A disease caused by a highly contagious fungus has wiped out as many as 200 species of frog worldwide since the 1970s, and pushed many more to the brink of extinction.

But researchers now believe that some frogs may be developing a resistance to the deadly chytrid fungus.

When chytridiomycosis wiped through a biodiversity hotspot called El Cope in Panama in 2004, scientists said the spread was so rapid that, in places, dead frogs littered the forest floor.

In the study published today in Science, researchers have documented the recovery of nine frog species in three regions of Panama, including El Cope, and have observed infected frogs showing no ill effects from the fungus.

"We know that immediately after the outbreak, [the frogs] seemed to be completely gone," lead author Jamie Voyles from the University of Nevada said.

"But in some locations they have recovered remarkably well and they're infected with the pathogen."

As part of the study, the researchers also exposed captive frogs to chytrid fungus. Those frogs were from a breeding stock taken into captivity before the outbreak of chytridiomycosis, and therefore had no chance to develop immunity.

All captive frogs died with 48 days of exposure.

They also ran tests to compare the potency of the disease between a 2004 sample and a 2012-13 sample.

By combining this data, they were able to establish whether the disease was getting weaker, or the frogs were become more resilient.

"At the outset, I actually thought there was going to be changes in the pathogen, but I was wrong," Dr Voyles said.

"It turns out that the pathogen is still as deadly today in Panama as it was about a decade ago."

Australian frogs needing 'urgent conservation intervention'

Scientists at the time of the Panama pandemic said dead frogs littered the forest floor. ( Supplied: Jamie Voyles )

Six Australian frog species haven't been observed in the wild since the disease was detected here in 1993, and the CSIRO say several Australian species are currently needing "urgent conservation intervention" to halt their decline.

Infected frogs can typically be found sitting in the open, emaciated, with peeling skin and showing signs of lethargy.

The fungus is able to use the frogs' natural process of skin shedding to carry out its lifecycle, according to James Cook University (JCU) scientist Dr Lee Berger, who was not involved with the study.

"It [gets] inside the cells of the epidermis and as the cells turn over and are shed … the mature fungus gets carried to the surface [where] it releases the infected spores to the water," Dr Berger said.

"Sodium and potassium in the [frogs'] blood goes down really low [and they] have a heart attack."

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She first positively identified chytridiomycosis in Australia in 1997.

"People were looking at pollution and climate change and other things," she said.

"But frogs were disappearing within months, people were seeing [populations] crash within months, so it made sense that it was a fatal disease."

The fungus is mostly limited to moist and cooler environments like rainforests, and hasn't yet been detected in areas like Kakadu. However a number of populations have been hit in North Queensland's wet tropics.

Scientists have successfully translocated species to regions where the fungus doesn't occur, such as the armoured mistfrog, which was reduced to a single population along a 4-kilometre stretch of stream in north-east Queensland.

Researchers say modern strains of the fungus are genetically similar. ( Supplied: Douglas Woodhams )

And there is a captive breeding population of Australia's iconic corroboree frog, which Dr Berger is hoping to begin genetic work on to improve its resistance to chytridiomycosis.

"If [resistance] turns out to be just a few genes, the quickest way is to do transgenics — to just insert those key genes into other frogs," she said.

But more iconic species will be lost if intervention programs don't get support, Dr Voyles warned.

"The study really underscores the importance of continuing to monitor these populations and to do research and make an effort in terms of conservation," she said.