Ouch! Taking a Shot at Plague: Vaccine Offers Hope for Endangered Ferrets in Plague Outbreak

Endangered black-footed ferrets, like children, aren't exactly lining up to be stuck with a vaccine, but in an effort to help control an extensive outbreak of plague in South Dakota, some of the ferrets are getting dosed with a vaccine given by biologists.

This is the first time the vaccine has been used during a major plague epizootic—an animal version of a human epidemic. Sylvatic plague is an infectious bacterial disease usually transmitted from animal to animal by fleas. This exotic disease is usually deadly for black-footed ferrets and their primary prey, prairie dogs. Black-footed ferrets are one of the rarest mammals in North America.

In mid-May, the Centers for Disease Control confirmed sylvatic plague in black-tailed prairie dog colonies in the Conata Basin area of Buffalo Gap National Grasslands in southwestern South Dakota. As of late June, about 9,000 acres of prairie dog habitat — including colonies occupied by vulnerable black-footed ferrets — have been infected by the disease, according to U.S. Forest Service mapping. Black-tailed prairie dogs are also being reconsidered for listing under the Endangered Species Act.

Ferret population surveys in the fall of 2007, before the outbreak, indicated at least 290 ferrets lived in the Conata Basin ferret reintroduction area. Some of the plague-impacted prairie-dog colonies were occupied by ferrets, but researchers do not know yet how many ferrets have died from the outbreak. Scientists report that in the past, such outbreaks have wiped out entire colonies of prairie dogs and the black-footed ferrets that depended on them for food.

To help increase ferret survival during this outbreak, biologists are vaccinating wild ferrets to provide immunity if they become exposed to plague. The plague vaccine was developed for humans by the U.S. Army Medical Research Institute for Infectious Disease and is being tested and modified for animals at the USGS National Wildlife Health Center (NWHC) in Madison, Wisc.

Ferret getting vaccinated at the USGS National Wildlife Health Center (courtesy USGS)

Spraying insecticide in prairie-dog colony (courtesy USFWS)

Black-footed ferret poking its head out of a prairie-dog burrow (courtesy USFWS)

"Although the plague vaccine is still experimental in wildlife, we hope its use during this epizootic will protect as many ferrets as we can capture in the field and boost ferret survival during this critical period," said USGS NWHC Research Chief Dr. Christopher Brand.

Prairie Wildlife biologists working with the federal agencies have captured and vaccinated 40 black-footed ferrets since the outbreak began, said Scott Larson with the U.S. Fish and Wildlife Service, who is coordinating measures to conserve ferrets among the federal agencies.

Dr. Tonie Rocke, the lead researcher at the USGS NWHC testing the vaccine for animals, said the vaccine is administered to prairie dogs and black-footed ferrets through an initial shot and a booster about a month later. She noted that the NWHC is working on a separate oral vaccine for prairie dogs that can be put into bait and delivered in the field without having to handle the animals, a process that is time-consuming.

Another strategy to control plague outbreaks is to apply insecticide that will reduce the flea populations in the prairie dog colonies that are important to black-footed ferrets, but that have not yet experienced plague die-offs.

Dr. Dean Biggins, a research ecologist and black-footed ferret expert at the USGS Fort Collins Science Center in Colorado, is collaborating with the NWHC to investigate the combined efficacy of dusting burrows with insecticide and vaccinating animals in the field. "We've had experience with burrow dusting in other areas, and we know dusting protects both species from plague during these outbreaks," Biggens said.

Field tests, said Biggins, showed that the combination of burrow dusting and experimental vaccine protected black-footed ferrets in Montana during a time of low-level plague mortality in the area.

"What we're trying to do in South Dakota is assess the protectiveness of the vaccine for prairie dogs and ferrets during a full-blown eruption of plague that is causing high mortality in the prairie dog population," Biggins said. About 75 prairie dogs were experimentally vaccinated in 2007 in South Dakota, and vaccination is continuing in 2008.

The U.S. Fish and Wildlife Service, U.S. Geological Survey, Animal and Plant Health Inspection Service, National Park Service, and the U.S. Forest Service are working together to lessen the impacts of this outbreak, as are private organizations such as Prairie Wildlife Research and conservation groups, including World Wildlife Fund, Defenders of Wildlife, and the Prairie Dog Coalition.

The same bacterium that affects ferrets, prairie dogs, and other rodents, is also responsible for human cases of plague. The disease is transmitted from animals to humans by bites of infected fleas, but it can be cured with antibiotics if treatment is prompt. About 5 to 15 people are infected by plague each year, and it is not unusual to have some human fatalities as a result. Last November, a National Park Service biologist contracted plague from a cougar and died.

New Approach Sheds Light on Ways Circadian Disruption Affects Human Health

Growing evidence indicates that exposure to irregular patterns of light and darkness can cause the human circadian system to fall out of synchrony with the 24-hour solar day, negatively affecting human health — but scientists have been unable to effectively study the relationship between circadian disruptions and human maladies.

The Daysimeter, shown above, measures an individual’s daily rest and activity patterns, as well as exposure to circadian light — short-wavelength light, particularly natural light from the blue sky, that stimulates the circadian system. Photo Credit: Rensselaer/Dennis Guyon

A study by researchers in Rensselaer Polytechnic Institute’s Lighting Research Center (LRC) provides a new framework for studying the effects of circadian disruption on breast cancer, obesity, sleep disorders, and other health problems.

Light and dark patterns are the major synchronizer of circadian rhythms — the biological cycles that repeat approximately every 24 hours — to the solar day. Inadequate or irregular light exposure can cause circadian rhythm disruptions that are believed to manifest into a variety of health ailments. However, ecological studies to measure human light exposure are virtually nonexistent, making it difficult to determine if, in fact, light-induced circadian disruption directly affects human health.

LRC researchers have created a small, head-mounted device to measure an individual’s daily rest and activity patterns, as well as exposure to circadian light — short-wavelength light, particularly natural light from the blue sky, that stimulates the circadian system. The device, called the Daysimeter, was sent to 43 female nurses across the country to measure their daily exposure to circadian light, according to Mark Rea, director of the LRC and principal investigator on the project.

The Daysimeter was worn for seven days by both day-shift and rotating shift nurses and then returned to the LRC for analysis. Simultaneously, Rea and his colleagues studied the effect of irregular light exposure to the circadian system of 40 rats, in order to determine if the relationship between circadian disruption and health outcomes could be uncovered using rodent models.

Twenty rats were exposed to a consistently repeating pattern of 12 hours of light followed by 12 hours of dark, to mimic the light exposure experienced by day-shift workers. The remaining rodents were exposed to irregular 12-hour patterns of light and darkness.

For the nurses, circadian entrainment and disruption was measured by comparing exposure light and darkness with each individual’s rest and activity patterns. Wheel running was used to measure rat rest and activity patterns.

A quantitative measure of circadian behavioral entrainment or disruption for day-shift and rotating shift workers was developed based on the circular cross-correlations of activity and light exposure data from both the nurses and the rats. An analysis technique commonly utilized in the field of signal processing, circular cross-correlation involves the concept of time-shifting one signal relative to another to determine relationships between signals that might otherwise be obscured due to timing differences.

“We found that the circadian entrainment and disruption patterns for day-shift and rotating shift nurses were remarkably different from each other, but remarkably similar to the patterns for the two parallel groups of nocturnal rodents,” says Rea. “The marked differences within species, together with the marked similarities across species, in addition to the new method of quantifying circadian entrainment or disruption suggests that health-related problems associated with circadian disruption in humans can be parametrically studied using animal models.”

“This ability to quantitatively define circadian light and dark for humans and for animals will allow a new class of meaningful studies of light as a stimulus for circadian entrainment or disruption to be undertaken, not only in humans, but in nocturnal rodents as well – which, until now, has been impossible,” says Rea. “Additionally, studies of circadian disruption employing animal models for human disease can now be designed and conducted to more accurately reflect their relevance to the actual living conditions in humans.”

Rea carried out his research with LRC researchers Andrew Bierman, Mariana Figueiro, and John Bullough, who are co-authors on the paper. The study is published online in the Journal of Circadian Rhythms and can be viewed in its entirety at: http://www.jcircadianrhythms.com/content/6/1/7.

This project was funded by a grant from the National Institutes of Health’s Genes, Environment, and Health Initiative.

About the Lighting Research Center
The Lighting Research Center (LRC) is part of Rensselaer Polytechnic Institute of Troy, N.Y., and is the leading university-based research center devoted to lighting. The LRC offers the world’s premier graduate education in lighting, including one- and two-year master’s programs and a Ph.D. program. Since 1988 the LRC has built an international reputation as a reliable source for objective information about lighting technologies, applications, and products. The LRC also provides training programs for government agencies, utilities, contractors, lighting designers, and other lighting professionals. Visit www.lrc.rpi.edu.

About Rensselaer
Rensselaer Polytechnic Institute, founded in 1824, is the nation’s oldest technological university. The university offers bachelor’s, master’s, and doctoral degrees in engineering, the sciences, information technology, architecture, management, and the humanities and social sciences. Institute programs serve undergraduates, graduate students, and working professionals around the world. Rensselaer faculty are known for pre-eminence in research conducted in a wide range of fields, with particular emphasis in biotechnology, nanotechnology, information technology, and the media arts and technology. The Institute is well known for its success in the transfer of technology from the laboratory to the marketplace so that new discoveries and inventions benefit human life, protect the environment, and strengthen economic development.

New Paper Addresses Myths, Realities of Government Retiree Health-Care Crisis

While some states are taking adequate steps to address the cost of retiree health-care benefits, others – including New Jersey, New York, California and North Carolina – are facing tens of billions of dollars in so-called "unfunded liabilities." The myths and realities of this potential crisis are laid out in a new issue brief written by Dr. Robert Clark, a professor of economics and of management, innovation and entrepreneurship at North Carolina State University, and released by the Center for State and Local Government Excellence.

The paper, The Crisis in State and Local Government Retiree Health Benefit Plans: Myths and Realities, examines the current financial status of state retiree health plans from around the country. States with the lowest unfunded liabilities include North Dakota, Wyoming, Iowa and Oregon.

The brief finds that:

• Although there are widespread reports of a major fiscal crisis, the reality is that some states face a fiscal crisis while others do not.

• There are substantial differences in the total liabilities of state retiree health plans, depending on the generosity of the plan and the size of the public sector.

• Retirement benefits are not protected by state laws or constitutions, and public sector employers will continue to amend their plans to reduce costs.

For a copy of the full brief, visit the Web at http://tinyurl.com/5rfyw2

The Center for State and Local Government Excellence helps state and local governments become knowledgeable and competitive employers so they can attract and retain a talented and committed workforce. The center identifies best practices and conducts research on competitive employment practices, workforce development, pensions, retiree health security, and financial planning.

Using Magenetic Nanoparticles to Combat Cancer

Scientists at Georgia Tech have developed a potential new treatment against cancer that attaches magnetic nanoparticles to cancer cells, allowing them to be captured and carried out of the body. The treatment, which has been tested in the laboratory and will now be looked at in survival studies, is detailed online in the Journal of the American Chemical Society.

Magnetic Nanoparticles Capture Ovarian Cancer Cells
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"We've been able to use magnetic nanoparticles to capture free-floating cancer cells and then take them out of the body,” said John McDonald, chair of the School of Biology at Georgia Tech and chief research scientist at the Ovarian Cancer Institute. “This technology may be of special importance in the treatment of ovarian cancer where the malignancy is typically spread by free-floating cancer cells released from the primary tumor into the abdominal cavity.”

The idea came to the research team from the work of Ken Scarberry, a Ph.D. student in Tech’s School of Chemistry and Biochemistry. Scarberry originally conceived of the idea as a means of extracting viruses and virally infected cells when his advisor, Chemistry professor John Zhang, had another idea. He asked if the technology could be applied to cancer. Scarberry suggested it might be an effective means of preventing cancer cells from spreading.

They began by testing the therapy on mice. After giving the cancer cells in the mice a fluorescent green tag and staining the magnetic nanoparticles red, they were able to apply a magnet and move the green cancer cells to the abdominal region.
“If the therapy is able to pass further tests that show it can prevent the cancer from spreading from the original tumor,” Scarberry said, “it could be an important tool in cancer treatment.”
This technology holds more promise than solely using antibodies to fight cancer because there seems to be less potential for the body to develop an immune response due to the unique peptide-targeting strategy, and the composition of the magnetic nanoparticles.

"If you modify the nanoparticle and target it directly to the tumor cells using a small peptide, you are less likely to generate an undesirable immune response and more accurately target the cells of interest,” said Research Scientist Erin Dickerson.

In addition to testing magnetic nanoparticles, the research team is collaborating with other groups at Georgia Tech to determine how peptide-directed gold nanoparticles and nanohydrogels might also be used in fighting cancer.

Largest review of office-based plastic surgery confirms safety in accredited facilities

Mortality rate less than 1 percent in over 1.1 million procedures

ARLINGTON HEIGHTS, Ill. –A study examining plastic surgery procedures performed in accredited outpatient facilities found that office-based surgery is as safe as surgery performed in hospitals. The study published in July's Plastic and Reconstructive Surgery® (PRS), the official medical journal of the American Society of Plastic Surgeons (ASPS), reviewed more than 1.1 million procedures and found the mortality rate to be significantly less than one percent or 0.002 percent.

"The study shows that plastic surgery in accredited facilities is safe and deaths are rare," said ASPS Member Surgeon Geoffrey Keyes, MD, study co-author. "However, people should consider plastic surgery with the same seriousness as medically necessary surgery. Most importantly, patients should have their procedure performed by an ASPS Member Surgeon in an accredited facility."

The study reviewed data collected from January 2001 through June 2006 by The American Association for Accreditation of Ambulatory Surgery Facilities (AAAASF), which mandates biannual reporting of all complications and fatalities. The data was obtained from facilities accredited by the AAAASF, which requires that surgeons be board-certified and have credentials at a hospital to perform any procedure being contemplated at an office-based facility. The ASPS requires all of its Member Surgeons to operate only in accredited or licensed facilities.

The study found deaths occurring at office-based surgery facilities are rare. More than 1.1 million operative procedures in AAAASF-accredited office-based outpatient surgery centers were studied from 2001-2006. Deaths were infrequent, occurring 2.02 in 100,000 procedures or 0.002 percent, which is comparable to the overall risk of such procedures performed in hospital surgery facilities. The vast majority of deaths were due to pulmonary embolism (a blood clot that travels to the lungs, blocking major blood vessels). Pulmonary embolism is an uncommon cause of death associated with any type of surgery whether elective or medically necessary.

These new findings contribute to a growing safety record for office-based surgery procedures. A 2004 PRS journal study examined 400,000 operative procedures in AAAASF-accredited office-based outpatient surgery centers from 2001-2002 and found that death occurred in 1 in 59,000 procedures or 0.0017 percent.

"While all surgery carries risks, the bottom line is that this study illustrates patients can and should feel safe when they go to an ASPS Member Surgeon who performs their procedures in an accredited facility," said ASPS President Richard D'Amico, MD. "Amazingly, only 14 states mandate accreditation of facilities, so it's up to the patient to be knowledgeable. A patient's safety and life is everything."

Nearly 11.8 million cosmetic surgery procedures were performed in 2007, up 59 percent since 2000, according to ASPS statistics. Fifty-nine percent of cosmetic surgery procedures were performed in an office-based facility, 21 percent in a free-standing ambulatory surgical facility, and 20 percent in a hospital.

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The American Society of Plastic Surgeons is the largest organization of board-certified plastic surgeons in the world. Representing more than 6,700 physician members, the Society is recognized as a leading authority and information source on cosmetic and reconstructive plastic surgery. ASPS comprises more than 90 percent of all board-certified plastic surgeons in the United States. Founded in 1931, the Society represents physicians certified by The American Board of Plastic Surgery or The Royal College of Physicians and Surgeons of Canada.

Booster vaccination may help with possible future avian influenza pandemic

New evidence suggests that a booster vaccination against H5N1 avian influenza given years after initial vaccination with a different strain may prove useful in controlling a potential future pandemic. The study is published in the August 1 issue of The Journal of Infectious Diseases, now available online.

H5N1 continues to pose a major health risk to birds and humans. As of mid-June, more than 60 percent of the more than 380 human cases have been fatal, and hundreds of millions of birds have died or been culled to prevent the spread of the disease. Should the virus evolve making human-to-human transmission more likely, a destructive global influenza pandemic could result.

The cornerstone of planning for such a possible pandemic is the development and distribution of effective vaccines. Several vaccines have been developed, but as the virus continues to mutate into genetically distinct lineages, or clades, the problem arises as to whether vaccines based on an older clade will be effective against newer versions. The new study is the first to report that giving one dose of a newer-clade vaccine to those who were vaccinated previously with older versions is more effective than giving only doses of the newer vaccine to unvaccinated subjects.

The study, conducted by Nega Ali Goji, MD, and colleagues from New York, Maryland, and Alabama, gave a single booster dose of a vaccine based on a clade 1 H5N1 virus circulating in Vietnam in 2004 to subjects who eight years earlier had received two doses of a vaccine based on the original, clade 0 virus that appeared in Hong Kong in 1997. Sixty-four percent had a positive immune response, which compares favorably to the results of a previous study using two doses of the clade 1 Vietnam virus, in which only 43 percent of those vaccinated had a positive immune response.

The results not only support the booster technique, but also show that even though the virus had mutated since the initial vaccination, using it to boost an earlier vaccine is more effective than simply vaccinating subjects with the most current vaccine. These findings are important given the fact that influenza viruses are mutating constantly.

"These results suggest that one strategy for pandemic control could involve prevaccination of some segments of the population prior to the emergence of a pandemic so that effective protection could be achieved with a single dose schedule if and when a pandemic emerges," the authors wrote. "If the finding that priming can result in enhanced responses to single-dose vaccination schedules were confirmed, then pre-pandemic vaccination programs could be considered, especially in populations of first responders, health care workers, or the military. Such populations might then be able to be effectively and rapidly vaccinated with a single dose of a vaccine specific for an emerging pandemic if it were to occur."

In an accompanying editorial, Gregory A. Poland, MD, of the Mayo Clinic College of Medicine, noted that some are already looking to begin such prevaccination primers against H5N1 influenza. For example, Japan is planning to immunize health care workers starting in 2009, and the U.S. Department of Defense is offering a vaccine to those in high risk specialties.

Dr. Poland pointed out that new studies are needed to investigate different types of vaccine administration, deal with vaccinations that prevent death but not infection and illness, search for more broadly cross-protective influenza vaccines, and collect data on the vaccination of those who are not healthy adults. Although, he said, "determining who should receive these vaccines, when, and in what order and under what circumstances deserves widespread debate," he agrees that the findings of the study are novel, as they "suggest that such a prime-boost strategy using vaccines derived from different H5 clades, separated by years, may be worthwhile, immunologically feasible, and safe."

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Fast Facts

1) Experts are concerned about a possible pandemic of H5N1 influenza. As of mid-June, 60 percent of the more than 380 human cases have been fatal, and half a billion birds have died or been culled to prevent the spread of the disease. Should the virus evolve making human-to-human transmission more likely, a destructive global influenza pandemic could result.

2) Giving a "booster" vaccine using a recent strain of virus to those previously vaccinated with an older strain was more effective than only vaccinating with the recent strain. Especially relevant is the fact that the primer and booster vaccines were derived from different strains of the virus and still were effective.

Founded in 1904, The Journal of Infectious Diseases is the premier publication in the Western Hemisphere for original research on the pathogenesis, diagnosis, and treatment of infectious diseases; on the microbes that cause them; and on disorders of host immune mechanisms. Articles in JID include research results from microbiology, immunology, epidemiology, and related disciplines. JID is published under the auspices of the Infectious Diseases Society of America (IDSA). Based in Arlington, Va., IDSA is a professional society representing more than 8,000 physicians and scientists who specialize in infectious diseases. For more information, visit www.idsociety.org.

Psychological and social issues associated with tooth loss

Expert shares ways to cope with the impact of losing teeth

ORLANDO (July 16, 2008)—Are feelings of depression overwhelming you? Is your self-esteem an issue? Having problems advancing in life or your career? Maybe you feel nervous or self conscious in social settings? Do you avoid social settings all together? Check your smile; tooth loss could be the culprit and you're not alone. Nearly 20 million teeth are extracted each year leaving scores of people to deal with the psychological affects of a less than perfect smile. However, during the Academy of General Dentistry's (AGD) 56th Annual Meeting & Exhibits in Orlando, Fla., July 16-20, H. Asuman Kiyak, PhD, will address the psychological issues affecting people who must deal with the loss of a tooth, as well as explain how this loss can affect the quality of life.

In Dr. Kiyak's course, "Enhancing the Oral Health and Quality of Life for Partially Edentulous or Fully Edentulous Patients: The Importance of Communication," she will reveal the post traumatic effects a patient endures after the loss of a tooth and will also pinpoint ways a doctor can communicate with a patient to help them cope with and understand their options for restoring their smile.

"The major impact of tooth loss is on the appearance and social relations component of quality of life because people cannot change their appearance with missing teeth," says Dr. Kiyak.

In fact, recent results from a survey distributed to nearly 20,000 AGD members revealed that more than 86 percent of general dentists reported social embarrassment is one of the greatest problems associated with tooth loss and more than half of these patients avoid social interaction because of it.

Yet, Dr. Kiyak noted that there are ways that patients can learn how to cope with the loss of a tooth. Dr. Kiyak encourages patients to:

• Weigh their options with the pros and cons for replacement teeth or even endodontic treatment to save a "hopeless" tooth.

• Review videos or still photos of others who have lost teeth and their current teeth status with removable or implant-supported dentures.

• Read testimonials of others who have undergone single, multiple, total tooth loss and replacement of these teeth with removable or implant-supported dentures, how they have coped with each stage and how they are functioning orally, systemically and psychologically with these dentures.

"A smile serves as an individual's most powerful tool," says AGD spokesperson Laura Murcko, DMD. "A great smile can make a great lasting impression, boost a person's self-esteem and confidence as well as improve their overall health."

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Dr. Kiyak will be one of more than 100 speakers that will present the latest developments in oral health and technology during the AGD's Annual Meeting & Exhibits. Dr. Kiyak's course will be held on Thursday, July 17 from 1:00 p.m. to 4:00 p.m. EDT.

About the AGD

The AGD is a professional association of more than 35,000 general dentists dedicated to staying up-to-date in the profession through continuing education. Founded in 1952, the AGD has grown to become the world's second largest dental association, which is the only association that exclusively represents the needs and interests of general dentists.

More than 786,000 persons are employed directly in the field of dentistry. A general dentist is the primary care provider for patients of all ages and is responsible for the diagnosis, treatment, management, and overall coordination of the general dentist through financial support of scientific, educational services related to a patient's oral health.

For more information about the AGD, please visit www.agd.org.

Dentists will be available for interviews about this topic, and/or other oral health topics, prior to and during the Annual Meeting which takes place July 16-July 20, 2008. Please contact Joshauna Walker at 312.440.4974 or media@agd.org.