Deforestation and Emerging Infectious Diseases

Many are aware of the environmental consequences of deforestation: trees absorb carbon, and in a world of escalating carbon levels, this natural process is critical to the effort of slowing global warming. What is less well-known about deforestation, is the part it plays in public health for both humans and animals. In this article, Laura Kahn illustrates the role of deforestation in the spread of emerging infectious diseases among both humans and animals. She does this through the story of the Nipah virus outbreak in Malaysia, an event that continues to affect Southeast Asia both directly and indirectly. Kahn outlines the sequence of events that followed a mass deforestation in Malaysia in 1997, the focus of many studies concerning Nipah virus. Being forced from their natural habitat , tropical fruit bats began to feed from fruits in orchards through which pigs roamed and fed. It is through this exposure that an outbreak of the virus spread throughout the newly industrialized pig industry and consequently, to those humans involved in the industry. By 1999, the virus was isolated, the exportation of pigs from Malaysia was halted, about 1 million pigs were killed, 266 people contracted the disease, and 106 died soon after. The outbreak had enormous economic effects on the region, and outbreaks continue to occur, the latest reported being in Bangladesh (February 6, 2011).

http://thebulletin.org/web-edition/columnists/laura-h-kahn/deforestation-and-emerging-diseases

http://www.ncbi.nlm.nih.gov/pubmed/16329551

http://www.promedmail.org/pls/apex/f?p=2400:1202:2043200362336969::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,86975

MRSA: From Humans to Animals and back again and other concepts

We welcomed Dr. David Weber, Dr. Jorge Ferreira, and Dr. Vance Fowler on Tuesday, February 22, 2011, to our One Health Collaborative Intellectual Exchange Group meeting to discuss MRSA. Dr. Weber is a Professor of Medicine and Pediatrics and UNC’s School of Medicine and also a Professor of Epidemiology at UNC’s Gillings School of Global Public Health. He kicked off the session with great stories on how people become infected with infectious diseases and common sense ways to avoid infection. He was very adamant on the fact that lessons can lessons can be learned after every infection, no matter how large or small. It was interesting, that during his presentation, he noted that the country with the greatest number of newly emerging diseases were discovered in the United States, based on the sole fact that the United States has better technology than other countries for identifying these new and emerging zoonotic diseases. Dr. Ferreira is currently a Fulbright scholar in the Comparative Biomedical Sciences Ph.D. program at NCSU’s College of Veterinary Medicine, Department of Population Health and Pathobiology. He’s presentation focused on the unknown variables when organisms, humans or animals, become infected with MRSA. One of the major barriers at the moment is determining which organism was infected first, the human or the animal. A lengthy discussion followed addressing the concept of “community associated MRSA” in which one community becomes infected with one strand and another community becomes infected by a different strand. This highlighted some of the harder aspects of studying MRSA outside of clinical settings. His overall message was that this is no longer an individual’s problem, but a societal problem with the potential to involve all living things. A question and answer session followed in which Dr. Fowler contributed. Dr. Fowler was trained at Duke University and is currently an extensively published, Associate Professor. This was the first time the One Health Collaborative Intellectual Exchange Group had an extensive panel discussion session that followed the presentations. The questions asked varied from personal experiences with MRSA and specific risk factors, to ways in which local entrepreneurs are developing microbial resistant textiles, to ways in which individual medical practitioners can become more educated on patient symptoms and to follow the developments of MRSA research and finding.

We want to thank again Drs. Weber, Ferreira, and Fowler, for participating in the One Health Collaborative Intellectual Exchange Group. It is people like you who are ready and willing to share your comments, suggestions, and life experiences, that make the One Health Collaborative Intellectual Exchange Group a truly learning and positive experience.

Tick-transmitted Infectious Diseases In North Carolina: Local, National and Global Implications

Session 6 on 15-February 2011 was entitled “Tick-transmitted Infectious Diseases In North Carolina: Local, National and Global Implications”. The panel consisted of Dr. Ricardo Maggi, and Dr. Ed Breitschwerdt.

Dr. Maggi is Research Assistant Professor of Molecular Microbiology in the Department of Clinical Sciences at the College of Veterinary Medicine at North Carolina State University. He is also Chief Technical Officer and Assistant Director of Research and Development at Galaxy Diagnostics in RTP. Dr. Maggi’s topic of discussion was Borrelia in Ixodes ticks in North Carolina. Borrelia burgdoferi is the leading cause of Lyme disease.

According to Dr. Maggi, while 30-50% of Ixodes scapularis carry B. burgdoferi in New England, only 5% of I. scapularis do in Virginia. This figure drops to 0.3% in North Carolina. In contrast, among Ixodes affini ticks in North Carolina, 64% are infected with B. burgdoferi. This infection is more prevalent in female ticks than male ticks. 55% of male I. affini are infected while 77% of females are infected. Therefore, the epidemiology of B. burgdoferi infection in ticks appears to be different in North Carolina compared to the Northeastern states.

Dr. Ed Breitschwerdt is Professor of Medicine and Infectious Diseases at North Carolina State University College of Veterinary Medicine, Adjunct Professor of Medicine at Duke University Medical Center, and a Diplomate, American College of Veterinary Internal Medicine (ACVIM). Dr. Breitschwerdt discussed several tick-borne illnesses, including his groundbreaking research in Bartonella infections.

Dr Breitschwerdt started his talk by discussing how tick borne diseases are important because they can result in death. Ticks secrete toxins, which target lower motor neurons and cause paralysis. Paralysis can be generalized and cause death by affecting respiratory muscles. Dr Breitschwerdt then talked about dogs as sentinels for tick borne infections and the use of C6 ELISA methodology to detect canine infection with tick borne diseases.

According to Dr Breitschwerdt, Rocky Mountain Spotted Fever is the most important tick borne disease in North Carolina because it is potentially fatal. Features include fever, rash, gangrene and anemia. It is important that veterinarians not miss this diagnosis because a delayed or missed diagnosis can cause death in both animals and their human owners. Even though RMSF is usually thought of as a disease of the countryside, it has been found in places like New York City. After all, it only takes one tick to transmit the disease. Dr Breitschwerdt then proceeded to discuss other tick borne diseases like Ehrlichia, Anaplasma phagocytophilum and Bartonellaceae. Bartonellaceae is unique because it can infect multiple cells in the body, and is becoming an increasingly important cause of tick borne disease in the state. The vector that transmits Bartonella henselae is Ixodes ricinus. Animals are important reservoirs for the vectors.

A theme that Dr. Breitschwerdt returned to throughout his talk was that of the importance of having a high index of suspicion for tick borne illnesses and how every patient whom the veterinarian or physician suspects to have a tick borne illness should be treated with doxycycline. Other measures like removal of fleas and ticks from dogs are also important in preventing the risk of disease transmission.

Questions from students, faculty members, professionals, and attendees covered a wide range of topics:

• Could mandating tick prevention in dogs lessen tick-borne infections in humans?
• What are the possible reasons for the difference in the prevalence of Borrelia in Ixodes scapularis and Ixodes affinis?
• Given that most tick borne illnesses are treated with doxycycline, how does determining the differences in tick and pathogen epidemiology in North Carolina help change management and treatment of tick borne diseases?
• Do tick borne illnesses caused by different bacterial species (rickettsia, borrelia, bartonella) present similarly?
• Since tick borne illnesses affect both humans and their animal pets, is there much collaboration between physicians and veterinarians in managing this group of diseases?
  

The session concluded with a discussion of the need for collaboration and data sharing between veterinarians, physicians, public health professionals, and environmental scientists.

Russia's Fish Fight for Oxygen in St. Petersburg pond

Russia's Fish Fight For Oxygen In St. Petersburg Ponds (PHOTOS)

http://www.huffingtonpost.com/2011/02/11/russias-fish-fight-for-ai_n_822101.html#s238893&title=Russia_Winter_Fish

AP/The Huffington Post

ST. PETERSBURG, Russia (AP) — As the long Russian winter drags on, fish in the ponds of St. Petersburg become increasingly desperate for oxygen, clustering in vast, thrashing masses at shrinking holes in the ice.
Swimmers who brave the frigid temperatures for an invigorating dip find themselves stroking through swarms of fish that flock to the open water. The fish are so thick that humans can easily reach out and catch them with their hands.
Not only does ice block oxygen that could be diffused into the water from the air, but it also impedes sunlight from reaching oxygen-generating plants and algae in the water.
"The only way to help the fish in this situation is to make more holes in the ice," says Sergei Titov of St. Petersburg's Lakes and Rivers Fish Sector Institute.

Scientists probe big fish die-off

Scientists probe big fish die-off

http://www.windsorstar.com/technology/Scientists+probe+fish/4223336/story.html#ixzz1Dypa66Co

Tests are being done in Michigan to see why thousands of dead gizzard shad are turning up along the Detroit River and in lakes Erie and St. Clair.

"The only thing we're really sure of is temperatures are likely a factor," Ministry of Natural Resources biologist Andy Cook said Thursday from Wheatley.

Gizzard shad, at the northern end of their range here, are vulnerable to the cold and has been known to have large die-offs, Cook said.

Because there seemed to be more dead fish than usual, tests are being done through the Michigan Department of Natural Resources and Environment.

Department spokeswoman Mary Dettloff said the gizzard shad found in Lake St. Clair are being tested for a deadly fish virus called VHS because some of them showed symptoms of the disease.

Viral hemorrhagic septicemia is a viral disease found in freshwater and saltwater fish in Europe, Japan and along the coasts of North America. The disease was first identified in Ontario in 2005 in Lake Ontario. Since then it has caused large die-offs of fish. It has been found in a number of species including commercial and sport fish such as walleye and yellow perch.

It is not a threat to people who eat fish.

"We might see it in other species," Dettloff said of the disease, which causes fish to bleed internally.

"We'll keep a lookout for it this spring and summer."

On Jan. 20 a Windsor resident walking his dog along the Detroit River in Alexander Park saw thousands of dead fish. The MNR found thousands of dead gizzard shad farther east near Little River on Jan. 28.

Cook said they appeared to be juvenile fish about 15 centimetres long. Gizzard shad are silver and grow to about 25 centimetres as adults. They are not an important sport fish and serve as food for larger fish such as walleye.

Expect to see more dead gizzard shad this winter and spring as the ice melts, Dettloff said. Contributing to the large die-off is the early cold weather and the fact that there are a lot of young gizzard shad this year.

The Ministry of the Environment had been called about the dead fish but is not investigating because there was no evidence pollution was the cause

Malady deadly to bats found in North Carolina

Malady deadly to bats found in North Carolina (North Carolina, United States, North America)

Published by USFWS Southeast Region - www.fws.gov/southeast/news on 2/9/2011

White-nose syndrome, the disease that has killed hundreds of thousands of bats in the Eastern United States, has been discovered in a retired Avery County mine and in a cave at Grandfather Mountain State Park, marking the arrival of the disease in North Carolina.
“White-nose syndrome is confirmed in Virginia and Tennessee, so we expected we would be one of the next states to see the disease,” said Gabrielle Graeter, a biologist with the N.C. Wildlife Resources Commission. “This discovery marks the arrival of one of the most devastating threats to bat conservation in our time.”
Although scientists have yet to fully understand white-nose syndrome, current knowledge indicates it’s likely caused by a newly discovered fungus, Geomyces destructans , which often grows into white tufts on the muzzles of infected bats, hence the disease’s name. The first evidence of this fungus was collected in a New York state cave in 2006. Since then, it appears to have spread north into Canada and as far south as Tennessee, which reported its first occurrence last winter, and now North Carolina. In the Northeast, the disease has decimated some species of bats. It seems to be most fatal during the winter months, when hundreds of bats are hibernating together in caves and mines. It’s not known if the disease will similarly affect all species in all regions of the country, though bat mortality and the diversity of species affected in the Northeast suggest the impacts will be significant.
On Feb. 1, a team of Commission biologists were conducting a bat inventory of the closed mine where they saw numerous bats displaying symptomatic white patches of fungus on their skin. Five bats from the mine were sent to the Southeastern Cooperative Wildlife Disease Study unit at the University of Georgia for testing, which confirmed the presence of white-nose syndrome.
In late January, a team of state, federal, and private biologists were conducting a bat inventory of a cave at Grandfather Mountain when they discovered a single dead bat. Following state white-nose syndrome surveillance protocols, the bat was sent for testing and it has been confirmed for white-nose syndrome.
The discovery of white-nose syndrome comes as Commission biologists work through bat inventory and white-nose syndrome surveillance efforts at numerous caves and mines in western North Carolina this winter as part of a grant awarded by the Service to several states on the leading edge of the disease’s spread.
North Carolina is home to three federally endangered bats, the Virginia big-eared, Indiana, and gray. Virginia big-eared bats are known from the Grandfather Mountain cave and have been seen in the Avery county mine, though not recently. Thus far, the disease has not been observed in Virginia big-eared bats farther north, however it has greatly impacted Indiana bat populations at infected caves and mines. Both of the North Carolina sites have Eastern small-footed, little brown, Northern long-eared, and tri-colored bats while big brown bats are also found at the mine – all bat species that have been affected to some degree by white-nose syndrome in the Northeast.
“The discovery does not bode well for the future of many species of bats in western North Carolina,” said Sue Cameron with the U.S. Fish & Wildlife Service. “Although researchers are working hard to learn more about the disease, right now so little is known. There has been some evidence that humans may inadvertently spread the disease from cave to cave, so one simple step people can take to help bats is to stay out of caves and mines.”
“Cavers are passionate about what they do and we truly understand that asking them to stay out of caves is no small request and we greatly appreciate their sacrifice,” said Cameron, noting that the western North Carolina caving club, Flittermouse Grotto, has been very supportive of efforts to protect the area’s bats.
In 2009, fearing the disease could be transferred from cave to cave by humans, the Service released a cave advisory asking people to refrain from entering caves in states where white-nose syndrome has been confirmed and all adjoining states. The North Carolina Wildlife Resources Commission holds a protective easement on the mine and both it and the Grandfather Mountain cave have been gated and closed to the public for years to protect hibernating bats.
For more information about white-nose syndrome, visit http://www.fws.gov/whitenosesyndrome.

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Photos can be found at: http://www.flickr.com/photos/usfwssoutheast/sets/72157625882981881/

Review of One Health Intellectual Exchange 2011 Session 5 (Dr. Charles Rupprecht, Dr. Carl Williams, Dr. G. Robert Weedon, and Peter Costa)

On Tuesday, February 8^th 2011, we welcomed rabies virus experts Dr. Charles Rupprecht, Dr. Carl Williams, Dr. G. Robert Weedon, and Peter Costa to our One Health Collaborative Intellectual Exchange Group meeting to discuss the disease. Dr. Rupprecht was the first speaker of a four part presentation that promoted rabies awareness, management, and control from a series of domestic and global perspectives. He began with an informative background history of the virus as well as the United State’s role in laboratory-based surveillance of the disease. We also explored the necessary steps to eradicate rabies cost-effectively, and established that the solution lies in eliminating the virus at the vector source by vaccinating animals as opposed to humans. Dr. Williams provided a thorough explanation of how the North Carolina public health system takes the necessary precautions to regulate and control potential outbreaks. The NC Division of Public Health holds rabies in high priority for disease management and surveillance, alongside Tuberculosis, HIV/AIDS, and other infectious diseases. We discussed the state’s body of statutes to ensure all pets are vaccinated, as well as the standard procedure for animal observation and PEP administration in the event of an animal bite. Dr. Weedon then introduced the topic of rabies control in less developed countries. He illustrated two prime examples of rabies surveillance and regulation in the dog reservoir: Bohol, Phillipines and Jaipur, India. In both cases, rabies transmission to humans was lowered as a result of dog population control (sterilizations) and mass vaccination. In the Bohol intervention, a 70% vaccination of the dog population was found to be efficacious in controlling the spread of the virus. Our final presenter was Costa, who explained to us the greatest challenges in increasing rabies awareness worldwide. A lack of knowledge about the virus is the greatest global contributor to rabies mortality. Our mission should be preparing health systems with the capacity to distribute the resources to vaccinate animal populations, as well as educate the community on preventing disease transmission and recognizing outbreaks. In closing we discussed the significance of World Rabies Day in achieving One Health Initiative goals. World Rabies Day is an annual campaign founded by the global Alliance for Rabies Control that takes place on September 28^th. Its diverse community of partners has united under the common goal to “mobilize awareness and resources in support of human rabies prevention and animal rabies control”. Its homepage can be found at www.worldrabiesday.org . Special thanks to our guest speakers for sharing with us their past achievements and future goals in the fight against the rabies virus. It is imperative that even as we make progress in controlling the disease that we do not lose sight of its implications towards achieving One Health goals. Conquering rabies will require efforts from those aimed at improving the health of humans, animals, and the environment, making it an ideal target for the One Health Initiative and its affiliates.

Discussion questions from students and attendees:

Are there any transgenic or breeding (for rabies resistance) options to addressing the issue of rabies control? If so, what are the barriers and if not, is there research currently being done?

The elimination of dogs as a primary reservoir for rabies has largely been possible in North America and Western Europe because most dogs are domestic pets. How effective will rabies vaccination programs be in countries with large urban and rural populations of feral dogs (such as Southern Asia)?

According to the WHO position paper on rabies, intradermal administration of vaccines is a safe alternative to intramuscular injection, requiring only 1-2 vials of vaccine and low cost. If these programs are effective, why does the U.S. require intramuscular injections, higher doses, and much more expensive vaccine programs?