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Reconnissance Sampling and Decontamination Module
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Index to Reconn/Decon Webpages Plague |
Counter-Measures Against Plague
The Yersinia pestis Bacteria
Plague is caused by the bacteria, Yersinia pestis. The bacteria form stout rods, 0.5 - 0.8 microns in diameter and 1.5 - 2.0 microns long. (A micron is one thousandth of a millimeter.) The rods are pink rather than purple when stained with Gram's stain, and thus, are Gram-negative. When stained with the Wright/Giemsa stain, granules at the ends of the rods are colored purple as seen in the image above. The bipolar appearance resembles a closed safety pin as indicated in the sketch on the right. Plague: a Disease With a Long History of Devastation The first documented very large epidemic or pandemic of plague began in Egypt in AD 541. It swept through the Middle East and the rest of the known world during the next 4 years. In 1346 the plague pandemic known as the Black Death or the Great Pestilence ravaged the Middle East, killed more than 13 million in China and 20 to 30 million people in Europe or one third of the population there. The pandemic lasted 130 years. In 1855 the third pandemic began in China, spread to all inhabited continents, and killed more than 12 million in China and India alone. Large Reservoir in Rodents, Vector in Fleas
Spread of Plague in the U.S.
The map on the right shows that plague has spread through much of the Western United States, where it is endemic in the rodent population and occasionally affects humans.
Domestic Cats
Plague in Humans When a person is bitten by a plague-infected flea, a swollen area--a bubo--develops. This form of the disease is known as bubonic plague. In advanced stages, dry gangerene (dead tissue killed by the plague toxin) forms on extremities, the nose, and elsewhere creating the appearance called "The Black Death".
Plague Used as a Biological Warfare Weapon The program of the Japanese Army before and during the Second World War to develop plague into a weapon for biological warfare soon discovered that aerosols of plague droplets do not survive very long. However, plague-infected-fleas seek out hosts and are effective in transmitting the disease. Japanese clay bombs containing human fleas infected with plague killed hundreds of Chinese during the Second World War. Releasing thousands of plague-infected lab rats at the end of the war caused tens of thousands of Manchurian casualties in plague epidemics after the war ended. The U.S., the Soviet Union and a number of other nations have solved the problem of how to make "weaponized" plague that can be released as an aerosol. Plague is just one of the many ways that mankind can cause its own destruction. Counter-Measures Against a Bioterrorist Attack That Uses Plague The most effective counter-measure against a bioterrorist attack using plague as the agent is to prevent the attack from happening. In the aftermath of September 11, 2001, there is a vigorous effort to strengthen the defenses of the country. The change in public attitude has been dramatic. Vigilance is being exercised by the average citizen in a manner unknown several years ago. Release of a large quantity of plague as an aerosol with the intent to infect a large outdoor area and cause many casualties is an unlikely scenario. However, the threat deserves to be taken seriously in planning for national security. Precision Lift, Inc. developed the Reconn/Decon Module as a quick-response module for Civil Support Teams of the National Guard (or similar units in other branches of the Armed Forces.) In the immediate aftermath of an outdoor plague aerosol attack, there will be a need to determine the location and extent of the contaminated area. Where to quarantine and to whom to administer antibiotics are important aspects of managing the consequences of an attack. Tracking the Aerosol Cloud Pneumonic plague affects humans. It also affects mice and other small rodents. Mice can be used as to sample the extent of the contaminated zone. A two man sampling team with helicopter support can set out many hundreds of traps during one day and the next day collect the specimens and have them analyzed using the newly developed techniques for rapid determination of plague DNA and plague antibodies. A suggested sampling scheme is along series of concentric circles or circular arcs around the location of known victims. In contrast to a natural epidemic in which fleas infect their hosts, in the aftermath of an aerosol attack, the hosts will have the disease before the fleas. The well known snap traps for mice are small and easily transported in large numbers. A smaller number of the much larger and heavier live traps are included in the Biological Sampling Kit. Snap traps kill the mice and the fleas quickly leave as the body cools. Live traps sample both the mice and the fleas. Because plague is endemic in many areas and there are periodic severe outbreaks in the rodent population, some baseline data collected well beforehand will be very helpful in interpreting the results of a mouse survey done during a crisis. The baseline data can be collected during routine training exercises. Useful Links to Other Websites Introductory Discussions of Black Death and Yersinia pestis The Virtual Museum of Bacteria has a page on plague pandemics and one on Yersinia pestis. The text is designed for general (i.e. non-professional) audiences. The story of the oriental rat flea and Black Death in the Middle Ages is well illustrated on the Insecta Inspecta Website of Thornton Jr. High in Fremont, CA (with help from the Smithsonian Institution). The fleas are attracted to humans by the carbon dioxide that they exhale. The classic 14th Century book, The Decameron, by Boccaccio relates 10 stories a day for 10 days told by a group of young people escaping the plague near Florence, Italy. On-Line Medical References The online consensus statement on plague is available from the Center of Disease Control. It gives an authoritative summary of the disease for medical professionals, together with references to many articles in the medical literature. The chapter on biological warfare in the on-line textbook on dermatology has many illustrations of both the appearance of various symptoms and views through the microscope of the bacteria and viruses responsible for the diseases. The home page for plague at the Center for Disease Control opens to a series of short, factual, and readable pages. Endemic Presence of Plage in the Western U.S. The U.S. Army guide (Technical Guide #103) for the "Prevention and Control of Plague" has a detailed discussion of vectors and hosts for plague. Particular helpful are the lists of the 92 different species of mammmals that have been infected with plague and the 68 species of fleas found on these mammmals. Listing the host/vector pairs found at each of the many Army facilities in the West is a useful indicator of the manner in which the disease is endemic. This is a "hands on" manual with step-by-step instructions for studying plague. The H.B. Sherman Company has a large folding aluminum live-trap (3" x 3" x 9"). This trap has been extensively used in trapping mice for hantavirus studies in Montana and elsewhere and is part of the Biological Sampling Kit. The Center for Disease Control has a manual giving step-by-step procedures for trapping small mammals and collecting samples of blood and various organs. The manual can be downloaded in .pdf format for viewing with the Acrobat Reader.
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Role of the CST WMD Reconn-Decon Module Specs for Module Chemical Terrorism Chemical Response Kit Bio-Terrorism Bio-Sampling Kit Anthrax Tularemia DNA Studies Decon Shower Decon Solutions
Plague is one disease on a long list of diseases that were "weaponized" by Japan, the Soviet Union, the U.S., and other governments during the last century for use in biological warfare. The attacks in September and October of 2001 suddenly made the U.S. aware of its vulnerability to biological agents. General Aviation is now monitored by the Federal Aviation Administration. Cropdusters, such as the one shown on the right, receive especially strong scrutiny. Precision Lift, Inc.'s contribution to the Homeland Defense effort is its 
The brown rat or Norwegian rat, Rattus norvegicus, largely displaced the black rat from urban areas in Europe. This rat lives in burrows dug under buildings and trash. The human flea, Pulex irritans, is also an important vector in transmitting the disease from rats to humans.
Plague officially entered the U.S. in 1900 when a dead Chinaman was discovered in a hotel room adjacent to the Port of San Francisco. The disease spread quickly. In 1924-1925 Los Angeles had an epidemic of pneumonic plague, prompting major improvements in rat control and urban hygiene. Loss of rat habitat resulted in the disease moving from the cities to the countryside, and finding new hosts.
The major hosts for plague in the Western States currently are deer mice, ground squirrels, rock squirrels, and prairie dogs. The blacktail prairie dog is illustrated on the left and the California ground squirrel on the right.
Mice become infected with plague. Cats catch mice and in turn become infected. The cat owner is scratched or otherwise becomes infected from the cat. Since 1977 there have been 15 reported cases of people in the U.S. being infected with plague from domestic cats.
When a person inhales small airborne droplets containing plague bacteria, pneumonic plague soon develops in the lungs. The body tries to expell the fluids and mucus in the lungs by frequent coughing. The tiny droplets expelled during coughing bouts are very contagious, quickly infecting others. Thus the bacteria spreads rapidly from person to person.