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1) Scientists Search for Human Hand Behind Outbreak of Jungle Virus [WSJ] -- 06.19.03
2) Deadly New Virus Draws Experts to "Hot Zones" [National Geographic Today] -- 01.21.03
3) Bats to blame for Nipah virus deaths [Straits Times] -- 05.13.02
4) World Health Organization - Nipah Virus Factsheet [World Health Organization] -- 09.01.01
5) Nipah in the wilderness [Star - Malaysia] -- 04.10.00
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PAGE ONE
CONTAINING THE OUTBREAK
Scientists Search for Human Hand Behind Outbreak of Jungle Virus
By PETER FRITSCH
Staff Reporter of THE WALL STREET JOURNAL
IPOH, Malaysia -- Thick jungle vegetation has taken over the concrete pens that once held thousands of pigs at the Leong Seng Nam farm. Rusting tractors bake in their tracks under a blistering sun. Only the lush mango and jackfruit trees appear unchanged from four years ago, when the farm and most everything on it were abandoned in terrific haste.
At the main gate, a sign bearing the silhouette of a man shooting a trespasser warns that no one should return: "We accept no visitors in view of the outbreak of swine disease."
But an ambitious group of outsiders has come back -- to ground zero of a frightening viral outbreak in 1998 and 1999. The previously unknown "Nipah" virus, named for the Malaysian village where it was first isolated, leapt from beast to man and killed both at a torrid rate. Then it disappeared back into the surrounding forests and limestone cliffs. The virus decimated Malaysia's fast-growing pork industry and killed 40% of the 257 people who caught it. So deadly is Nipah that the U.S. lists it among potential bioterrorism agents.
As governments begin to declare cautious victory over severe acute respiratory syndrome -- a disease that, like HIV, Ebola and Nipah is believed to have jumped from an animal host to humans -- some scientists are turning their attention to a question asked all too infrequently once deadly viral outbreaks have been contained: Where did that come from?
One such group of investigators is digging in at Ipoh, with an unconventional, multidisciplinary approach involving virologists, ecologists, zoologists, botanists and even agronomists familiar with pig-farming techniques.
Organized by the Consortium for Conservation Medicine in Palisades, N.Y., and equipped with a $1.4 million grant from the National Institutes of Health, the team of scientists will test over the next four years a compelling, if complex, theory of Nipah's emergence. It goes like this: The burning of over 12 million acres of virgin forest in Borneo and Sumatra in the fall of 1997 cast an extreme haze over a huge swath of Southeast Asia for months. That haze blocked sunlight, reducing the ability of trees to flower and bear fruit. This caused giant bats to travel great distances in search of sustenance. They settled on fruit trees fertilized with the manure of pigs on huge Malaysian farms cut out of the forests where the so-called flying foxes roost.
Somehow, the theory goes, the bats then passed the virus to the pigs who -- because of physiological and genetic similarities to humans -- amplified its potency and began infecting people in contact with them.
To some conservationists and scientists, there would be a dark poetic justice in a disease passed to man from an animal endangered by man's encroachment on its treetop environment. "In the case of almost every emerging disease, complex human changes to the environment drive emergence," says Dr. Peter Daszak, a parasitologist and executive director of the consortium that organized the study. "Nipah appears to be a case of the bats getting some payback."
The results of the Nipah investigation could be a key to understanding the many variables involved in sudden viral outbreaks.
They could also have implications for environmental policy. If human intervention in nature is shown to have triggered the deadly epidemics, then the arguments for protecting fragile ecology suddenly become much more palpable than the desire to preserve rare landscapes or endangered species.
Pteropus vampyrus
It's far from certain that man brought on Nipah, or any of the other sudden viral scourges of recent years. And determining conclusively how a virus progresses among different species is extraordinarily difficult.
"There is always a massive knowledge gap in understanding what drives a virus that evolved over thousands of years and co-exists peacefully with one animal to jump and eventually come into contact with man," says Malaysian scientist Dr. Chua Kaw Bing, the first researcher to trace the Nipah virus to enormous endangered fruit bats, known locally as flying foxes.
In the case of SARS, researchers in Hong Kong have identified the civet cat, a relative of the raccoon, as one animal player in the spread of the virus. But they have also found SARS coronavirus antibodies in a Chinese ferret badger and a raccoon, meaning researchers are still a long way from establishing whether the civet is the virus's natural "reservoir" or just one link in a much more complex ecological chain.
Pinning down the animal source of the terrifying Ebola virus has also been difficult. In 1994, the first appearance of Ebola in 15 years occurred in a Swiss researcher on the Ivory Coast. Investigators quick to the scene thought they could trace the virus from chimpanzees dying of the disease to their prey, red colobus monkeys, which also die of the virus. World Health Organization researchers armed with a $250,000 grant undertook an ambitious study to find Ebola's natural host.
But even after collecting thousands of insects, birds and mammals that interact with the monkeys, the Ebola reservoir was as elusive as ever. "After four years, our agencies got fed up and our funding disappeared," says Francois Meslin, the WHO's top expert on diseases acquired from animals.
Determining the role of the flying foxes -- known scientifically as pteropus vampyrus -- will be critical to charting the origins of the Nipah virus. The bats are the world's largest, with the Malayan variety boasting a five-foot wingspan. Local hunters shoot and eat them. In Cambodia, they are prized as aphrodisiacs, and the bats are used as good-luck talismans in Filipino wedding ceremonies.
The bats are also Nipah's most likely natural host, since they have natural antibodies that protect them from the virus. As flying mammals common across the region, they also -- at least in theory -- make a highly mobile carrier of disease that could cross over to human populations.
The scientific team organized by the Consortium for Conservation Medicine, a joint venture between the Harvard Medical School's Center for Health and the Global Environment, Tufts University's School of Veterinary Medicine, the Wildlife Trust and the U.S. government's National Wildlife Health Center, starts with a working theory that the Nipah virus transmitted from bat to pig as a result of the flying foxes' messy eating habits.
After sucking the juice from fruit, they spit out pulp and drop half-eaten fruit to the ground. Scientists believe this is what they did while feeding in trees overhanging the pig pens at the Leong Seng Nam farm and other farms in Ipoh, delivering a lethal dose of virus-laden saliva to voracious hogs.
Pigs can pick up pathogens from a natural host and render them more infectious before passing them on to humans. In the case of Nipah, pigs developed encephalitis and a "one-mile cough" -- so called because their violent hacking could be heard at great distances -- before quickly dying. Men working with the swine then picked up the disease. More than 100 people died in Malaysia. Humans apparently don't infect each other with Nipah, so a massive culling of 1.1 million pigs stopped its spread.
The linchpin of the theory is that virus-carrying flying foxes can migrate great distances -- something that has never been studied due to the nocturnal animal's remote and vast range.
The scientists hope to outfit a handful of flying foxes with solar-powered radio collars that can last four years -- if the bats don't shake the $5,000 devices. Such radio-tracking in Australia has shown that some bats will periodically travel up to 375 miles.
But the Malaysian team first has to catch them. "Very difficult," says Azizi bin Mohammed Yatim, a bat catcher with Malaysia's Veterinary Research Institute in Ipoh. On a recent nighttime trip into the jungle, Mr. Azizi and his crew struggled to apprehend even small bats in fishing nets set up around fruit trees. One small cave-dwelling bat the size of a chipmunk let out a series of terrific squeals while biting repeatedly at a handler's welding gloves.
"You can imagine the time we'll have with vampyrus," says Kevin Olival, a 27-year-old working on his Ph.D. at Columbia University. Mr. Olival is on hand to perform sophisticated genetic tracing of the bats. He hopes this will prove that flying foxes migrate over great distances and across water.
Mr. Olival hopes to take "wing punches" from captured flying foxes -- 3-millimeter holes cut from the bat's wing (they grow back). Then, he will use satellite location technology and genetic data extracted from those punches to track the movement of bats from Thailand down through Sumatra. If a "marker" in the DNA sequence of a bat in Malaysia, for instance, matches that of a bat in Sumatra, one can assume the bat populations move and mix -- or that flying foxes are all part of one huge population.
To prove the thesis of an environmental trigger to the Nipah virus, the team must also establish whether the forest fires of 1997 could really have caused atmospheric conditions disruptive enough to so alter the migratory movements of the giant bats.
As the dry, summer haze season approaches in Southeast Asia, another member of the team, 26-year-old Malaysian graduate student Chong Kwai Hoe, will use satellite images to track and map smoke from forest fires. He will then criss-cross Malaysia's ubiquitous oil palm plantations, taking readings on the effect of smoke on the fruit production of palm trees -- a proxy for all species of fruiting trees.
Other scientists will study flying-fox blood and urine -- even the ticks and fleas they carry. Then they will collate and compare what they find with studies under way in Australia of bats bearing the Hendra virus -- another killer closely related to Nipah. They also will go to India to study a recent outbreak of a deadly virus in Uttar Pradesh state similarly thought to have come from fruit bats. That virus responds to the same antibody test as Nipah.
A separate Japanese team, meanwhile, is in Malaysia analyzing pig tissue samples from as far back as 1994. If they find the Nipah virus, the thesis that extreme haze in 1997 ignited the outbreak will have to be reconsidered.
http://online.wsj.com/article/0,,SB10559743167269800,00.html?mod=todays%5Fus%5Fpageone%5Fhs
Write to Peter Fritsch at [email protected]
Updated June 19, 2003
COPYRIGHT THE WALL STREET JOURNAL
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Deadly New Virus Draws Experts to "Hot Zones"
Bijal P. Trivedi
National Geographic Today
January 21, 2003
This summer, a team of virus hunters will journey to Australia, Malaysia, India, Sumatra and Thailand to explore what they call "hot zones"�sites where deadly new diseases have emerged.
In all the locations the common enemy is the Nipah virus, or a relative. The Nipah broke out in Malaysia in 1998. Now known to be transmitted by a fruit bat, it first killed thousands of pigs. Within weeks, it spread to people. The final human death toll was more than 110.
Now the virus hunters are on the move to learn why and how the Nipah virus strikes. Their research can help head off not only the Nipah but also other virulent diseases that break out suddenly to plague man and beast.
To curtail the initial Nipah outbreak, the Malaysian government slaughtered 1 million pigs�decimating the local swine industry.
"We want to know what changes drove this virus to emerge in the first place," says Peter Daszak, executive director of the Consortium for Conservation Medicine, a research group that focuses on emerging diseases, based at Wildlife Trust in Palisades, New York. "What conditions allowed this virus to jump from bats to pigs to people?"
The summer's investigations take on a new urgency because of recent reports that the Nipah virus, and other similar ones, may be more widespread in Southeast Asia than anybody recognized.
A Quick Killer
The National Institute of Health has awarded $1.4 million to the Consortium to fund further research on the Nipah virus and the related Hendra virus, also carried by fruit bats.
Fruit bats range from Southeast Asia all the way to Africa, raising concerns that different species may harbor more dangerous variants of the Nipah. "There are probably related viruses all over the area with the potential not just to cause outbreaks in agricultural stock but also to cause serious disease in humans," says Stephen Morse, a viral epidemiologist at Columbia University in New York, director of Columbia's Center for Public Health Preparedness and author of the book "Emerging Viruses."
In Malaysia, Nipah's host, or "reservoir," is a large fruit bat, Pteropus vampyrus, with a body the size of a small puppy and a 5-foot wingspan.
Hume Field, a wildlife veterinarian at the Queensland Department of Primary Industries, in Brisbane, Australia, who was in Malaysia in 1999 during the outbreak, helped determine that local fruit bats carried the disease.
Field and another colleague netted more than 300 bats and sent blood samples to labs in Australia�they tested positive.
Nipah replicates fast in pigs. Passage to the lungs brings on a "terrible rasping cough," hemorrhaging and raging pneumonia, Field says. When the virus hits the brain, it kills quickly.
Environmental Change, Reservoirs of Disease
Humans get the virus from contact with the infected pigs. Flu-like symptoms can lead to encephalitis and catatonia. In 40 percent of cases the disease is fatal.
Nipah's emergence in 1998 may have derived from the interaction of man and nature, according to Daszak and researcher Jonathan Patz, director of the Program on Health Effects Of Global Environmental Change at Johns Hopkins University in Baltimore.
The researchers envisioned a scenario where an El Ni�o caused severe dry conditions. Fires that people had set to clear land burned out of control.
The smoke and haze stunted fruit development in the shrinking forests and forced the bats to migrate to places outside their usual habitat�like the forest outskirts, near neighboring pig farms.
On many farms, animal pens mingle with orchards. The researchers believe that fruit bats may have contaminated fruit that then fell into the pigpens.
"It's a really unnatural set of circumstances that has brought pigs in close contact with fruit bats," says Daszak. "The real tragedy is that Pteropus vampyrus is already endangered. Now these viruses make it even more unwanted."
"It's an extremely complex situation," says Patz. "These environmental landscape changes like logging and burning are global in scale, and have the potential to bring together people, wildlife and reservoirs of diseases in ways we couldn't anticipate."
Researchers understand little about the link between ecological disruption and disease. The field requires a multidisciplinary approach. The Consortium, for example, draws on information from ecologists, epidemiologists, physicians, public-health specialists, veterinarians, virologists and wildlife specialists.
"With increasing globalization there are more opportunities to spread an otherwise geographically contained disease," Morse says. "A good surveillance system is required to prevent such outbreaks."
http://news.nationalgeographic.com/news/2003/01/0121_030121_tvvirushunter.html
Copyright National Geographic
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MAR 13, 2002
Bats to blame for Nipah virus deaths
By Sharmilpal Kaur
Straits Times
NOW it is certain: Flying foxes spread the Nipah virus to pigs in the 1999 outbreak that killed 100 pig farmers in Malaysia and an abattoir worker in Singapore.
They have been conclusively identified as the villains by Dr K.B. Chua, a microbiologist and paediatrics professor at the International Medical University in Malaysia.
He presented his findings yesterday at the 10th International Congress of Infectious Diseases.
The Nipah outbreak led to more than 800,000 pigs in Malaysia being culled and Singapore banning the import of live pigs since March 1999. p> Dr Chua told The Straits Times that climate change and the El Nino weather phenomenon of 1998 caused the outbreak indirectly.
Flying foxes, or fruit bats, are natural reservoirs of the Nipah virus and are linked to a related bug, the Hendra virus, which infects cats, horses and pigs via the bats' urine.
Normally, flying foxes live deep in the jungle, feeding off succulent fruit like jambu air and mango.
But, during 1997-1998, El Nino brought drought and dry weather to the region. That led to massive forest fires and the haze that shrouded the region for months.
Referring to the drought and the haze, Dr Chua said: 'This combined effect has been shown to stop some trees from flowering.
'No flowers means no fruits, so the bats migrate to an area where there are fruits and nectar.'
The flying foxes were forced to venture out to orchards, some of which were near pig farms.
They passed the virus on to pigs via their urine, as well as their saliva in the half-eaten fruit that fell to the ground and was then eaten by the pigs.
Prof Chua said there had been no other outbreaks since then.
He said that more studies were likely to follow, including finding out in which fruit the virus survived the longest.
Pigs may not be the only conduit of the virus, he said.
Sheep and cows may also pick up the bug and spread it.
He said: 'It can affect a number of animal hosts, like cats and maybe even goats. We don't know.'
http://www.ecologyasia.com/NewsArchives/Mar_2002/straitstimes.asia1.com.sg_singapore_story_0,1870,107860,00.html
Copyright � 2002 Singapore Press Holdings
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World Health Organization
Fact Sheet N� 262
September 2001
NIPAH VIRUS FACTSHEET
Overview: Nipah virus is a newly recognized zoonotic virus. The virus was �discovered� in 1999. It has caused disease in animals and in humans, through contact with infectious animals. The virus is named after the location where it was first detected in Malaysia. Nipah is closely related to another newly recognized zoonotic virus (1994), called Hendra virus, named after the town where it first appeared in Australia. Both Nipah and Hendra are members of the virus family Paramyxoviridae. Although members of this group of viruses have only caused a few focal outbreaks, the biologic property of these viruses to infect a wide range of hosts and to produce a disease causing significant mortality in humans has made this emerging viral infection a public heath concern.
Natural Host: It is currently believed that certain species of fruit bats are the natural hosts of both Nipah and Hendra viruses. They are distributed across an area encompassing northern, eastern and south-eastern areas of Australia, Indonesia, Malaysia, the Philippines and some of the Pacific Islands. The bats appear to be susceptible to infection with these viruses, but do not themselves become ill. It is not known how the virus is transmitted from bats to animals.
Transmission: The mode of transmission from animal to animal, and from animal to human is uncertain, but appears to require close contact with contaminated tissue or body fluids from infected animals. Nipah antibodies have been detected in pigs, other domestic and wild animals. The role of species other than pigs in transmitting infection to other animals has not yet been determined.
It is unlikely that Nipah virus is easily transmitted to man, although previous outbreak reports suggest that Nipah virus is transmitted from animals to humans more readily than Hendra virus. Despite frequent contact between fruit bats and humans there is no serological evidence of human infection among bat carers. Pigs were the apparent source of infection among most human cases in the Malaysian outbreak of Nipah, but other sources, such as infected dogs and cats, cannot be excluded. Human-to-human transmission of Nipah virus has not been reported.
Clinical features: The incubation period is between 4 and 18 days. In many cases the infection is mild or inapparent (sub-clinical). In symptomatic cases, the onset is usually with "influenza-like" symptoms, with high fever and muscle pains (myalgia). The disease may progress to inflammation of the brain (encephalitis) with drowsiness, disorientation, convulsions and coma. Fifty percent of clinically apparent cases die.
Treatment: No drug therapies have yet been proven to be effective in treating Nipah infection. Treatment relies on providing intensive supportive care. There is some evidence that early treatment with the antiviral drug, ribavirin, can reduce both the duration of feverish illness and the severity of disease. However, the efficacy of this treatment in curing disease or improving survival is still uncertain.
Protection of Health Care Professionals: The risk of transmission of Nipah virus from sick animals to humans is thought to be low, and transmission from person-to-person has not yet been documented, even in the context of a large outbreak. Therefore, the risk of transmission of Nipah virus to health care workers is thought to be low. However, transmission without percutaneous exposure (through a break in the skin barrier) is theoretically possible, as respiratory secretions contain the virus. This is why it has been categorized as a biohazardous agent that should be managed in a high-level biosecurity laboratory. It is recommended that close contact with body fluids and infected tissues be avoided if Nipah infection is suspected.
Outbreaks of Nipah and Hendra Viruses:
From September 1998 - April 1999, there was a large outbreak of encephalitis in Malaysia. During the investigation of this outbreak, Nipah virus, a previously unrecognized virus, was identified as the causal agent. A total of 265 people were infected, of whom 105 died. Ninety-three percent of cases had occupational exposure to pigs. An associated outbreak among abattoir workers in Singapore during March 1999 led to 11 cases, with 1 death. These workers had been handling pigs that had been imported from the outbreak areas in Malaysia.
There have been 3 recognized outbreaks of Hendra virus in Australia in 1994, 1995 and1999. Three human cases, leading to 2 deaths were recorded in the 1994 and 1995 outbreaks. In 1995 a horse was infected, with associated human cases. The precise mode of virus transmission to the three Australian patients is not fully understood. All 3 individuals appear to have acquired their infection as a result of close contact with horses which were ill and later died.
For further information, journalists can contact Office of the Spokesperson, WHO, Geneva. Telephone (+41 22) 791 2599; Fax (+41 22) 791 4858; Email: [email protected] All WHO Press Releases, Fact Sheets and Features as well as other information on this subject can be obtained on Internet on the WHO home page http://www.who.int/
http://www.who.int/inf-fs/en/fact262.html
Copyright the WHO
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Nipah in the wilderness
By See Yee Ai
Star Publications (Malaysia) Bhd.
Monday, April 10, 2000
SOMEWHERE in the Tambun hills of Perak an animal may still be harbouring the Nipah virus, only nobody knows for sure what it is. Or if a wildlife reservoir--the wild "source" of the virus--exists.
There are several hypotheses on wildlife reservoirs, none of which are particularly convincing in the absence of hard evidence.
The one most publicly vaunted involves fruit bats, proposed by scientists from the Australian Animal Health Laboratory in Geelong, Australia.
Fruit bats are frequent visitors to the fruit orchards around pig farms in Tambun. While the bats fed on the fruits, they may have contaminated water and food supplies with the their virus-tainted droppings.
In a media release on the Commonwealth Scientific and Industrial Research Organisation (Csiro) homepage, Dr Hume Fields, who worked in Malaysia for six weeks during the outbreak said: "Our experience in Australia with the Hendra virus gave us a head start. Both Hendra virus and Nipah virus are members of the Paramyxoviridae family, and while they are quite distinct, they also have some similarities.
"Knowing the Hendra virus is carried by fruit bats in Australia gave us the clue to take samples from bats when looking into the Nipah virus outbreak in Malaysia," he says.
Dr Fields' studies showed that about 20 bats within four species had Nipah antibodies, while no other wildlife did.
Not everyone is convinced. Veterinary Research Institute (VRI) research director, Dr Abdul Aziz Jamaluddin, describes the bat hypothesis as "convenient."
"They (the Australians) extrapolate that since Hendra's natural hosts are bats, Nipah's should be, too, since they're closely related," he says.
Critics of the bat hypothesis point to the lack of a smoking gun--to date, no one has isolated Nipah from any bat tissue samples.
Presence of Nipah antibodies indicate that bats were infected with the virus, just as pigs, cats and dogs were. A reservoir however, should harbour the virus in their bodies and "secrete" the virus into the environment or other animals.
"If bats are a wildlife reservoir, we should have got at least one tissue sample with the virus," argues Dr Aziz.
Another gaping hole in the hypothesis is Nipah's relatively recent emergence.
While most scientists agree that Nipah may have emerged way before the outbreak in 1998-99, fruit bats have been visiting the fruit orchards for decades. "If it was the bats, the pigs should have been infected a long time ago," says Dr Aziz.
Fruit bats, like this one, are frequent visitors to the fruit orchards around pig farms in Tambun. However, there is no hard evidence to prove that this animal is a carrier of Nipah virus.
On top of that, the bat link is weak even in Hendra's case. "Nobody can give an unequivocal answer how many positive samples they got for Hendra. Some say one, some say three, or five," says Dr Aziz.
(E-mail questions to the Csiro team received no response.)
There is another hypothesis which was much bandied about during the outbreak but has since been discarded--imported polo horses.
"I think that hypothesis came about because people thought Nipah was Hendra-like and Hendra affects horses," says Dr Aziz.
Some veterinarians had speculated that Hendra may have been inadvertently brought over from Australia, escaped to the wild, adapted to pigs as a host and boom, the outbreak.
Examination of the two viruses' genome has largely disproved the idea. While both viruses belong to the same genotype, says Dr Brian Mahy of the Centers for Disease Control and Prevention in Atlanta, United States: "There are far too many differences between Nipah and Hendra for one to be a mutant of the other."
"Horses are just another dead-end host. They don't spread the disease among themselves or to other animals or people. They get the disease and die," says Prof Lam Sai Kit, head of the medical microbiology department at the Medical Faculty, Universiti Malaya.
For Dr Aziz, the hunt for Nipah's wildlife host--if it exists--is still in the early stage.
Basically, the number of animals sampled so far has been small. Bats were the most heavily sampled, with 324 samples. There were too few samples of the other suspects--wild boar, hunting dogs and rodents--to draw any conclusions.
Dr Mahy refuses to forward any hypotheses on Nipah's origins, in the absence of definitive evidence.
However, fruit bats aren't the only suspects and not all hypotheses involve direct contact between pigs and the reservoir animal.
The reservoir animal could have passed the virus to another animal, which in turn infected the pigs.
One of these "secondary hosts" could be the wild boar, which rank high on the list of suspects as well, since they are most closely related to pigs.
"Viruses don't adopt a host overnight. It takes time for a virus to adapt to infecting an animal and causing sickness," says Dr Aziz.
Having the virus adapt first to wild boar before jumping to pigs seems more plausible.
Furthermore, pig farmers involved in the wild boar trade provide a possible route for wild boar to come in contact with pigs--a farmer could have fed the leftover wild boar carcass to his pigs and inadvertently brought the virus in.
But in the absence of proof, it's still open-ended. Dr Aziz says the original host probably would be something that doesn't come into the farms very often; what happened must have been more of a chance occurrence.
Virus hunting has never been an easy game. In the book, Virus hunter: Thirty years of battling hot viruses around the world (Doubleday, 1997), the authors, Mark Olshaker and C.J. Peters say it takes typically between 3,000 and 10,000 animals to verify a wildlife reservoir.
"So far, we've only sampled hundreds; we're still a long way from the mark," says Dr Aziz.
The ecology of paramyxoviruses make it more difficult to narrow down the field.
"We know several paramyxovirus are present among animal populations, including fruit bats. As a matter of fact, we have recently isolated a new paramyxovirus in local fruit bats related to Nipah.
"We are working on a test with the Animal Health Laboratory in Geelong, Australia, to establish whether this new virus can cause disease in man and animals.
However, most of them don't cause disease," says Prof Lam.
In addition the very nature of reservoirs--they keep secreting the virus into the environment without getting sick--makes them difficult to pinpoint.
The only way to know for sure is to spread a wildlife dragnet, sampling methodically animals in the Tambun hills.
The VRI has submitted a proposal to the Science, Technology and Environment Ministry to sample wildlife for Nipah.
"We also need to work with the Wildlife Department because these animals are protected species,"says Dr Aziz.
It will be a long and tedious search. Right now, there isn't even a protocol to sample, test and store the samples.
"Until we have sampled more suspected wildlife species, we can't say for sure whether the virus has a wildlife reservoir," he adds.
That question has to be answered for more than just academic interest. It will tell us if Nipah is something we'll all have to learn to live with or if it was a fluke chance of nature and with the last of the livestock cases, we can all breathe easier--for now.
http://agrolink.moa.my/jph/dvs/nipah/star000410/nipah-wild.html
Copyright Star Publications (Malaysia) Bhd.
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CONTENT COPYRIGHT THE WALL STREET JOURNAL, NATIONAL GEOGRAPHIC, THE WHO, THE STAR, THE STRAITS TIMES. THIS CONTENT IS INTENDED SOLELY FOR EDUCATIONAL PURPOSES.
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