

Robert Fisk on Syria air strikes

‘Peace President’ Obama had to take stronger action against Isis after beheadings
Will Lindsay Lohan's West End debut be a turnaround moment for her career?

Lindsay Lohan's West End debut

Will this be a turnaround moment for her career?
'The Crocodile Under the Bed': Judith Kerr's follow-up to 'The Tiger Who Came to Tea'

The follow-up to 'The Tiger Who Came to Tea'

Judith Kerr on what inspired her latest animal intruder - 'The Crocodile Under the Bed' - which has taken 46 years to get into print
BBC Television Centre: A nostalgic wander through the sets, studios and ghosts of programmes past

BBC Television Centre

A nostalgic wander through the sets, studios and ghosts of programmes past
Lonesome George: Custody battle in Galapagos over tortoise remains

My George!

Custody battle in Galapagos over tortoise remains
10 best rucksacks for backpackers

Pack up your troubles: 10 best rucksacks for backpackers

Off on an intrepid trip? Experts from student trip specialists Real Gap and Quest Overseas recommend luggage for travellers on the move
Secret politics of the weekly shop

The politics of the weekly shop

New app reveals political leanings of food companies
Beam me up, Scottie!

Beam me up, Scottie!

Celebrity Trekkies from Alex Salmond to Barack Obama
Beware Wet Paint: The ICA's latest ambitious exhibition

Beware Wet Paint

The ICA's latest ambitious exhibition
Pink Floyd have produced some of rock's greatest ever album covers

Pink Floyd have produced some of rock's greatest ever album covers

Can 'The Endless River' carry on the tradition?
Sanctuary for the suicidal

Sanctuary for the suicidal

One mother's story of how London charity Maytree helped her son with his depression
A roller-coaster tale from the 'voice of a generation'

Not That Kind of Girl:

A roller-coaster tale from 'voice of a generation' Lena Dunham
London is not bedlam or a cradle of vice. In fact it, as much as anywhere, deserves independence

London is not bedlam or a cradle of vice

In fact it, as much as anywhere, deserves independence
Vivienne Westwood 'didn’t want' relationship with Malcolm McLaren

Vivienne Westwood 'didn’t want' relationship with McLaren

Designer 'felt pressured' into going out with Sex Pistols manager
Jourdan Dunn: Model mother

Model mother

Jordan Dunn became one of the best-paid models in the world