Recent Common Ancestry of Ebola Zaire Virus Found in a Bat Reservoir [Journal Article]
PLoS Pathogens - pathogens.plosjournals.org
27 Oct 2007
Roman Biek et al.
Identifying a natural reservoir for Ebola virus has eluded researchers for decades [1,2]. Recently, Leroy et al. presented the most compelling evidence to date that three species of fruit bats (Hypsignathus monstrosus, Epomops franqueti, and Myonycteris torquata) may constitute a long-missing wildlife reservoir for Ebola virus Zaire (EBOVZ) [3]. These bats, caught near affected villages at the Gabon–Congo border, appear to have been asymptomatically infected and, in seven cases, yielded virus sequences that closely matched those found in the human outbreaks happening about the same time.
Leroy et al.'s phylogenetic analysis of the partial sequences of the viral polymerase (L) gene derived from humans and bats emphasized the interspecific relationships to related filoviruses. Here, we show that (1) despite their short length (265 bp), these sequences also provide critical information about the intraspecific history of EBOVZ, and (2) based on the genetic data available so far, the association of the virus with fruit bats in the sampled area can only be traced back a few years.
Consistent with previous analysis using glycoprotein (GP) gene sequences [4], results for the L gene show that viruses amplified from more recently collected samples appear to be direct descendents of viruses seen during previous outbreaks. This relationship is not only apparent for viruses found in 1976–1995 compared with those found in 2001–2003, but also within the latter group (Figure 1). In essence, this means that all genetic variation seen thus far in EBOVZ, including virus amplified from fruit bats, appears to be the product of mutations that have accumulated within the last 30 years.
Sparrows in China Carry Bird Flu Virus: Scientist
Xinhua (Posted by english.people.com.cn)
27 Oct 2006
Chinese scientists recently reported that they found H5N1 bird flu virus in sparrows two years ago, the first time the virus has been detected in the common, non-migratory bird on the Chinese mainland. Wuhan Institute of Virology in central China's Hubei Province tested excrement samples from 38 sparrows after an outbreak of bird flu in a county in Henan Province in 2004. Some of samples tested positive of H5N1 virus, said Li Tianxian, a researcher with the institute.
"There's no need for the public to panic. The findings are two years old and there is no indication that sparrows pose a risk," Li told Xinhua, adding that scientists found the bird flu virus in sparrows in the region of Hong Kong in 2002 and also in Turkey and South Africa. Working with the Beijing Institute of Zoology, under the Chinese Academy of Sciences, the scientists isolated four H5N1 strains among the 25 positive excrement samples.
Li said tests on the four strains have shown they are a new genotype of H5N1, adding that researchers did not find dead sparrows. It was thought that bird flu was mainly transmitted by migratory water fowl, but this finding proves that non-migratory birds are also a potential channel for bird flu transmission, she told the Chutian Metropolitan News published in Hubei Province. The finding was published in December of last year in the U.S-based Journal of Virology, according to the newspaper.
Isolation from Cattle of a Prion Strain Distinct from That Causing Bovine Spongiform Encephalopathy [Journal Article]
PLoS Pathogens - pathogens.plosjournals.org
20 Oct 2006
Vincent Béringue et al.
To date, bovine spongiform encephalopathy (BSE) and its human counterpart, variant Creutzfeldt-Jakob disease, have been associated with a single prion strain. This strain is characterised by a unique and remarkably stable biochemical profile of abnormal protease-resistant prion protein (PrPres) isolated from brains of affected animals or humans. However, alternate PrPres signatures in cattle have recently been discovered through large-scale screening.
To test whether these also represent separate prion strains, we inoculated French cattle isolates characterised by a PrPres of higher apparent molecular mass—called H-type—into transgenic mice expressing bovine or ovine PrP. All mice developed neurological symptoms and succumbed to these isolates, showing that these represent a novel strain of infectious prions. Importantly, this agent exhibited strain-specific features clearly distinct from that of BSE agent inoculated to the same mice, which were retained on further passage.
Moreover, it also differed from all sheep scrapie isolates passaged so far in ovine PrP-expressing mice. Our findings therefore raise the possibility that either various prion strains may exist in cattle, or that the BSE agent has undergone divergent evolution in some animals.
State Investigating Dead Birds
Press & Sun Bulletin - pressconnects.com
29 Oct 2006
Dave Henderson
The Department of Environmental Conservation is investigating the mysterious deaths of dozens of water birds found along the shores of eastern Lake Ontario since last weekend. Tests for Type E Botulism and other clinical analyses are being conducted on the carcasses of gulls, grebes, and loons collected from Sodus Bay to Deer Creek Marsh by the department's Wildlife Pathology Unit. Type E Botulism was first documented in birds near Lake Ontario in 2002, but the mortality this year is the largest so far.
In July 2002 and August 2005, several gulls were tested from the eastern basin of Lake Ontario and many of those tested positive. There have been no reports of any human illnesses associated with the outbreaks. Type E Botulism is a specific strain of botulism most commonly affecting fish-eating birds. The associated neurotoxin produced by actively growing bacterium (Clostridium botulinum) causes paralysis in the affected birds and often results in drowning.
The ingestion of the toxin produced by the botulism bacterium and can be harmful to humans who eat contaminated birds or fish. Cooking may not destroy the botulism toxin. To date, Type E Botulism has not been found in any fish from Lake Ontario or the St. Lawrence River. Hunters and anglers are advised not to take waterfowl or fish that appear sick or are acting abnormally. Waterbirds impacted by botulism toxin cannot fly and their legs become paralyzed.
Rare Chimpanzees Face Extinction
Guardian (Posted by ippmedia.com)
14 Sep 2006
Adam Ihucha, Arusha
A renowned American wildlife conservationist has expressed fears that the rare chimpanzee species found in western Tanzania could become extinct as a result of a mysterious disease that are decimating the primate genus in large numbers. The scientist, Dr Magdalena Lukasik-Braum, known for her research on wildlife in the country said, the rare species at Mahale Mountain National Park in Kigoma Region would become extinct if the disease is not checked. Dr Lukasik-Braum told The Guardian: ’The deadly disease that recently claimed scores of the rare monkey’s species in Mahale Mountain National Park is still ravaging them after five more died.’
’The situation is critical because the animals are threatened with extinction. Its current population is less than fifty,’ Dr Lukasik-Braum said, after concluding a research on the chimpanzees. African primates have been the object of international attention all over the world, she said, adding that her recent study findings show the population of the species is on the decline in their natural habitats. ’Some of the threats to these ape populations are similar to those affecting other wildlife in the region (East and Central Africa): political instability in the countries where they are found, habitat destruction and bush-meat trade,’ Dr Lukasik-Braum noted.
But there is an additional factor that affects apes, especially chimpanzees more than any other animal - human diseases. She said the chimpanzees are genetically so close to people that they are susceptible to almost all germs which affect humans. Dr Lukasik-Braum said since Tanzania is recognised worldwide for its political stability and safety and where the chimps meat trade is non-existent, human diseases, especially respiratory ones, are by far the biggest threat to habituated chimpanzees.
Portsmouth Company Develops Way to Track Spread of Disease
UnionLeader.com
29 Oct 2006
Michael Cousineau
Tracking the avian "bird" flu will be easier thanks to technology developed by a Portsmouth company, Global Relief Technologies. People tracking the flu will use PDAs, or hand-held computer devices, to plug in information about patients and conditions. That information, which will note the person's exact location through GPS tracking, will be sent by way of satellite to the company headquarters and quickly analyzed with proprietary mission-specific software.
The U.S. Department of Defense believed in it so much that it awarded the company a $3.5 million contract to provide about 120 PDAs early next year to Marine Corps field crews working in Southeast Asia. Plans call for the information to be shared with the World Health Organization. "The overall objective of the contract is to identify what's going on with much greater speed and effect and accuracy with the avian flu in Southeast Asia and the Pacific Rim countries and see if it had made a jump - and whether it mutated into something more aggressive," CEO Michael Gray said in an interview yesterday.
The technology already is being employed by Marines in Afghanistan for major reconstruction projects and by Raytheon in Iraq to protect American troops. It also was used by Marines after Hurricane Katrina struck the Gulf Coast last year. For this contract, five-man teams comprised of expeditionary Marine forces will collect information on the flu, such as the number of birds found dead and where the flu had spread in humans.
U.S. Expecting More Low-Pathogenic Bird Flu
Union-Tribune - signonsandiego.com
26 Oct 2006
The U.S. government said Thursday additional tests of ducks in Ohio showed the birds did not have a low-pathogenic strain of the H5N1 virus, but warned new cases of bird flu would be found in the coming months in the United States as more tests are conducted. Preliminary tests had detected a strain of the H5N1 virus in “apparently healthy” wild birds sampled Oct. 8 in Ottawa County, located on Lake Erie about 15 miles southeast of Toledo. Additional tests showed that no virus was present.
The U.S. government said Thursday additional tests of ducks in Ohio showed the birds did not have a low-pathogenic strain of the H5N1 virus, but warned new cases of bird flu would be found in the coming months in the United States as more tests are conducted. Preliminary tests had detected a strain of the H5N1 virus in “apparently healthy” wild birds sampled Oct. 8 in Ottawa County, located on Lake Erie about 15 miles southeast of Toledo. Additional tests showed that no virus was present.
The departments are working with states to collect between 75,000 and 100,000 wild bird samples in addition to more than 50,000 environmental tests throughout the United States. A low-pathogenic strain of the flu, which produces less disease and mortality in birds than does a high-pathogenic version, poses no threat to humans. The government said in the future it will post possible low-pathogenic H5N1 detection on the Internet at wildlifedisease.nbii.gov/ai/LPAITable.pdf or www.usda.gov/birdflu.
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