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Contagious equine flu in dogs

A Cornell University virologist has isolated a highly contagious equine flu virus that is spreading a sometimes-fatal respiratory flu among dogs, and is responsible for a major dog-flu outbreak in New York state. There is no evidence that the virus could infect people. According to a paper published in the online version of Science magazine, this is the first time an equine flu virus has been found to jump species. The equine influenza virus, H3N8, was isolated at Cornell’s College of Veterinary Medicine after University of Florida researchers sent fluid and tissue samples from greyhound race dogs that had died from a respiratory illness at a Florida racetrack in January 2004. “Of all animals, dogs have the most intimate contact with humans on a daily basis, so the potential for human infection has to be in the back of our minds,” said Ed Dubovi, director of the virology center at Cornell’s Animal Health Diagnostic Laboratory, who isolated the virus from the University of Florida samples. Still, he added, there is no evidence of the virus jumping to humans, and there is no expectation of it doing so. It is possible the equine virus has been infecting dogs for some time, although the symptoms are very similar and could be mistaken for common “kennel cough,” a bacterial disease related to pertussis (whooping cough) in children. Nevertheless, the paper cautions that the newly discovered flu virus must be closely monitored.

With close to 100 percent of dogs exposed to the virus becoming infected and about 80 percent of infected dogs showing symptoms, the flu could be spreading throughout the country. It was originally documented in greyhounds at tracks and kennels but now is infecting all breeds of dogs. Ongoing testing is being done to track the spread of the virus to different regions of the country. “Right now, we have a major outbreak of this disease in all breeds of dogs in New York state,” said Dubovi, noting that symptoms can include high fever and a respiratory infection that lasts a few weeks, although 1 to 5 percent die from related hemorrhagic pneumonia. From January to May 2005, outbreaks occurred at 20 racetracks in 10 states (Florida, Texas, Arkansas, Arizona, West Virginia, Kansas, Iowa, Colorado, Rhode Island and Massachusetts), according to the paper.

“This infection will become a major concern for all dog owners, since 100 percent of dogs are susceptible to infection by this virus,” said Dubovi. “With 50 million pet dogs in this country, even if you have 1 percent mortality, this is going to result in a number of dogs dying from it.” The Centers for Disease Control and Prevention (CDC) in Atlanta sequenced the virus’ entire genome and found all the segments were from the equine virus. This is unusual, because flu viruses will often swap genetic material with other flu viruses when they jump species. For a new virus to enter another species it must overcome a number of barriers, such as finding a cell receptor to bind to in order to enter the cell and to reproduce sufficiently in the new host. “There are probably many examples of viruses jumping species, but then it becomes a dead-end issue,” said Dubovi. Researchers have long known that equine flu was capable of growing in dogs, since scientists experimenting with equine influenza use cell lines from canine kidney cells.

When Dubovi first received the University of Florida samples, he and his colleagues isolated a virus and determined that it was an influenza not typically found in dogs. The next step was to test to see if it was an avian flu virus, like the virulent H5N1 that has jumped from birds to humans over the last few years. A highly sensitive test — called a PCR (polymerase chain reaction) that amplifies and detects small amounts of DNA or RNA in a blood or tissue sample — ruled out avian flu strains H5 and H7. The isolate was then sent to the CDC where Ruben Donis found that it tested positive for equine influenza virus. Donis also ruled out the possibility that the sample had been contaminated with equine virus from another source.

Science Daily
October 25, 2005

Original web page at Science Daily

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Visceral leishmaniasis: successful vaccine trial in dogs

Visceral leishmaniasis, which is the most severe form of that group of diseases, affects 500 000 people in the world each year. It is caused by a protozoan, Leishmania infantum, transmitted by sand fly bites. There is no vaccine for this disease, which can rapidly lead to death if no treatment is given. In the most heavily affected areas, the dog population is hit heavily by infection. It acts as parasite reservoir for humans. Development of a vaccine for dogs could help brake transmission of the disease to humans, by reducing this reservoir. Such prevention treatment has just been tested successfully on dogs by an IRD team in Montpellier, in conjunction with the Rocher veterinary clinic (La Garde, Var) and the biopharmaceutical company Bio Véto Test (La Seyne-Sur-Mer, Var). The first results showed total lasting protection of these animals against the disease, could open the way towards the development of a human vaccine.

Visceral leishmaniasis, which is the most severe form of the leishmaniases, hits an annual total of 500 000 people, mostly in the developing countries. It is caused by the parasite Leishmania infantum. A flagellate protozoan, it uses as vector an insect resembling a midge, the sand fly, colonizing the intestine and then the salivary glands. The female insect feeds on mammals’ blood. It can thus pass the parasite on to humans by a single bite. Once in the blood stream, L. infantum passes into particular cells of the immune system, the macrophages. These eventually burst, releasing the parasites which move on to penetrate other cells. The infected subject suffers bouts of fever, anaemia, enlarged spleen and liver, and weight loss. In the absence of treatment, these clinical signs usually announce a fatal outcome.

The sand fly sucks blood from mammals other than humans. This is how, right around the Mediterranean rim, 5 million dogs, a proportion of from 1 to 42 % depending on the area, are affected by visceral leishmaniasis. These animals are thus a reservoir for these parasites, which continuously feed the mammal-sand fly-human cycle. In this context, development of a canine vaccine would help reduce the portion of the animal population infected. The risks of transmission of the disease to humans would in this way be indirectly reduced.

Up to now, several dog vaccines, mostly developed from whole dried parasites, have proved not to be really effective. A team from the IRD Montpellier research centre, working with the Rocher veterinary clinic (La Garde, Var, France) and the biopharmaceutical firm Bio Véto Test (La Seyne-Sur-Mer, Var), have recently produced and tested a new type of treatment, composed solely of antigen proteins excreted by the parasite. The first trials indicate that this would completely and lastingly protect dogs against the disease.

Twelve out of 18 dogs included in the study were treated with increasing doses of protein antigens excreted by the parasite (that is 50, 100, 200 micrograms) made up to a formula with an adjuvant. The other six received no treatment. Two injections at an interval of three weeks resulted in infection of all the animals with L. infantum. They were followed up for two years in order to monitor the progress of the disease. The mixture of parasite proteins proved to be especially effective, as 100% protection was obtained for the doses of 100 micrograms (six immunized dogs out of six) and 200 micrograms (three out of three).

The researchers also focused on the changes to the immune system brought on by the vaccination. Laboratory experiments showed that the effectiveness of the vaccine stems from the activation of certain cells of the immune system, the T lymphocytes of type Th1. These induce the infected macrophages to produce nitric oxide, highly toxic for cells. This process, which did not occur in the untreated dogs, thus enables macrophages to get rid of the parasites that are infecting them. The animal thus acquires long-term protection against visceral leishmaniasis.

Although this vaccine’s effectiveness has been shown only on a limited number of animals, it is a further step towards protection of dogs against this disease. These results, confirmed indeed by the first, highly encouraging, data from a large-scale clinical trial currently under way (phase III), are promising for efforts to reduce transmission of leishmaniasis to humans. They also point to new lines of investigation for elaborating a possible human vaccine. An integrated research project, involving several IRD groups, has just been set up in India, to work on this. It should lead to an assessment of the effectiveness of such a vaccine in humans.

Science Daily
September 13, 2005

Original web page at Science Daily

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China: 1st human rabies death in Beijing in 11 years

A male resident in Beijing died of hydrophobia [rabies] the 2nd week August 2005, the 1st death caused by hydrophobia in this capital city since 1994, the Municipal Health Bureau announced on Fri 12 Aug 2005. The man, 45 years of age, was a native of neighboring Hebei Province. He had been living in Beijing before his death. He died of the fatal disease at the Ditan Hospital after being bitten by a pet dog, according to the Bureau.The Bureau urged local citizens to keep a close eye on their pet dogs and have them regularly vaccinated against rabies.

Dogs account for 99 percent of human cases worldwide, and for 95 percent of post-exposure vaccinations. From 1984 to 1989, the annual reported numbers of cases of rabies in China were between 4000 and 6000, but decreased after 1990. In 1996, the reported cases decreased to the lowest level, from 3520 in 1990 to 159. However, the number of reported cases has been continuously increasing since 1998, reaching 1122 in 2002, a 7.06-fold increase as compared to the number in 1996. The epidemic areas were mainly located in the southeastern and southwestern parts of the country, such as Sichuan, Hunan, Guangxi, Guangdong, Anhui, Fujian, etc. The rabies-free status of Beijing in recent years can probably be attributed to the compulsory vaccination of pet dogs, which seems to be rigidly enforced in urban areas In contrast, there is no requirement for dogs raised and sold for meat to be vaccinated. The majority of dogs which have been killed as a result of rabies outbreaks have been in dog meat production areas, where there are few if any pet dogs.

ProMed Mail
August 30, 2005

Original web page at ProMed Mail

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Gene therapy to treat haemophilia; cure achieved in dogs

Progress in gene therapy to treat haemophilia has been impressive in the past few years. Gene therapy has been used to successfully treat haemophilia in dogs. A leading researcher from Philadelphia USA, Professor Katherine High, is examining the obstacles to successful gene therapy in human patients with haemophilia. She hopes that the problems may be overcome in the next five years to develop a successful gene transfer approach for sufferers of haemophilia.

“It has taken approximately 5 to 8 years to move from a cure for haemophilia in mice to a cure in dogs. This has been achieved by multiple gene transfer strategies. Clinical studies have identified which aspects of gene transfer therapy in dogs are directly applicable in humans and have identified potential problems, such as mode of delivery, which must be overcome before applying this approach in humans,” said High. Professor High will review these exciting findings and the steps to achieving a successful outcome in humans at the XXth Congress of the International Society on Thrombosis & Haemostasis in Sydney.

Science Daily
August 30, 2005

Original web page at Science Daily

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First dog cloned

Move over, Fluffy; cloning isn’t just for cats anymore. The South Korean researchers who announced earlier this year that they had successfully derived stem cells from a cloned human embryo have now created the first-ever dog clone, a male Afghan hound, they report in Nature this week. The puppy–named Snuppy for the researchers’ Seoul National University–was born by cesarean section on April 24 to a yellow Labrador surrogate mother and turned 100 days old yesterday (August 2). A second cloned dog lived just 22 days before succumbing to aspiration pneumonia. A postmortem analysis showed no signs of “any congenital defect due to cloning,” said Woo Suk Hwang, the leader of the Korean team. A third pregnancy resulted in a miscarriage.

Until now, somatic cell cloning in dogs has been hampered by limited success in maturing canine oocytes in vitro, said Hwang. Such maturation is necessary because unlike those of other domestic animals, canine oocytes aren’t mature at ovulation. They’re ovulated at prophase of the first meiotic division and undergo maturation in the distal part of the oviduct for at least 48 to 72 hours. The dog’s opaque ova also make manipulation difficult.

Hwang attributed his team’s success to their ability to produce a nuclear transfer construct using in vivo matured oocytes, to transfer it into a surrogate mother at an early stage of development without in vitro embryo culture, and to optimize the conditions for transfer “through trial and error.” “We were able to determine the exact ovulation and embryo transfer time,” Hwang told The Scientist via E-mail. “Through hormonal and cellular analysis of vaginal smears, we made a database for prediction of ovulation time and for estrus synchronization. Thus, our team could obtain a good number of in vivo matured oocytes with good quality and find good surrogate mothers with an appropriate estrous cycle.” Altogether, the researchers collected an average of 12 oocytes from 123 donor females to create nearly 1,500 successfully reconstructed embryos. Of those, 1,095 were transferred back into the same 123 surrogates. The researchers used “naturally collected eggs” rather than the hormone stimulation typical of in vitro fertilization, coauthor Gerald Schatten, of the University of Pittsburgh, noted.

The team chose an Afghan hound because the dog was known to have a “gentle and docile pedigree,” Hwang said. They also had access to a good collection of photos of the dog, which had unique fur color and appearance, when it was a puppy, he said, making it easier to distinguish whether the clone was identical. Microsatellite analysis of genomic DNA from the donor, the cloned dogs, and the surrogates confirmed that the clones were genetically identical to the donor.

Other animal cloning researchers hailed the report, but noted the low efficiency of transfer–2 live births out of 123 transfers, or 1.6%–and the greater availability of canine surrogates and ova in South Korea than in the United States. “The efficiency is still pretty dismal,” said Jorge Piedrahita, who studies animal cloning at North Carolina State University. Cattle embryonic transfer efficiency is about 10%, while pig efficiency is as high as 8% to 9%. “The statistic they cite is somewhat misleading,” Piedrahita told The Scientist. “It is not 1.6%; it should be 1 out of 1,095. It’s an important advance, but I doubt the utility at that efficiency.”

Phil Damiani, chief scientific officer of Genetic Savings & Clone, which announced in December 2004 that it made the world’s first sale of a cloned cat, said the efficiency was “probably one of the lower ones ever done for cloned animals.” The company had hoped to be the first to produce a cloned dog and a few years ago had a clone that nearly came to term, Damiani told The Scientist. The fetus was alive on ultrasound, but stopped breathing by the time it was delivered by cesarean section. The Korean team has “jumped ahead,” he said.

Damiani said that his company remained convinced that their technology–which relies on chromatin transfer, rather than nuclear transfer, and egg and embryo assessment prior to cloning and transfer–would eventually make it possible to clone dogs commercially. The company expects to be able to produce a cloned dog in the next few months, said Genetic Savings & Clone spokesperson Ben Carlson. “People have been asking us, does this mean that tomorrow you’ll be able to start offering this service commercially? We wouldn’t be able to make a successful business out of using the technique the South Koreans used,” Carlson said. The low efficiency rate, combined with stricter animal welfare rules in the United States that limit the number of times eggs can be harvested and that transfers can be made, would make it impossible. But “it certainly validates our contention that dogs can be cloned,” he said. “It doesn’t mean we’re quite there yet.”

Schatten, who traveled to Seoul this past weekend, was quick to note that the team does not support the cloning of pets “or any other members of our family. Nuclear transfer should be restricted to medical research,” he told The Scientist via E-mail. “This is not to make dogs by this unnatural method, but to advance stem cell science and medicine.”

The Scientist
August 16, 2005

Original web page at The Scientist

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Puppy love conquers community violence

A group of leading veterinarians says there’s clear evidence emerging that teaching people to look after their dogs and other companion animals can help reduce the incidence of violent crime and violence in communities.
Australian Veterinary Association (AVA) NSW President, Dr Mark Lawrie says more public funds are needed to continue the research and carry out education programs particularly through the Animal Management in Rural and Remote Indigenous Communities (AMRRIC) organisation. “Just as it has been conclusively shown that young people who are cruel to animals tend to grow up to be violent adults, the reverse can also be true. Young people who are taught to be kind to animals tend to be less violent adults. “In fact, recent international research found a group of 4th graders who were taught how to be kind to animals also had increased empathy towards humans.”

Dr Lawrie, who is also Secretary of AMRRIC, said AMRRIC was playing a role in helping geographically remote aboriginal communities better look after the health of their dogs by providing veterinarians who travel to communities to treat and operate on sick and suffering animals. “Until recently there has been a crisis in the health of dogs in many indigenous communities brought about by overpopulation and lack of resources to properly look after the animals. But we are now seeing reductions in dog populations in some communities that have asked for assistance from in one case, 400 dogs down to 75. “AMRRIC’s work is based on the belief that if you are able to look after the health of your dog or companion animal, you are more likely to look after your own health.

“From the work that has been done so far, it’s clear that education programs need to be developed and implemented with the assistance of these communities that will promote kindness to animals and people. “Family violence is a problem in all communities in Australia and around the world. But it’s also acknowledged now by indigenous leaders that many children are growing up in communities where violence has become a normal and ordinary part of life. “We believe that one way to combat this problem in remote indigenous communities is to promote animal health and welfare through education and link that to human health and welfare. We are calling for more such programs to be developed and implemented across society but in key areas with less access to services such as indigenous communities,” Dr Lawrie said.

E-mail address Bloglet
June 21, 2005

Original web page at WVA

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Zoo reverses vasectomy on bush dog

Three yapping, cuddly South American bush dog pups at the Saint Louis Zoo are making fertility history among wild canids, with implications for the rest of the animal world. Youngsters Mariana, Turi and Sherman, resembling chubby, furry, Chihuahuas, were born in January following a successful, first-of-its-kind vasectomy reversal on the pups’ father. The procedure was performed in August 2003 by St. Louis infertility specialist, Dr. Sherman Silber, a 15-year zoo consultant, who perfected it on more than 4,000 humans before trying it on Brent, the bush dog.

The reversible vasectomy holds the best hope for the world’s zoos to manage animals genetically and behaviorally, said Ingrid Porton, the Saint Louis Zoo’s primate curator. She also is codirector of the American Zoo and Aquarium Association’s Wildlife Contraception Center in St. Louis. “It allows us to manage reproduction in a responsible way, and meet (animals’) behavioral and social needs,” Porton said. “It’s so much more preferable not to isolate animals to prevent breeding; with a reversible contraception, we can allow them to live in a social group.”

The idea for a reversible, non-chemical form of contraception for males came out of a St. Louis study of female bush dogs’ reproductive habits, and required having four males — Brent among them — not producing sperm.
Silber, assisted by zoo veterinarians, performed the reversible vasectomies in January 2002. The researchers wanted the mating behavior but not for the females to get pregnant because once they stop being in heat, they’ll refuse males, said Dr. Randall Junge, the zoo’s director of animal health. “Vasectomies allowed (the males) to maintain reproductive behavior but stop the fertility,” he said.

Chemical contraception that shuts down testosterone production is not ideal because it alters behavior, Porton said. At the end of that study, Silber and zoo vets reversed the vasectomies, and the effectiveness of the reversal was tested on Brent. The proof is his three yelping pups, which likely will go on public display next week at the Saint Louis Zoo. Porton said she is unaware of vasectomy reversals of other zoo species in the world. Dr. Cheri Asa, the Saint Louis Zoo’s director of research, has said contraception allows for controlled pairings, or “high-tech matchmaking,” that maintains the animals’ genetic diversity, prevents inbreeding, and permits individuals to live in natural social and family groups. Silber, who performed his first vasectomy reversal on a human male in 1981, said he modified the procedure slightly for the bush dog, and would for other exotics as well. He called both the vasectomy and its reversal simple procedures that can be taught easily to veterinarians. He performed a reversible vasectomy on a chimpanzee a month ago at the Tulsa Zoo.

Male bush dogs are not only sharing the responsibility of contraception, they wholeheartedly share in parenting, too, zoo experts said. “There is no more involved wild canid parent than the bush dog,” Porton said. They clean the female and pups after birth, and even have been observed acting as midwife, by pulling a pup from the birth canal, she said. After the pups were vaccinated and weighed, they returned to their waiting parents in the Saint Louis Zoo’s makeshift den, where the pups pawed at their dad’s mouth to indicate they were hungry. He chews their food before giving it to them. Bush dogs are about the size of a terrier, with short legs and a short tail, and webbed feet that enable them to chase prey in the water. They live in packs, eat large rodents, and dig burrows. Brent was born at the Little Rock Zoo in 2000 and arrived in St. Louis in 2002, when he was paired with Foosa. She was born on St. Maarten in the Caribbean in 1999.

Yahoo
May 24, 2005

Original web page at Yahoo

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Ebola virus: from wildlife to dogs

Since 1976 the Ebola virus has caused some lethal human epidemics in Central Africa. Research now indicates that humans do not become directly contaminated from the animal reservoir, which is in any case still unknown, but from infected carcasses of chimpanzees, gorillas and certain forest antelopes. Results have come from work conducted over the past several years by IRD scientists and their partners to shed light on the virus’s propagation paths. The discovery of Ebola virus antibodies in several species of non-human primate suggests the existence within this fauna of different degrees of susceptibility to Ebola and, possibly, of strains of various levels of virulence.
However, most large primates, once infected, soon die of the disease. Their bodies then become a potential source of contamination for humans, but also for certain domestic animals.

Ebola virus antibodies were detected in dogs exposed to the virus during the latest epidemics, which suggests that these animals may well have been infected and can therefore be a new source of transmission to humans. Ebola virus infection in humans provokes a violent hemorrhagic fever. It usually flares up as intense epidemics. These kill 80 % of the people infected. Seven such outbreaks have hit Gabon and the Republic of Congo since 1994, leading to 445 cases resulting in 361 deaths. Ebola virus thus constitutes a grave public health problem in these countries. No medicine or vaccine is currently available, only prevention and rapid control of epidemics by isolation of disease victims can limit its spreading.

Bio.com
April 26, 2005

Original web page at Bio.com

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To walk again

A pioneering treatment has allowed paralysed dogs to regain some movement. The results have raised hopes that the method will work in people too. So far, nine dogs paralysed in road accidents or by spinal disc injuries have been treated by veterinary surgeons Robin Franklin and Nick Jeffery of the University of Cambridge. Within a month, all regained the ability to make jerky movements in their hind legs, Jeffery told a meeting in Birmingham, UK, this week, although they are only slowly gaining the ability to support their own weight.

Many different approaches to treating spinal injuries are being explored, but promising results in small animals such as rats have often not been repeated in larger animals. That is one of the reasons why the dog results are exciting, says Geoffrey Raisman of the Institute of Neurology at University College London, one of the pioneers of the method used by the Cambridge team. “I think that these findings in dogs are directly relevant to the human situation,” he says. “Of course, we can’t know for sure without doing the work but it is a very good indicator that we can expect the same effects. We are hoping to start similar trials in humans within a couple of years.”

In Australia, three patients have already been treated using the same method (New Scientist, 12 July 2002, p 18). But the results will not be revealed until 2007. Jeffery agrees the results seen in the nine dogs are encouraging, but says a full recovery may require a combination of methods. “It is exceedingly improbable that one simple intervention alone will permit full recovery of locomotor activity after this type of extremely severe spinal cord injury,” he cautions.

His team is one of several studying the use of specialised cells called olfactory ensheathing glia cells, OEG cells, found in the back of the nose, are support cells for the only nerve cells in the central nervous system capable of constant regeneration. For the Cambridge study, OEG cells were collected by opening the skulls of the dogs. The cells were multiplied in the lab and then injected into the damaged part of the spinal cord.

As well as regaining some movement, the dogs also seemed to recover some sensation below the injury site. Three of the dogs can warn their owners when they have a full bladder, Jeffery says, though they have not regained control. There are no signs that the dogs have regained a proper pain response, but neither do they appear to suffer pain from the severed nerve, a potential side effect of the treatment. Franklin is looking for an alternative source of OEG cells, as three of the nine dogs have suffered seizures as a result of the surgery. The team has found a form of stem cell in the nasal mucosa that can be turned into OEGs in the lab. These cells can be collected by inserting a simple swab into the nose. The Australian team is using a similar approach.

A trial of another spinal injury treatment in dogs hit the headlines in December. Injections of a chemical called PEG appeared to greatly boost recovery (New Scientist, 11 December 2004, p 9). However, PEG has to be injected within 48 hours of an injury. By contrast, all nine dogs treated at Cambridge had been paralysed for at least three months without showing any sign of recovery.

New Scientist
April 26, 2005

Original web page at New Scientist

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Statements BSAVA and WVA following information on MRSA in dogs and cats (ref. Veterinary Sciences Tomorrow, News March 29, 2005)

Current BSAVA statement on MRSA.
Current scientific evidence supports the opinion that the risk of pet-transmitted MRSA is small and that pet owners that undertake hygienic precautions are at minimal risk. MRSA, furthermore, does not normally harm healthy people including pregnant women, babies and children. The BSAVA, however, recommends that all reported infections with MRSA are investigated and that medical and veterinary staff co-ordinate in eliminating infection. The BSAVA strongly advocates the responsible use of anti-bacterial agents to minimise the development of resistant species and strains of all bacterial pathogens particularly those with zoonotic potential. High-risk individuals (long-term sick, elderly or patients with a poor immune system for example) may need to take extra care and seek advice from their veterinary surgeon and doctor.

Source: BSAVA Policy on MRSA, Created on 31 March 2005

BSAVA
April 12, 2005

Original web page at BSAVA

Statement WVA: Plea to pet owners MRSA panic unnecessary Commenting on fears being generated over MRSA (Methicillin Resistant Staphylococcus Aureus) in pets, the President-Elect of the BVA (British Veterinary Association) Dr Freda Scott-Park begged pet owners not to panic. The alarm being generated is completely unnecessary, she said. While MRSA has been isolated from a variety of domestic animals it is important for people to realise that the incidence is still very, very low. Dr Scott-Park stressed that any loss of a much-loved pet, whatever the cause, is tragic, but the circumstances surrounding the death of the dog that has triggered the latest concerns were, to say the least, extremely unusual as well as deeply regrettable. Clearly awareness of the potential dangers of MRSA is vital but detailed information was provided to the veterinary profession at the beginning of the year (via the Journal of Small Animal Practice, the journal of the British Small Animal Veterinary Association (BSAVA)). Practical advice and guidelines to the profession will also continue to be issued as and when relevant information becomes available. Dr Scott-Park continued: Current scientific evidence supports the opinion that the risk of pet-transmitted MRSA is small and that pet owners who undertake hygienic precautions are at minimal risk. MRSA does not normally harm healthy people including pregnant women, babies and children. Furthermore, there are no proven recorded cases of MRSA jumping from animal to human. High-risk individuals (long-term sick, elderly or patients with a poor immune system for example) may need to take extra care while vets need to remain aware of the need for extra precautions when treating similarly potentially vulnerable animals. In emphasising that there was already widespread awareness within the veterinary profession of MRSA and the problems that could occur Dr Scott-Park noted that the BVAs major concern at present relates to MRSA passing from humans to animals, the more likely path,” which was why she said we are urging vets to adopt best practice and take precautions – use sterile gloves, masks and scrub suits during operations – to prevent animals getting the organism.

E-mail address: Boglet.com
April 12, 2005

Original web page at WVA

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Reemergence of canine Echinococcus granulosus infection

As a consequence of large-scale outdoor slaughter of sheep during the 2001 foot and mouth disease (FMD) outbreak in the United Kingdom and the possibility of increased risk for transmission of Echinococcus granulosus between sheep and dogs, a large survey of canine echinococcosis was undertaken in mid-Wales in 2002. An Echinococcus coproantigen-positive rate of 8.1% (94/1,164) was recorded on 22% of farms surveyed, which compares to a rate of 3.4% obtained in the same region in 1993. Positivity rates between FMD-affected properties and unaffected ones did not differ significantly. Significant risk factors for positive results in farm dogs were allowing dogs to roam free and the infrequent dosing (>4-month intervals) of dogs with praziquantel. When these data are compared to those of a previous pilot hydatid control program in the area (1983–1989), an increase in transmission to humans appears probable.

Echinococcus granulosus infection in sheep and dogs has been known to be endemic in parts of Wales and the English borders for many decades. An analysis of national hospital records for the period 1974–1983 showed that the incidence of human cystic echinococcosis was 0.2 cases per million in England and 2 cases per million population in Wales, with highest rates (5.6 cases per million) occurring in southern Powys County. To reduce the incidence of human cystic echinococcosis (also called cystic hydatid disease), a voluntary hydatid control program of supervised dog dosings at weekly intervals with praziquantel was introduced in south Powys in 1983 and continued until 1989. Ovine hydatidosis rates in the intervention area dropped from 23.5% to 10.5% after that period, and experimental use of sentinel lambs confirmed that transmission of E. granulosus was significantly reduced by this regime. Trend analyses of hospital admissions of human hydatid disease showed that, by 1993, clinical cystic echinococcosis disease in children (<15 years old) had ceased in the intervention area.
However, a new focus of human cystic echinococcosis was identified for the period 1984–1990 in an area bordering south Powys, namely, the northern parts of the counties of Gwent and mid-Glamorgan. Furthermore, canine echinococcosis rates, measured indirectly with an Echinococcus-specific coproantigen enzyme-linked immunosorbent assay (ELISA), reflected the clinical data for intervention and nonintervention areas.

In 1989, the supervised dog-dosing program was stopped and replaced by a health education program. A follow-up abattoir and dog coproantigen survey in 1995 to 1996, however, indicated that E. granulosus infection had reemerged in sheep and dogs in the previous hydatid-control intervention areas. In 2001, the foot and mouth disease (FMD) epidemic in sheep in England and Wales affected some farms in both the former hydatid-intervention and nonintervention areas. Concern was raised that dog access to carcasses of sheep, euthanized as part of the FMD control program and awaiting incineration, could amplify the prevalence of infection in dogs and thereby the subsequent risk for humans. A third coproantigen survey of farm dogs in south Powys and north Gwent was therefore undertaken in 2002 to determine the prevalence of canine echinococcosis in the former hydatid-intervention and nonintervention areas.

Emerging Infectious Diseases
April 12, 2005

Original web page at Emerging Infectious Diseases

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Mining the canine genome

Man’s best friend, the dog, is proving that it has one more way to lend a helping paw. The identification of canine genes is not only improving the health of dogs, but is also helping researchers identify genes controlling human diseases and develop treatments. Dr. Dennis O’Brien, a professor of neurology at the University of Missouri’s College of Veterinary Medicine and an expert on neurodegenerative diseases, says he is thrilled about the recent identification of genes that cause two types of rare epilepsy in dogs and humans. “It’s very exciting. I think it shows the power of canine genomics to (be able) to start answering some of these questions,” Dr. O’Brien said.

Berge Minassian, MD, and other scientists at the Hospital for Sick Children in Toronto, turned to the dog in their hunt for genes that cause Lafora disease in humans. With Lafora, seizures begin in the teenage years and increase in frequency until they cause death, usually within five years after the onset of the first symptoms. The researchers had identified one gene in humans but knew there was at least a second gene, because some families couldn’t be linked to the first gene. “I knew that Lafora is, relatively, frequently reported in dogs,” Dr. Minassian said. “I thought perhaps if we found families of dogs (that) have this disease, it may help us find the gene and, from there, the human gene.”

Dogs with Lafora have myoclonic seizures, which are characterized by brief short jerks of a muscle or a group of muscles. Animals develop signs between the ages of six and nine, and death follows within three years. After learning that five percent of purebred miniature wirehaired Dachshunds in the United Kingdom suffered from Lafora, the Canadian researchers began collaborating with veterinary neurologists Dr. Clare Rusbridge at The Stone Lion Veterinary Centre in London and Dr. Sue Fitzmaurice at Wey Referrals in Surrey, England. Veterinarians from the United States and France also contributed.

In the Jan. 7, 2005, issue of Science, the investigators report that affected dogs carry two copies of a gene with an expansion mutation. These “stutters” or repetitions of base pairs have also been implicated in other neurodegenerative diseases, such as Huntington’s disease.
Scientists have developed a test so that breeders can identify dogs that carry the gene. Canadian researchers had continued their efforts to map the gene responsible for Lafora in humans and actually finished mapping the gene in dogs and humans at the same time. Nevertheless, the identification of the gene in dogs will greatly benefit human medicine. Mice don’t make good models for Lafora, in part, because their lives are too short. “The dog models the disease almost perfectly,” Dr. Minassian said. “In terms of when we start developing treatments, it is going to be great to have the dogs to treat first, before we try (a treatment) in humans. This applies not only to any kind of medication-type treatment, but if and when we are ready to do gene therapy.”

The canine genome also recently proved valuable in identifying a gene that causes neuronal ceroid-lipofuscinosis in humans, otherwise known as Batten’s disease. Over time, children with this disease suffer mental impairment, worsening seizures, and progressive loss of sight and motor skills. The disease is usually fatal in the late teens or 20s. In the 1950s, a Norwegian veterinarian identified an NCL-like disease in a group of related English Setters. Affected English Setters develop signs similar to Batten’s and die at approximately two years of age from intractable seizures. The canine disorder most closely resembles the juvenile form of Batten’s disease.

This past February, researchers at the University of Missouri-Columbia and Indiana University-Indianapolis announced in the journal Biochemical and Biophysical Research Communications that they had identified the gene involved in this type of epilepsy. The canine model will help scientists study the disease in humans; the genetic test will help breeders. “When the American Kennel Club surveys dog breeders about what diseases they consider the most pressing problems, epilepsy is always in the top five,” Dr. O’Brien said. “We hope these kind of genetic mapping studies will ultimately lead us to find the genes that are responsible for the more common forms of epilepsy.”

The two epilepsy genes are only the most recent success stories involving the canine genome. Scientists have identified genes for conditions including vision disorders, heritable kidney cancer, narcolepsy, severe combined immunodeficiency (often called bubble boy disease), cystinuria, and bleeding disorders. The narcolepsy gene is one example of how identifying a gene for a rare condition can uncover the molecular biology of common cellular processes. In 1999, researchers showed that a mutation in the HCRT2 gene caused narcolepsy in Doberman Pinschers.
This gene was found to affect hypocretin, a protein neuropeptide. Since then, further studies have proved that hypocretin deficiency is associated with most cases of narcolepsy in humans, and that hypocretin might have a key role in circadian clock-dependent alertness and in regulating metabolic rate, appetite, mood, and sleep.
Targeting hypocretin could lead to therapies for narcolepsy and more common sleep disorders.

According to Dr. Gustavo Aguirre, a professor of medical genetics and ophthalmology at the University of Pennsylvania School of Veterinary Medicine, almost half of the roughly 30 genes identified for diseases in dogs are for vision disorders. Scientists have even successfully used gene therapy to cure two of them, one being Leber congenital amaurosis. In humans, this condition causes vision loss starting in infancy. “We treated dogs, restored vision, and that (treatment) will be used to treat human patients, if that continues to be successful,” says Dr. Aguirre, who was involved in the study. He anticipates that phase I clinical trials for humans could begin at the end of 2005 or early 2006.

So why are researchers having such success? It is often easier to find a gene in a dog than in another mammal, because of breeding. Dog breeds are similar to geographically isolated human populations, which offers an advantage when tracking down genes. Nearly half of genetic diseases reported in dogs occur predominantly, or exclusively, in one or a few breeds. When genes are identified, the development of genetic tests allows dog breeders to reduce the incidence of disease. The first such test was developed in 1995 for progressive renal atrophy in Irish Setters. For some time, canine geneticists have understood the promise of the pooch to help human health.
The top 10 diseases of greatest concern in purebred dogs include several that are of concern to human health, among them, cancer, epilepsy, autoimmune diseases, heart disease, and diseases causing cataracts.

Elaine Ostrander, PhD, chief of the cancer genetics branch of the National Human Genome Research Institute, believes canine genome research could be particularly useful in studying cancer. “By using dogs as an animal model and comparing what we learn in them to what we know about human cancer, we are slowly but surely putting together the basic vocabulary of cancer susceptibility,” Dr. Ostrander says. She and others believe that we are seeing only a small hint of what is to come. Drafts of the canine genome, the first of which was published in 2003, will help researchers identify genes more quickly. “With the canine genome, we know what the normal sequence is in a normal dog, so it makes it much easier to then see (whether a) dog with a disease has the normal kind of gene or if there is something different,” Dr. O’Brien said. Subsequent drafts of the genome will provide more information.

Dr. Ostrander believes that, in the future, canine geneticists will turn their attention even to genes involved in behavior, such as obsessive-compulsive tail chasing seen in Bull Terriers, which could provide clues to human behavior. Other possibilities are separation anxiety, impulse control disorders, and even aggression. She cautions, however, that with this latter behavior, legal and social implications come into play.

Source: Kate O’Rourke

JAVMA
March 29, 2005

Original web page at JAVMA

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Scope of medical laser safety standard broadened

Lasers are being used more frequently than ever in veterinary medicine for declawing, spay-and-neuter surgery, tumor removal, oral and ear surgery, and other applications. For the first time, the national standard for safe laser use in health care facilities covers the document’s possible use by veterinarians. As the AVMA liaison representative to the American National Standards Institute’s Z136.3 Subcommittee, Dr. Kenneth Bartels worked with his counterparts from other professional groups to develop voluntary standards that ANSI can adopt. State authorities and the federal Occupational Safety and Health Administration often use ANSI guidelines as the basis for promulgating regulations. “An appendix to ANSI Z136.3 Safe Use of Lasers in Health Care Facilities now covers veterinary medicine and the use of lasers,” he said.

Dr. Bartels worked diligently to ensure that AVMA and the veterinary profession had input into the veterinary provisions so that others were not writing standards for veterinary medicine, and that they remained guidelines and were not restrictive. He explained that the medical profession was reluctant to open the standard development to veterinarians, fearing it would lead to involvement by nonprofessionals. In early 2003, Dr. Bartels sent the AVMA Council on Veterinary Service a draft of the veterinary provisions proposed for the Z136.3 appendices. The council forwarded them that May to the Executive Board for approval, which was granted. The laser information, included in the AVMA Guidelines for Hazards in the Workplace, states the following:

The use of lasers in Veterinary Medicine is becoming more common and it is paramount that the operator of the laser as well as the employer and all employees be thoroughly versed in the use and hazards of the use of the laser.
Laser equipment must be maintained properly and used appropriately for the type of equipment and type of procedure. Veterinarians are referred to the ANSI Z136.3 Standards amended in Appendix B-B17, “Use of Lasers in Surgical and other Medical Specialties.”
Veterinarians who have class 4 surgical lasers in their practice should obtain a copy of the standards, Dr. Bartels suggests. It is valuable for training new members of the practice staff, and it is a document to refer to in the event of a visit from an OSHA or state health inspector.
Dr. Bartels is the McCasland Foundation Laser Surgery Professor and holds the Cohn Family Chair at the College of Veterinary Medicine, Oklahoma State University. Until June, however, he is deployed by the Army Veterinary Corps as interim commander for the Northeast Atlantic region.

The rapid change in the pattern of use of health care laser systems was the driving force behind the revision of Z136.3. Most medical laser systems are now found in private medical offices. They have expanded into cosmetic uses in areas that may have limited or part-time medical supervision, such as spas and beauty salons. Not only has the environment of laser systems greatly broadened, but also, the training of the operators has become far more diverse. The Z136.3 standard represents many compromises to fit their varied needs. Government and voluntary professional agencies rely on the standard to guide them in regulating the use of medical laser systems that intentionally expose patients to their output for medical or cosmetic purposes.

JAVMA
March 29, 2005

Original web page at JAVMA

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The Environment Food and Rural Affairs Select Committee of the House of Commons (EFRACom) published its report on its pre-legislative scrutiny of the Animal Welfare Bill

The report gives general support to the principles of the Bill and especially the concept of a ‘duty of care’. EFRACom say that there is still a significant amount of work to be done before a Bill can be presented to parliament. The committee criticises the breadth of power the Bill proposes to leave in the hands of government as a result of the ability to introduce secondary legislation and says that the Bill should contain much more detail of what is proposed. EFRACom support the ban on cosmetic tail docking but accept that some prophylactic docking should be allowed subject to puppies being identified by microchip. They were clearly not aware of the limitations of micro chipping puppies a few days old. This discussion clearly has some way to run.

The report also criticises the manner in which regulation of pet fairs is proposed, the omission of any research on electric shock collars, the proposed regulation of sanctuaries and the proposed timescale for regulation of greyhound licensing. The definitions of the welfare offences are said to be unclear and the repeal of a specific offence of abandonment regretted. EFRACom also criticise the superficial nature of the Regulatory Impact Assessment, which they describe as ‘excessively simplistic’, and the lack of recent consultation on the Bill by DEFRA.

The critical nature of the report is likely to significantly delay publication of the Bill and therefore its introduction to parliament. Such a delay is likely to put the entire Bill in jeopardy if there is to be a general election in May 2005.

Source: Chris Laurence

BSAVA
March 15, 2005

Original web page at BSAVA