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A new biosensor developed at the Georgia Tech Research Institute (GTRI) can detect avian influenza in just minutes. In addition to being a rapid test, the biosensor is economical, field-deployable, sensitive to different viral strains and requires no labels or reagents.

This kind of technology could be applied to real time monitoring of other diseases as well.

Photograph of the optical biosensor that is approximately 16 millimeters by 33 millimeters in size. The horizontal purple lines are the channels on the waveguide. Credit: Gary Meek

“We can do real-time monitoring of avian influenza infections on the farm, in live-bird markets or in poultry processing facilities,” said Jie Xu, a research scientist in GTRI’s Electro-Optical Systems Laboratory (EOSL)

The biosensor is coated with antibodies specifically designed to capture a protein located on the surface of the viral particle. For this study, the researchers evaluated the sensitivity of three unique antibodies to detect avian influenza virus.

The sensor utilizes the interference of light waves, a concept called interferometry, to precisely determine how many virus particles attach to the sensor’s surface. More specifically, light from a laser diode is coupled into an optical waveguide through a grating and travels under one sensing channel and one reference channel.

Researchers coat the sensing channel with the specific antibodies and coat the reference channel with non-specific antibodies. Having the reference channel minimizes the impact of non-specific interactions, as well as changes in temperature, pH and mechanical motion. Non-specific binding should occur equally to both the test and reference channels and thus not affect the test results.

An electromagnetic field associated with the light beams extends above the waveguides and is very sensitive to the changes caused by antibody-antigen interactions on the waveguide surface. When a liquid sample passes over the waveguides, any binding that occurs on the top of a waveguide because of viral particle attachment causes water molecules to be displaced. This causes a change in the velocity of the light traveling through the waveguide.

Five evolutionary stages of pathogen progression from animals to human transmission have been identified A proposed monitoring system of viral chatter has been proposed to provide warning of new diseases before they spread to humans.

In 1999, Wolfe began field work in the jungles of Cameroon to track “viral chatter,” or the regular transmission of diseases from animals to people, usually without further spread among humans. By monitoring the habits and the blood pathologies of bushmeat hunters and their kills, Wolfe and his team have identified at least three previously unknown retroviruses from the same family as HIV, as well as promoted safe practices for handling animals and animal carcasses.

“The Cameroon project demonstrated that it’s possible to collect information on viral transmission under very difficult circumstances from these highly exposed people,” Wolfe said.

With Cameroon as a prototype and a $2.5 million National Institutes of Health Pioneer Award as seed money, Wolfe has gone on to create a network of virus-discovery projects that monitor hunters, butchers, and wildlife trade and zoo workers in some of the world’s most remote viral hotspots. The network of a dozen sites in China, the Democratic Republic of Congo, Malaysia, Laos, Madagascar and Paraguay include source locations for such emerging diseases as SARS, avian flu, Nipah, Ebola and monkeypox.

There are more details of the five stages and a proposed study of the detailed origins of disease.

Wolfe and his colleagues begin by identifying five intermediate stages through which a pathogen exclusively infecting animals must travel before exclusively infecting humans. The research team identifies no inevitable progression of microbes from Stage 1 to Stage 5 and notes that many microbes remain stuck at a specific stage. The journey is arduous, and pathogens rarely climb through all five stages:

Stage 1. Agent only in animals: A microbe that is present in animals but not detected in humans under natural conditions. Examples include most malarial plasmodia.

Stage 2. Primary infection: Animal pathogens that are transmitted from animals to humans as a primary infection but not transmitted among humans. Examples include anthrax, rabies and West Nile virus.

Stage 3. Limited outbreak: Animal pathogens that undergo only a few cycles of secondary transmission among humans so that occasional human outbreaks triggered by a primary infection soon die out. Examples include the Ebola, Marburg and monkeypox viruses.

Stage 4. Long outbreak: A disease that exists in animals and has a natural cycle of infecting humans by primary transmission from the animal host but that also undergoes long sequences of secondary transmission between humans without involvement of animals. Examples include Chagas disease, yellow fever, dengue fever, influenza A, cholera, typhus and West African sleeping sickness.

Stage 5. Exclusive human agent: A pathogen exclusive to humans that involves either an ancestral pathogen present in a common ancestor of chimps and humans or involves a more recent pathogen that evolved into a specialized human pathogen. Examples include HIV, measles, mumps, rubella, smallpox and syphilis.

In addition, the team examines 25 diseases of important historic consequence to humans. Of the 25 diseases, 17 impose the heaviest world burden today: hepatitis B, influenza A, measles, pertussis, rotavirus A, syphilis, tetanus, tuberculosis, AIDS, Chagas disease, cholera, dengue hemorrhagic fever, East and West African sleeping sicknesses, falciparum and vivax malarias, and visceral leishmaniasis.

Eight more imposed heavy burdens in the past but have been reined in or eradicated thanks to modern medicine and public health practices: temperate diphtheria, mumps, plague, rubella, smallpox, typhoid, typhus and tropical yellow fever. Except for AIDS, dengue fever and cholera, most of the 25 have been important for more than two centuries.

The research team considered the varied pathologies of diseases originating in temperate (15) versus tropical (10) regions, as well as differing pathogen and geographic origins. Among the conclusions:

– Most of the temperate diseases, but none of the tropical diseases, are so-called “crowd epidemic diseases,” occurring locally as a brief epidemic and capable of persisting regionally only in large human populations. Most of the diseases originating in temperate climates convey long-lasting immunity.

– Eight of the 15 temperate diseases probably or possibly reached humans from domestic animals, three more from apes or rodents, and the other four came from still unknown sources. Thus the rise of agriculture, starting 11,000 years ago, plays multiple roles in the evolution of animal pathogens into human pathogens.

– Most tropical diseases have originated in wild, non-human primates. These animals are most closely related to humans and thus pose the weakest species barriers to pathogen transfer.

– Animal-derived human pathogens virtually all arose from pathogens of other warm-blooded vertebrates plus, in two cases, birds.

– Nearly all of the 25 major human pathogens originated in the Old Word (Africa, Europe and Asia), facilitating the conquest of the New World. Chagas disease is the only one of the 25 that clearly originated in the New World, while the debate is unresolved for syphilis and tuberculosis.

–Far more temperate diseases arose in the Old World because far more animals that furnish ancestral pathogens were domesticated there. Far fewer tropical diseases arose in the New World because the genetic distance is greater between humans and primates in this part of the globe.

The conclusions of the review illustrate large gaps in the understanding of the origins of even established major infectious diseases. Almost all studies reviewed were based on specimens collected from domestic animals, plus a few wild animal species.

The researchers propose an “origins initiative” aimed at identifying the origins of a dozen of the most important human infectious diseases as well as a global early warning system to monitor pathogens emerging from animals to humans.

This work is relevant to the lifeboat bioshield

If humanity ever meets lifeforms beyond Earth (or discovers our solitude in our galaxy) one thing will be sure–galactic historians will remark how interesting it must have been living in the nuclear age that “we now enjoy” (assuming we survive of course).

Speaking of nuclear, it seems that some scientists are utilizing a new drug that is showing major promises of fighting against radiation exposure, ensuring that victims not only survive, but remain “semi-healthy” as well.

(Space War) But now researchers at Washington University School of Medicine in St. Louis report they have developed an agent that protects cells from the lethal effects of radiation, regardless of whether it is given before or after exposure.

Using this agent in mice, the investigators found that the treatment helped shield rapidly dividing cells that are most vulnerable to radiation-induced death, providing proof in principle that it is possible to fend off radiation damage, according to a study published in the April issue of Biochemical and Biophysical Research Communications.

The interesting aspect of this drug is that it can be applied not only before a potential radiation calamity, but afterwards as well. Despite the fact that this drug is intended for those living on our home world, this anti-radiation drug could enable us to actually live upon the lunar and Martian surface.

Although this drug is not a “cure all” for all of our radiation woes, it could represent the first step of us actually living upon other worlds.

In a report to be published in the peer-reviewed journal PLoS Computational Biology and currently available online, Sally Blower, a professor at the Semel Institute for Neuroscience and Human Behavior at UCLA, and Romulus Breban and Raffaele Vardavas, postdoctoral fellows in Blower’s research group, used novel mathematical modeling techniques to predict that current health policy — based on voluntary vaccinations — is not adequate to control severe flu epidemics and pandemics unless vaccination programs offer incentives to individuals.

According to the researchers, the severity of such a health crisis could be reduced if programs were to provide several years of free vaccinations to individuals who pay for only one year. Interestingly, however, some incentive programs could have the opposite effect. Providing free vaccinations for entire families, for example, could actually increase the frequency of severe epidemics. This is because when the head of the household makes a choice — flu shots or no flu shots — on behalf of all the other household members, there is no individual decision-making, and adaptability is decreased.

While other models have determined what proportion of the population would need to be vaccinated in order to prevent a pandemic, none of these models have shown whether this critical coverage can actually be reached. What has been missing, according to Blower, a mathematical and evolutionary biologist, is the human factor.

The human factor involves two biological characteristics, “memory and how adaptable people can be,” Blower said. “These characteristics drive human behavior.”

The model Blower’s team developed is inspired by game theory, used in economics to predict how non-communicating, selfish individuals reach a collective behavior with respect to a common dilemma by adapting to what they think are other people’s decisions. The group modeled each individual’s strategy for making yearly vaccination decisions as an adaptive process of trial and error. They tracked both individual-level decisions and population-level variables — that is, the yearly vaccine coverage level and influenza prevalence, where prevalence is defined as the proportion of the population that is infected. The individual-level model was based on the human biological attributes of memory and adaptability.

The Lifeboat Foundation has the bioshield project

Cities that quickly closed schools and discouraged public gatherings had fewer deaths from the great flu pandemic in 1918 than cities that did not, researchers reported on Monday. Experts agree that a pandemic of some virus, most likely influenza, is almost 100 percent certain. What is not certain is when it will strike and which virus it will be.

In Kansas City, no more than 20 people could attend weddings or funerals. New York mandated staggered shifts at factories. In Seattle, the mayor told people to wear face masks.

No single action worked on its own, the researchers found, it was the combination of measures that saved lives. Peak death rates can be 50% to eight times lower. St. Louis authorities introduced “a broad series of measures designed to promote social distancing” as soon as flu showed up. Philadelphia downplayed the 1918 flu.

Philadelphia ended up with a peak death rate of 257 people per 100,000 population per week. St. Louis had just 31 per 100,000 at the peak.

No good vaccine would be available for months, and drugs that treat influenza are in very short supply.

So experts are looking at what they call non-pharmacologic interventions — ways to prevent infection without drugs. They hope this can buy time while companies make and distribute vaccines and drugs.

Because the virus is spread by small droplets passed within about three feet (1 meter) from person to person, keeping people apart is considered a possible strategy.

The U.S. government flu plan calls for similar measures, including allowing employees to stay home for weeks or even months, telecommuting and closing schools and perhaps large office buildings.

The Lifeboat Foundation has a bioshield project


DARPA (the defense advanced research projects agency) is the R&D arm of he US military for far-reaching future technology. What most people do not realize is how much revolutionary medical technology comes out of this agency’s military R&D programs. For those in need of background, you can read about the Army & DARPA’s future soldier Landwarrior program and its medtech offshoots as well as why DARPA does medical research and development that industry won’t. Fear of these future military technologies runs high with a push towards neural activation as a weapon, direct brain-computer interfaces, and drones. However, the new program has enormous potential for revolutionary medical progess as well.

It has been said technology is neutral, it is the application that is either good or evil. (It is worth a side-track to read a discussion on this concept)

The Areas of Focus for DARPA in 2007 and Forward Are:

  1. Chip-Scale Atomic Clock
  2. Global War on TerrorismUnmanned Air Vehicles
  3. Militarization of Space
  4. Supercomputer Systems
  5. Biological Warfare Defense
  6. Prosthetics
  7. Quantum Information Science
  8. Newton’s Laws for Biology
  9. Low-Cost Titanium
  10. Alternative Energy
  11. High Energy Liquid Laser Area Defense System

the potential for the destructive use of these technologies is obvious, for a a complete review of these projects and the beneficial medical applications of each visit