THE VIRGINIAN-PILOT
Copyright (c) 1995, Landmark Communications, Inc.
DATE: Tuesday, December 26, 1995 TAG: 9512260029
SECTION: FRONT PAGE: A1 EDITION: FINAL
SOURCE: BY MARIE JOYCE, STAFF WRITER
LENGTH: Long : 131 lines
The rabbits are dying by the hundreds of thousands in Australia, felled by a virus that escaped from a research facility and is rampaging across the country.
The Aussies, who were planning to use the virus as a rabbit pesticide, are cheering.
Here in Hampton Roads, one scientist worries that they've made a mistake.
Dr. David O. Matson, an expert in the type of virus called calicivirus, has added his voice to a scientific debate - via Internet, fax and the press - that's raising tempers in both hemispheres.
Matson, who has been in contact with scientists and government officials involved in researching the virus and has been interviewed by a newspaper in Melbourne, is critical of the biological warfare used to rid Australia of its rabbit population. The virus could jump species, he says, and while it's not likely to infect humans, the whole adventure is risky.
``You can make a bet that it probably is safe,'' he said. But ``we don't know enough to know that it's safe.'' Matson works at Norfolk's Center for Pediatric Research, a joint project of Eastern Virginia Medical School and Children's Hospital of The King's Daughters.
To understand what happened, one must understand how much Australians hate rabbits.
The rabbit is a foreign invader, imported in 1859 by a man who wanted to start a small population for hunting.
The descendants of the original 12 have grown into a menace several hundred million strong, wiping out native species, threatening agriculture, stripping the land and causing soil erosion.
Veterinarian Keith Murray, a Scotland native who had lived in the United States for years, said it took awhile to understand the depth of Australians' hatred when he joined a program there to control the rabbit population.
``It's almost like a core value, a cultural thing,'' he said. ``Parts of Australia look like the surface of the moon because of those rabbits. They're seen by Australians as being lower than vermin, worse than rats.''
In the 1950s, the country imported a virus that causes a fatal disease, myxomatosis, in rabbits. But the population is developing immunity to it. Scientists are working on genetic alterations to the myxoma virus that would sterilize the rabbits, but that is years off.
In the meantime, they turned to the calicivirus. Rabbit calicivirus (kal-EE-see-virus), identified in the 1980s, has swept through Europe, killing millions of rabbits. The virus doesn't kill rabbit species native to the United States.
About six years ago, a scientific group hired by Australia and New Zealand, which has the same problem, imported a strain from Eastern Europe and began tests to make sure the virus wouldn't hurt other species like kangaroos. The governments were hoping to start releasing the virus in 1998.
The unplanned outbreak started with a group of test rabbits isolated on an island off Australia's southern coast. Apparently flies picked up the virus on their mouth parts from rabbit secretions, said Nicholas Newland, who heads the joint Australia-New Zealand rabbit calicivirus project. The flies probably got caught in a weather system that blew them inland.
That was about about three months ago. Since then, the virus has spread across the continent. Investigators are still counting the toll, but in some areas, the bug reportedly has killed 95 percent of the rabbits. New Zealand is considering speeding up its program to release the virus. For the most part, Australians have applauded the unplanned invasion.
But Matson, and colleague Alvin W. Smith, a veterinarian from Oregon State University, are not so thrilled.
Most types of calicivirus can infect humans, said Matson. Some types cause gastrointestinal problems, such as vomiting and diarrhea. One type of calicivirus causes hepatitis E, a sometimes-fatal disease that's especially dangerous to pregnant women; this type is rare in the United States.
Rabbit calicivirus, the one spreading in Australia, is not known to attack humans. Scientists in Australia, who have been studying it for years, say rabbit calicivirus disease is so prevalent in many other countries that transmission to humans would have been discovered by now, if it were possible, Murray said.
``There's not a single scrap of evidence that rabbit calicivirus will change and jump species,'' Murray said. ``In fact, there's some evidence against that.''
But Matson isn't so sure. Suppose there were episodes of human infection that didn't get reported?
``There must be some barrier'' to human infection, he said, ``But we don't know how strong that barrier is.''
The huge concentration of virus in the hordes of infected Australian rabbits could overwhelm that barrier, he said.
``My gut feeling is (transmission to humans) probably doesn't happen. But I wouldn't want to be in the position of being the one who released something when it happens for the first time.''
Matson's colleague in Oregon, veterinarian Alvin Smith, has been more emphatic. Smith has said the virus could infect and damage Australia's and New Zealand's livestock industries.
``Australia has a massive, extremely dangerous situation on their hands,'' he said in a release.
His claims have sparked angry denunciations from Australian officials. Matson apparently hasn't made them angry.
``We've learned some specific and useful information from Dr. Matson,'' said Murray. ``I hope Dr. Matson has learned a hell of a lot . . . that he wasn't aware of either.''
And there's certainly no regret among Australian officials, even though the surviving rabbit population eventually may develop an immunity to calicivirus and bounce back. The virus buys Australians time to look for more solutions, said Newland.
As for the American criticisms: ``To have this sort of thing come up right now really hasn't been all that helpful.'' MEMO: THE HATED HARE
Rabbits were brought to Australia in 1859, but their population has
swelled to several hundred million.
A virus to control their numbers has been used since the 1950s, but
the rabbits are developing an immunity to it.
A new virus, still undergoing testing, was spread by mistake. It has
killed up to 95 percent of the rabbits in some places.
FOR DETAILS
The Commonwealth Scientific and Industrial Research Organisation, the
group that has conducted research into the rabbit calicivirus for the
governments of Australia and New Zealand, has a detailed Internet
homepage about the outbreak. It can be reached at:
http://commsun.its.csiro.au/communication/rabbits/rabbits.htm
or
http://www.csiro.au/communication/rabbits/rabbits.htm
ILLUSTRATION: ASSOCIATED PRESS photo
Rod Roxborough, a marksman who makes a living killing rabbits, is
one of the few Australians troubled by the virus-inflicted deaths of
millions of them. Rabbits have wiped out native species, threatened
farming and stripped the land.
by CNB