Bacteriological warfare

2.1 CHARACTERISTICS OF MICRO-ORGANISMS
Micro-organisms are minute living organisms, usually microscopic (that is, too small to be seen by the unaided eye). When magnified 500 to 1000 times by the microscope, each micro-organism is found to be composed of a single cell or a group of associated cells, each of which is capable of carrying on all the functions of life, including growth and reproduction. Lacking a digestive tract, the micro-organism acquires food in soluble form through the moist membrane which surrounds the cell contents. Not possessing organs of sight, it does not differentiate light and darkness by the visual method. Having no heat regulating system it assumes the temperature of its surroundings. Micro-organisms are so small that the unit applied in their measurement is the micro, which is equivalent to 0.001 millimetre or approximately 1/25,000 of an inch. Micro-organisms capable of producing disease are called pathogens. Most of the pathogens are parasites, since they five in, on, or with some other living host at whose expense they obtain food and shelter. Organisms which multiply in dead rather than in living matter are called saprophytes. While most of these are harmless, some produce poisonous products which cause disease. Examples of some of these harmful saprophytes are the bacteria which cause tetanus, producing their poison in macerated, devitalised tissue, and those which cause botulism manufacturing their toxin in food outside of the body. Most micro-organisms are non-pathogenic, and many are beneficial to animal and plant fife. From the secretions of certain micro-organisms some of the most powerful antibiotics, such as chloromycetin, penicillin, and streptomycin, have been obtained.

Micro-organisms are important in the preparation of dairy products and in the fermentation industry (for example, rising of bread and production of vinegar and alcoholic beverages). Sod fertility is largely dependent upon their activity in decomposing dead matter and releasing the elements needed for the growth of plants. Micro-organisms are universally distributed in the air, water, and soil. Soil organisms are found in all surfaces exposed to dirt and dust, and every cubic foot of topsoil provides the natural home for billions of them. The skin, hair, nose, mouth, and digestive tract of man and animals harbour a considerable variety of micro-organisms in large numbers. However, the pathogenic, or disease-producing organisms of man, animals, and plants, with very few exceptions, usually do not live long or grow when in the absence of a suitable host, and favourable environmental conditions are necessary for survival.


2.2 GROWTH AND SURVIVAL
Numerous factors influence the growth of micro-organisms, which are more dependent on a delicately adjusted environment than are higher forms of life. Some of their requirements are:

• MOISTURE
  A plentiful supply of water is essential, as this amounts to about nine-tenths of the cellular substance, and is the vehicle by means of which soluble food is made available by diffusion through the cell wall. It also is required in the immediate surroundings to prevent drying of the organism; even a small decrease may interfere with normal functions and cause death. However, it is possible to keep even quite delicate organism alive by lyophilization, which is a combined process of quick freezing and drying at very low temperatures.
  
  
• FOOD
  Food is required to supply building material and energy. Micro-organisms in general can utilise a wide variety of substances, including proteins, sugars, minerals, salts, and vitamins, but the requirements of different species are not the same, either in the kinds of food or in their proportions. As mentioned previously, the parasites normally feed on living plants or animals but, under favourable conditions, some will grow in foodstuffs or artificial media- the saprophytes require dead or decaying organic matter. The viruses and rickettsiae will grow only in the presence of living host cells; thus they are obligate parasites.
  
  
• OXYGEN
  As with higher forms of fife, all micro-organisms require oxygen to live, but they may differ markedly in respect to the source from which they obtain it. Those which grow only in the presence of free oxygen are called obligate aerobes, while those which grow only in the absence of free oxygen are termed obligate anaerobes and obtain their oxygen in the combined form from various chemical compounds. Lying between these two extremes are the facultative aerobes, which are fundamentally anaerobes but can grow in the presence of free oxygen, and the facultative anaerobes, which are essentially aerobes but can grow in the absence of free oxygen. Most of the pathogenic micro-organisms are facultative because they may obtain their oxygen in either form. In either case, the supply of oxygen is essential to provide energy and to aid in the formation of new cellular material.
  
  
• TEMPERATURE
  Temperature is an important factor, each species of organism developing most abundantly at a particular or optimum temperature range. Pathogens of warm-blooded animals develop best in the narrow temperature ranges common to these animals. At variations either below or above this range, the organism functions progressively less effectively until temperatures are reached at which growth no longer occurs. High temperatures are fatal, but survival often occurs at low temperatures. Climatic conditions might be decisive factors in determining whether certain micro-organisms could be used in desert or arctic warfare.
  
  
• LIGHT
  Most micro-organisms do not require light for growth. They are destroyed by prolonged direct exposure to ultraviolet rays from the sun or from artificial sources. Consequently growth occurs best in an environment protected from direct sunlight.
  
  
• REACTION OF MEDIUM
  In general most micro-organisms associated with animal life grow best in neutral or slightly alkaline surroundings. Those associated with plant life often prefer a slightly acid environment. Growth is inhibited by highly acid or highly alkaline surroundings.
  
  
• TIME
  When micro-organisms are placed in a new environment, there is a period of adjustment or lag phase in which the number of cells does not increase appreciably. If all essential factors are favourable and there is no opposition from the host, an insignificant number organisms may develop within a few hours, or at most, days, into numbers almost beyond comprehension.
  
  
• ENCAPSULATION
  The formation of capsules, a process known as encapsulation, is a property of many bacteria which may favour their survival. The capsule is also associated with variety of pathogenic bacteria. For example, pneumococci that are encapsulated are highly virulent whereas when they have no capsule they are relatively avirulent. Anthrax bacilli are almost always found to be encapsulated when observed in preparations made from animal tissues. The capsule appears to function as a bacterial defence against the activity of phagocytic cells of the body. The capsule apparently originates from the outer layer of the cell membrane and consists of a thick, colorless (translucent) outer wall of gelatinous (protein), gummy (polysaccharide), or fatty material. There is good reason to believe that capsule formation may be stimulated by unfavourable environmental conditions such as the resistance of an infected host.
  
  
• SPORULATION
  Another protective mechanism favourable to survival among bacteria is sporulation, which leads to the formation of heavy walled bodies called spores. Sporulation is not necessarily a response to unfavourable conditions, since spores are often formed early in the life of a culture while conditions are wholly favourable to continued vegetative activity. Bacterial spores are more resistant to injurious or unfavourable influences (such as starvation, high and low temperatures, germicidal chemicals, drying, and oxidation) than the growing or vegetative forms. When the spore has matured, the surrounding vegetative form disintegrates. The resistance spores thus formed may remain dormant for years without food or water, and under extreme range of temperatures, and again develop into an actively growing vegetative cell when conditions become favourable. Spore formation is not a method of multiplication in the bacteria, for each vegetative cell forms only a single spore and each spore germinates into a single vegetative cell. Therefore, it is considered a means for the perpetuation of the organism. Since the rate of growth of certain species is accelerated after spore formation, the .process may serve to rejuvenate the activities of the bacterial cell. In higher fungi, such as molds and mushrooms, spore formation, either sexual or asexual is the normal method of reproduction.

2.3 REPRODUCTION May be sexual or asexual, depending on the micro-organism, but the asexual process is the more common.

• ASEXUAL
  Asexual reproduction may occur by by fission, by budding, or sporulation. In binary fission, the cell divides into two equal and identical parts, each of which develops into a new organism. In budding, a small portion of the parent cell is pinched off and develops into a new, actively growing individual. In fungal sporulation special cells are set aside for reproduction. The bacteria reproduce by asexual binary fission; the yeasts, which belong to the fungi, reproduce sometimes by asexual by fission but usually by budding or by sexual spore formation. The higher fungi usually reproduce by sporulation. Protozoa may reproduce by fission, but sexual reproduction is common in certain species.
  
  
• SEXUAL
  Sexual methods of reproduction are often encountered among micro-organisms. These involve copulation of two cells with interchange of cellular contents, usually resulting in the formation of spores of various types. Sexual reproduction is known to occur among the fungi and protozoa, although it is often difficult to identify the cells as male or female.

2.4 IDENTIFICATION
The methods involved in the identification of most micro-organisms are difficult and time-consuming and usually are dependent upon obtaining living organisms. As organisms exhibit preference for environments in which they will grow (that is, the type of material required for their survival), information as to the source of the organism is of value in establishing its identity. Usually, such information will not be immediately available under the conditions of biological warfare. Laboratory procedures are used to establish or confirm the identity of a micro-organism. A few of these methods are described below.

• SAMPLING
  Rapid identification of a micro-organism used as a BW agent is dependent upon sampling procedures capable of obtaining a large number of viable organisms relatively free from interfering materials or other organisms. Methods of collecting suspected material vary with its nature and source, that is, living or dead tissue, body secretions, sod, air, water, surfaces of all kinds, and with methods of its release, such as aerosols from various spraying devices or bombs. If the agent is released as an aerosol (cloud or spray), every effort should be made to obtain an air sample as near the point of release as possible. The number as well as the viability of the organisms released in an aerosol will decrease progressively with the passage of time and with increasing distance from the point of release outward. Also the original aerosol is relatively uncontaminated, since there are few naturally occurring organisms in the air. Samples of vegetation, water, soil, and other materials on which the agent has fallen may be of value in aiding or helping confirm the identity of the agent even though the samples contain interfering contamination and yield a smaller number of organisms than are found in the original aerosol. Such samples should be taken if conditions or other factors make it impossible to obtain air samples of the original aerosol or if there is evidence that a poorly representative sample might have been taken. These samples should be taken as soon after release and as near the point of release as possible. Air samples may be obtained by drawing the air through a simple coffee filter, or bubblers, by bringing the air in contact with the surface of nutrient media, or by using special filtering devices. Vegetation, water, and soil samples are obtained by placing portions of each in sterile containers. Samples from other contaminated surfaces may be obtained by rubbing the surface with a sterile cotton swab and placed in a sterile capped container. The samples are then sent, by the fastest method available, to the nearest designated laboratory for identification.
  
  
• MICROSCOPIC EXAMINATION
  Micro-organisms (except viruses and rickettsiae) in smears or suspensions of suspected material may be examined and counted under a microscope for identification purposes. Such examinations may be aided by staining the micro-organisms with dyes, which bring into sharper detail the shape, relative size, and presence of spores, capsules, or flagella of certain micro-organisms which otherwise might not be noted. A very important staining procedure is the Gram method. In this process the specimens are first stained, then exposed to a decolonizing fluid, and subsequently counter stained. Organisms retaining the primary stain are called gram positive, and those stained by the secondary stain are grain-negative.
  
  
• CULTURE
  Micro-organisms may be cultivated by placing samples of them in sterile containers holding solid or liquid nutrient media and incubating them at temperatures suitable for growth for specific lengths of time. Organisms multiplying on solid media form visible masses or colonies whose surface appearance, shape, and color help in their identification. In liquid media, identification of the micro-organism is aided by determining what kinds of food are required for its growth and what substances it produces.
  
  
• TESTS
  Micro-organisms may be identified biochemically by cultivation of them in certain media, observation of the by-products or their growth, and determination of what materials they consume. By the addition of certain chemical compounds to the media, it is possible also to differentiate between different kinds of micro-organisms by unequally influencing their growth. Biological tests are also practicable for identifying many micro-organisms. Suitable animals are injected with the suspected organism, and clinical or post-mortem observations of pathological changes are made. When a certain kind of organism is under suspicion, it may be inoculated into animals which have been immunised against it and into an equal number of non-immunised animals; if the suspicion is correct, the non-immunised animals will develop the disease, while the immunised animals will not. A third method of identification is by serological testing. This is based upon the occurrence in all living cells of specific protein substances known as antigens which, when introduced into the blood or tissue of a foreign animal body, induce the formation of specifically reacting antagonistic substances known as antibodies. Since antibodies usually appear in the blood serum, which is then used in testing for specific antigens, these antigens-antibody reactions are known as serological reactions. It is possible with serological reactions to distinguish between different but closely related organisms, thus aiding in the diagnosing of an infectious disease.

2.5 INHIBITION AND DESTRUCTION
The term "inhibition" is used to indicate arrest in growth or multiplication (reproduction), while destruction refers to death; sterilisation is synonymous with destruction. These phenomena may be brought about by physical, chemical, or biological means.

• TEMPERATURE
  High temperatures are effective in destroying micro-organisms. Higher temperatures or longer exposures are required when dry heat is used than when moist heat is used. Direct exposure to flame and to steam under pressure are reliable for sterilising materials which are not harmed by these methods. Boiling water or flowing steam are effective when resistant species or spores are absent. Some delicate organisms, however, do not survive even small temperature fluctuations of their environment. On the other hand, rapid lowering of the temperature to sub-freezing accompanied by quick-drying tends to preserve the life of many micro-organisms, and they survive in a state of suspended animation.
  
  
• DESICCATION
  Desiccation, or drying, is one of the oldest measures used to prevent spoilage of food by micro-organisms, examples being the production of jerked beef, prunes, powdered milk and eggs, and other dehydrated foods. In the absence of moisture, food cannot diffuse through the cell membrane, and growth of the organism ceases. Vegetative organisms are particularly susceptible to drying, but spores are practically unharmed. Drying may reduce the number of living organisms but cannot be relied upon for their complete destruction.
  
  
• STARVATION
  Growth can be inhibited and sometimes and sometimes death induced when essential food materials are removed or rendered unavailable. All micro-organisms require oxygen, carbon, nitrogen, and hydrogen in some form; if any one of these elements is limited or converted to an unusable form, the micro-organism cannot develop and may eventually die. Varying amounts of other materials too numerous to name in this text also are essential, depending on the kind of organism involved. Spores, as opposed to vegetative forms, can remain dormant for long periods without food; hence spores may not be killed by starvation, but their germination may be prevented.
  
  
• LIGHT
  Ultraviolet rays from the sun or artificial sources quickly destroy exposed micro-organisms, but these rays have low penetrating powers and may be ineffective against microbes protected by thin liquid or dust films, rough surfaces, or opaque liquids.
  
  
• FILTRATION
  Micro-organisms can be removed from air and liquids by various filtering devices. The efficiency of filtering processes depends not only on the kind of filter used but also upon such factors as particle size and number of organisms present, electrostatic charge, and rapidity of filtration. The larger organisms may be removed by filtration through asbestos pads, collodion, or other specially prepared membranes, filter paper, or unglazed porcelain, the pore sizes of which are too small to permit passage of the micro-organisms. Some micro-organisms, such as viruses, are so small that they cannot be removed by or bacterial filters but require special filtration devices. Gases such as air, containing dust like suspensions of micro-organisms, can be effectively filtered through thick layers of cotton batting or other materials.
  
  
• OSMOSIS
  The diffusion of a liquid through a semipermeable membrane that separates two miscible solutions is known as osmosis. Although the diffusion may proceed in both directions, the flow of solvent is greater from the more dilute to the more concentrated solution. This diffusion tends to equalise the concentration of the two solutions. Osmotic pressure is the increased pressure which develops in the more highly concentrated solution. Living cells, including micro-organism, all have semipermeable cell membranes; hence when they are placed in high sugar or salt concentrations, the osmotic process removes water from them, resulting in inhibition of growth or destruction. Common applications of this principle are the use of high concentrations of sugar to preserve foods, such as jams and jellies, and the soaking of meat in brine. However, these measures are not effective for destroying spores.

2.6 GENERAL, CHEMICAL
Many chemical compounds are used to destroy or inhibit the growth of micro-organisms. Disinfectants are materials such as germicides and bactericides, which destroy pathogenic micro-organisms. Antiseptics are substances which inhibit the growth and development of micro-organisms, but do not necessarily destroy them. Some chemicals are powerful disinfectants, while others are only inhibitors. Among the common disinfectant and antiseptic preparations are mercuric chloride, silver nitrate, tincture of iodine, chlorine, phenol, cresol, formaldehyde, hydrogen peroxide, alcohol, hypochlorites, and acids or alkalis. The vapors of propylene glycol, triethylene glycol and ethylene oxide are also effective disinfectants and decontaminate. Proper concentration, temperature, and length of exposure are critical factors in the employment of all these materials.

• CHEMOTHERAPEUTIC AGENTS
  These are chemical compounds, used in the treatment of disease, which affect the causative micro-organism unfavourably without markedly injuring the patient. They may destroy the pathogen, inhibit its growth, or render it more susceptible to the defence mechanisms of the body. Among these substances are arsphenamine, quinine, and the sulfonamides-sulfanilamide, sulfadiazine, and sulfa pyridine-and others.

2.7 BIOLOGICAL

• ANTIBIOTICS
  Are substances (chemical compounds) produced by living cells and are selectively antagonistic to other living organisms. (They have the capacity to inhibit the growth of and to destroy various micro-organisms.) They are usually obtained from micro-organisms, such as bacteria, yeasts, and molds, and sometimes from higher plants. Some antibiotics, such as chloromycetin, originally obtained from a micro-organism have been synthesised. No one antibiotic is inhibitory to all micro-organisms, but each has a more or less specific inhibitory or growth-preventing action on particular species. Some have proved valuable in the treatment of diseases not responsive to chemotherapeutic drugs, vaccines, or antiserums. Prominent antibiotics including penicillin, streptomycin, chloromycetin, and terramycin.
  
  
• BACTERIOPHAGES
  Are viruses which are parasitic to certain bacteria and may destroy them. Like other viruses, bacteriophages multiply only in the presence of living cells. They are widely distributed in nature and are commonly present in the intestines of man and animals, especially those recovering from a bacterial disease. There are various strains or races of bacteriophage, each being specific for certain types or groups of bacteria, but many bacteria, including some of the more pathogenic, have no known bacteriophage. A very small amount of bacteriophage, when added to an actively growing susceptible bacterial culture, will cause swelling, death, and disintegration of the bacterial cells within a few hours.

2.8 INFECTION AND IMMUNITY, GENERAL
Infection occurs when pathogenic micro-organisms invade the tissue, multiply, and produce injury or death. It represents a conflict between the invader and the living object of attack, in which the host strives to resist the invasion and repel the invading organisms. If they are repelled, the defender suffers no ill effects; if not, infection occurs. Factors which influence the outcome of the struggle are the portals of entry, the virulence and number of organisms, and the defensive powers of the defender-man, animal, or plant. Micro-organisms range from those which produce disease (pathogens) to those which do not produce disease (non-pathogens). Under some circumstances, organisms that are considered non-pathogenic may produce infections; examples are the normal bacteria of the gastrointestinal tract which can produce disease like peritonitis, colitis, and urinary tract infections. Infections may or may not be transmissible to other individuals. A contagious disease is an infection which spreads readily from one individual to another by direct or indirect contact. Examples are Typhoid fever, Plague, and Cholera.

• THE PRINCIPAL AGENTS OF GERM WARFARE
  The chief requirement of an effective biological weapon is that the organism be highly infectious by the respiratory route, thus permitting effective airborne dispersal. Of these Plague (Yersinia pestis) is the most likely candidate a terrorist would use against the North American continent. This organism is highly infectious and causes a serious incapacitating disease, that is most often fatal. The organism can infect either the respiratory or oral route, and can be readily cultivated in the laboratory. All contagious diseases are infectious; however, infectious diseases are not necessarily contagious (tetanus, brucellosis, tularaemia, malaria).

2.9 FACTORS OF INFECTION

• VIRULENCE
  Virulence refers to the relative infectiousness of an organism or its ability to overcome the defences of the host. Pathogens range in virulence from those producing mild and temporary disturbances to those causing incapacitation or death. Virulence of certain organisms can be increased by repeated passage from animal to animal. In general, virulence is dependent on two factors-invasiveness and toxicity.
  
  
• INVASIVENESS
  Is the ability of a micro-organism to enter the body and spread through the tissue. It is the predominant factor in the virulence of some micro-organisms, such as those causing tularaemia and blood poisoning.
  
  
• INFECTIVE DOSE
  The infective dose denotes the number of organisms necessary to produce infection in an exposed individual. It is an extremely variable factor, depending on the micro-organism involved and the species or individual attacked; in some cases, relatively few organisms can produce an infection, while in others large numbers may be required.
  
  
• INCUBATION PERIOD
  When micro-organisms have been introduced into the host in sufficient amounts to produce disease, an interval of time, known as the incubation period, elapses before symptoms of disease appear. During this time the organisms establish themselves firmly and increase in numbers large enough to cause disease. The incubation period may vary from a few hours to a few weeks, depending on the kind of pathogen and, during this interval there may be no sign of disease. At the end of the period, symptoms may appear either gradually or suddenly, and the full developed disease will become evident. A similar lapse of time occurs between the introduction of non-living toxins and the appearance of disease symptoms; this may more aptly be termed a latent, rather than an incubation, period.
  
  
• ROUTES OF INFECTION
  The principal portals of entry for micro-organisms into man and animals are through abrasions of the skin, through the mucous membranes of the respiratory, gastrointestinal, and genitourinary tracts, and through the eyes. However, it should be recognised that the unbroken skin and mucous membranes are natural defence barriers which aid in preventing an invasion by pathogenic organisms. Certain organisms require specific routes to infect, while others can invade by several routes. Most respiratory diseases are contracted be the inhalation of droplets of contaminated moisture or dusts. Intestinal infections are produced by the ingestion of contaminated food or drink. Some organisms invade by penetration of the skin through hair follicles, sweat gland ducts, or abrasions; other organisms must enter through wounds in order to establish themselves. Tetanus spores, for example, may be swallowed with impunity by man; but if they are introduced into a lacerated wound - tetanus may develop.
  
  
• SYMPTOMS OF INFECTION
  In the early stages of disease, a few general symptoms usually appear which indicate that infection has been established. These are fever, malaise, and inflammation.
  
  
• FEVER
  Warm-blooded animals, including man, normally maintain their body temperatures within quite narrow limits. The occurrence of an infection usually is accomplished by an abnormal rise in temperature, which is called fever. The degree of fever varies in different diseases, but may serve as a rough guide to the severity of the infection; however, the rise in temperature is a protective mechanism, unless it gets so high that it is harmful to the patient. As a rule, the individual with fever feels quite warm and his skin is likely to be flushed, but the onset of fever may be preceded by chill which causes him to shiver, sometimes violently. The chill does not necessarily indicate a drop in body temperature, even though there is a cooling sensation of the skin; the temperature of the interior of the body may be abnormally high. Fever, whether preceded by a chill or not, is usually one of the earliest symptoms of infection and is indicative of illness.
  
  
• MALAISE
  This is another early set of symptoms of infection in which there is a vague feeling of body discomfort, weakness, and exhaustion. It may be accompanied by nausea, dizziness, loss of appetite, and generalised aches; pains in the back, arms, legs, and head may be present. These symptoms may increase in severity as the disease develops or may be over-shadowed by other specific symptoms.
  
  
• INFLAMMATION
  Inflammation is a reaction of certain body tissues to injury and is characterised by pain, heat, redness, and swelling. Certain kinds of infection are indicated by inflammation of the skin, mucous membranes, or glands, as the body defences are mobilised to combat the invader and seal off the infection. Some infections are accompanied by a characteristic eruption or rash of the skin, by means of which it is often possible to make an early diagnosis of the particular type of infection that has occurred.

2.10 RESISTANCE TO INFECTION
The ability of the body to fight off or overcome an infection is known as resistance. The first fine of defence is provided by the skin and mucous membranes of the gastrointestinal, respiratory, and genitourinary tracts, and their secretions. These help prevent entrance of micro-organisms into deeper tissues, which have little ability to ward off invasion. The second fine of defence, of which the lymphatic system is a part, is a cellular one. Specific migrating cells of the body attack and destroy the invading organisms. The third line of defence is presented by the blood, which has neutralising bodies, and the liver and spleen, to which it carries organisms and toxins to be destroyed or inactivated.

• THE SKIN AND MUCOUS MEMBRANES
  The unbroken skin and mucous membranes act as mechanical barriers and are generally impervious to particulate material of bacterial size, some of which may, however, enter the skin through hair follicles and sweat gland ducts. Clean skin is also actively bactericidal to many pathogenic micro-organisms. Sweat acts as a bactericide and also aids in flushing away the germs. The mucous membrane, or mucosa, lines the surface of the canals and cavities of the body which communicate with the exterior, such as the alimentary canal and its connections, the respiratory tract and its branches, and the genitourinary tract. The mucosa produces a viscid watery secretion, known as mucus, which forms a protective covering and entangles invading micro-organisms. The constant movement, or peristalsis, of the gastrointestinal tract tends to trap micro-organisms in shreds of mucus and thus passes the organism into the lower bowel and out of the body.
  Micro-organisms are also entangled by the mucus of the nasal passages and trachea, or windpipe, and swept back to the mouth by coughing or by the action of cilia, which are small hairlike projections lining these surfaces. The mucus of the genitourinary tract acts in a similar manner. Other secretions, such as the acid juices of the stomach, the alkaline ones of the intestines, and the vaginal secretions, either inhibit or destroy micro-organisms, and the saliva and tears protect the body by a combination of lyasome and mechanical flushing.
  
  
• CELLULAR DEFENCE
  Should micro-organisms succeed in gaining entrance into deeper tissues, they are attacked-by cells known as phagocytes, which appear at the site of invasion within a few minutes and have the ability to ingest and destroy foreign bodies in the blood and other tissues. If the infective agents overwhelm the phagocytes and penetrate more deeply, they may enter the lymph channels and be carried to the lymph nodes where they are engulfed by larger phagocytes. The swelling and tenderness of the lymph nodes are symptoms of this struggle.
  
  
• BLOOD DEFENCE
  In addition to the white blood cells, or leukocytes, which are wandering phagocytes, the blood also contains substances called antibodies. These are immune bodies manufactured by the body in response to the introduction of antigens, foreign protein like substances, into the tissues. Vaccines are typical antigens which, when injected into the body, cause antibodies to be formed. Micro-organisms and their products, such as toxins, are protein in nature; hence they are antigens. Each antibody is specifically antagonistic to the antigen which stimulated its production and combines with the antigen to neutralise or destroy it. Many kinds of antibodies are the basis of the active immunity which may be induced naturally or artificially in the body to provide resistance against invading micro-organisms or their poisonous products. Should the invading micro-organisms overcome the cellular and blood defences, they are carried into the blood stream and attacked by the large white cells or macrophages in the liver, spleen, and bone marrow, where the blood flow is slower than in other parts of the body, allowing more time and greater opportunity for the macrophages to engulf them.

2.11 IMMUNITY, GENERAL
The ability of the living individual to resist or overcome infection or injury by a pathogenic agent is known as immunity. Relative resistance to infection is dependent upon all the protective barriers, including the skin, mucous membranes, tissue cells, and blood. Resistance due to the presence of certain antibodies in the tissue is the primary factor in determining an individual's immunity. Immunity may be classified into several types.

• NATURAL IMMUNITY
  Certain species of animals, certain races of people, and certain individuals of a given race appear to be born with a resistance to certain infections. Examples of natural immunity are the resistance of man to foot-and-mouth disease, the resistance of dogs to anthrax, and the relative resistance of the Negro race to yellow fever.
  
  
• ACQUIRED IMMUNITY
  This type of immunity may be either naturally or artificially acquired and may be active or passive.
  
  
• NATURALLY ACQUIRED PASSIVE IMMUNITY (congenital)
  Infants possess immunity to certain infections in the first months of life due to antibodies acquired from the mother. These antibodies soon disappear, and the conferred immunity is then lost. An example of this type of immunity is the resistance of infants to diphtheria during the first year of life.
  
  
• NATURALLY ACQUIRED ACTIVE IMMUNITY
  This type of immunity is generally the longest lasting of all immunities. It may be the result of recovery from an attack of an infectious diseases such as typhoid, diphtheria, or tularaemia (rabbit fever); or may be attributed to an earlier, mild, unrecognised infection or to repeated contact with the disease producing organism in insufficient quantities to produce disease.
  
  
• ARTIFICIALLY ACQUIRED ACTIVE IMMUNITY
  This type of immunity is produced through injection of vaccines of attenuated or dead organisms or injection of toxoids (inactivated toxins) to which the body reacts by forming specific antibodies. Duration of immunity thus acquired varies considerably, depending upon the specific disease and the type of vaccine or toxoid used. Examples of effective vaccines are those of smallpox and typhoid. An example of an effective toxoid is that of diphtheria.
  
  
• ARTIFICIALLY ACQUIRED PASSIVE IMMUNITY
  This type of immunity is obtained by the injection into the body of antibodies (immune serum) actively produced in another individual or animal in response to either natural infection or injections of specific vaccines. An example of this is the immunity conferred by an injection of tetanus antitoxin. This immunity is relatively short-lived.
  
  
• TREATMENT PROBLEMS
  Certain factors may arise in a terrorism germ attack that will complicate treatment of casualties. These factors include the probable employment of overwhelming numbers of pathogenic organisms in an attack, AND the unavailability of sufficient quantities of antibiotic, and shortages of medical supplies, personnel and facilities, in the event of an overwhelming number of casualties occurring at one time. Other complicating factors might include fatigue, malnutrition, and climate conditions which would accelerate the course and severity of the resulting disease.
  
  

2.12 VECTORS OF DISEASE
In general, the term "vector" refers to the arthropods, including such as mosquitoes, flies, fleas, and lice, and a few acarids, such as mites and ticks. In some cases higher animals such as rats, cats, dogs and even man himself are considered vectors.

• FLIES
  The true flies have only two wings, but the word 'fly' is often applied in compound names of other insects, such as mayfly, saw fly, and stonefly. Most of the many varieties of flies have sucking mouth parts, but those few which have mouth structures capable of piercing the skin of man or animals include the most important disease vectors. The sucking flies can, however, introduce infection through previously injured body surfaces and are capable of mechanically transferring pathogens to exposed surfaces and food. Typhoid fever, bacillary and amoebic dysentery, and cholera are examples of disease which may be spread mechanically by non-biting flies. Yaws, a highly infectious and contagious non-venereal Spirochaetal disease resembling syphilis, may be acquired through a cut or abrasion of the skin, either directly by contact with discharges from lesions or indirectly through the agency of non-biting flies. The non-biting flies, which include the common housefly, are often termed "filth flies." It should be emphasised that they may easily carry pathogenic micro-organisms from excrement, sputum, open sores, or putrefying matter to food, milk, and healthy mucous membranes. Tularaemia (rabbit fever), a bacterial disease of wild animals and man sometimes transmitted by the horsefly and wood tick.
  
  
• FLEAS
  Fleas are small, wingless, insect parasites of the skin of mammals and birds. Their bodies are flattened laterally, and they have mouth parts for piercing the skin. While different species show preferences for certain hosts, when hungry they will attack any warm-blooded animal, which greatly increases their potential to transmit disease to man. The common rat flea is the vector of marine typhus, a rickettsial disease of rats and mice, and occasionally bites and infects man with the disease; it is the chief vector of PLAGUE from rats and other rodents to man and among rats and mice. Other fleas are known vectors of PLAGUE in the western United States. Fleas can also transmit HIV (AIDS).
  
  
• LICE
  The lice are sucking, dorso-ventrally flattened, wingless insects, parasitic on the skin of mammals and birds. The body louse (and probably the head louse) is the vector of rickettsial diseases, epidemic typhus, trench fever, PLAGUE and HIV (AIDS).

3.1 PURPOSE
The purpose of using BW agents is to produce widespread injury or death in man. Under the term "living organisms" are included not only micro-organisms, but also higher forms of animal life which injury by acting as vectors of disease. The micro-organisms which could be used as BW agents are "FEW", compared with the total number known, but they include the most promising candidates. Any pathogens that could cause diseases having high mortality or morbidity rates might be useful in Biological warfare. The toxins are comparatively scarce in number; while they include some of the most poisonous substances known, practical problems exist which will have to be solved before their potential usefulness can be ascertained. In the former Soviet Union, after an enormous out lay of capital, came up with an effective Biotoxin weapon. This weapon was known by the term "yellow rain", the process involves the solvent extraction of a toxin produced by Staphylococci aureus which causes Disseminated Intra vascular Coagulation. This toxin was impregnated upon wheat flower giving it a yellow color. This material had to be maintained in an oxygen free environment prior to being used, as oxygen would deactivate the toxin within 48 hours. The toxin was delivered to target area in two ways, one way was to spray it from aircraft over a target area. The toxin settled to the ground in a yellow mist, thus the term "yellow rain"; the lethal dose was very small. Once inhaled, the blood started to coagulate from the head and lungs. Death resulted with in minutes and as the toxin was deactivated with in forty eight hours, soldiers could quickly and safely enter the area. This toxin weapon was also mounted onto RPGs for selected targets. Another Biotoxin developed by the former Soviet Union was the STAR. This was pure crystalline Botulism toxin and is the most powerful poison known. It was believed to be a sabotage weapon, to be directed against municipal water supplies. It is unknown how far this project went, or if it was even completed. If indeed this project was completed and a terrorist group obtained this weapon, and introduced it into a city's water supply the death toll would be enormous. The only defence against this toxin is to boil the water before drinking as botulism toxin is heat liable and only five minutes of boiling will deactivate it.

3.2 PROPERTIES PECULIAR TO BW AGENTS
Most of the BW agents, particularly the pathogenic micro-organisms and toxins, have certain properties not possessed in general by other weapons. They have a delayed action it that a lag or incubation period, often of days, must elapse between the time the victim is exposed to an infectious agent and the time when he comes down with the disease. Identification of microbial agents is difficult and slow as their presence cannot be detected by the unaided senses; it takes hours and usually days for microbial agents to develop in artificial media. However recently developed immunological procedures such as precipitant, agglutination, immune diffusion, complement fixation, enzyme immune assay (EIA) make for rapid identification of possible BW agents. The micro-organisms are living agents in contrast to other agents of warfare. Under favourable conditions pathogenic micro-organisms can reproduce and multiply in the host, so that small numbers of pathogens may in time constitute a grave risk to health or perhaps to fife. Some contagious pathogens spread from individual to individual and cause epidemics. Most are also quite selective, attacking only certain species of animals or plants. While a given weight of biological agent theoretically may be many times more dangerous than an equal amount of the most effective chemical agent, from a practical standpoint its activity is strictly limited by its ability to survive and maintain its virulence under exposure to air, light, cold, dryness and dissemination methods and its ability to overcome the resistance of the target host. Finally, biological agents lend themselves well to covert use, because the small amounts of material needed are easily concealed, transported, and used in sabotage operations. Because of the relatively small amounts required, their cost should be much less than that of other agents or weapons.

3.3 EPIDEMIC SPREAD
A regional outbreak of a contagious disease which attacks many individuals and spreads rapidly is called an epidemic. In each condition there is an unseal increase in the number of cases of the disease in a limited time among a limited population. In nature, the spread of disease occurs from direct contact between individuals, from contact with or ingestion of excreta and contaminated food, from exposure to dusts and mists of infected material (aerosols), and through transmission by animal or insect vectors. Following large-scale dissemination of a biological agent, an initial outbreak of disease of epidemic proportions might occur. This might or might not be followed by a secondary or epidemic spread of the disease, depending upon its relative contagiousness, the presence or absence of favourable environmental conditions, and other factors. Since epidemics among the human population can be prevented or controlled by sanitation, immunisation. quarantine, and treatment, rapidly spreading epidemics are not considered to be likely aftermath's of biological attacks in civilised countries as long as these controlling factors remain at a high level of efficiency. Epizootic among animals have more dangerous possibilities than do epidemics among persons because of the herding and feeding habits of animals; their control or elimination requires extensive use of costly diagnostic and immunological procedures, quarantine where possible, and often the destruction of large numbers of infected animals. Effective measures of preventing of controlling plant epiphytotics and pest infestations are even more deficient and possibly, because of the tremendous amounts of manpower and materials required, the vectors involved, and the areas to be covered.

8.1 YOU MUST KNOW THE SCORE
This book is for you, the North American resident. Its purpose is to help you perform your job under BW conditions and to live to tell about it. The material presented in this manual is applicable to both germ and biotoxin warfare. When any poison gets into your body, it can cause sickness or death. Likewise, when biotoxin, or biological attacks occur, some casualties are certain.
Casualties are people put out of action, sick, wounded, missing, or killed. Biological agents cause casualties just as bullets and high explosives do. However, the number of casualties will depend on the knowledge of the North American citizen. Learn now what you can do to protect yourself and to help maintain the efficiency of your community. The skill of you, the individual North American, in protecting yourself will help determine the success of your community. Users of this book are encouraged to submit recommended changes or comments for its improvement. Comments should be keyed to the specific page, paragraph, and fine of the text in which change is recommended. Reasons should be provided for each comment to insure understanding and complete evaluation. Comments should be forwarded direct to my attention.

8.2 WHY THIS BOOK WAS WRITTEN
By studying this book you will learn basic facts that you must know in order to survive during a biological attack and maintain your job. It will answer most of your questions about survival under Biological Warfare conditions.

8.3 HOW TO GET THE MOST FROM THIS BOOK
As you read and study this book, ask yourself the following questions:

1. What are Biological operations?
2. How can biological agents injury or kill me?
3. How may I be attacked?
4. How can I protect myself against biological agents?
5. What can I do to help in minimising the number of casualties in my community?

In this book are the facts which answer these questions for you. Remember them! They can save your life!

8.4 WHY BIOLOGICAL WARFARE MUST BE TAKEN SERIOUSLY

• GENERAL
  The purpose of biological warfare is to produce casualties in man and animals and to cause damage to plants and material.
  
  
• BIOLOGICAL OPERATIONS
  The effects of harmful micro-organisms (germs) are well known to you. You have probably experienced the effects of disease such as colds, dysentery, measles, mumps, and chickenpox. Such diseases are caused by certain types of harmful micro-organisms which get into your body and multiply, thus producing infection.

Micro-organisms are living organisms that are so small they can be seen only through a microscope. Of the thousands of them in the world around us, the vast majority are harmless or actually beneficial to man. Only a few of the disease-producing micro-organisms are harmful enough to be considered for employment as biological agents. A biological operation is the employment of biological agents as a weapon system to produce casualties or damage. A group of larger organisms, capable of caring a disease-producing micro-organism to an individual or from one individual to another, are known as vectors and also can be considered for use in biological operations. These vectors include flies, misquotes, fleas, ticks, and lice.

8.5 HOW THE ENEMY MAY ATTACK YOU
The following are examples of munitions that a modem enemy may use against you in biological warfare. These munitions are regarded as sound methods of conducting operations. However, other means of attack are also possible and may be used by an enemy to achieve surprise.

1. SABOTAGE
2. FREE BALLOONS
3. GENERATORS
4. AIRPLANE SPRAY
5. VECTORS

When biological agents are inhaled, reaching the stomach through consumption of contaminated food or water, or are introduced through the skin, incapacitating or fatal diseases can result. Protecting yourself so that you can continue your job against an enemy (foreign or domestic) using biological agents is your primary concern. To protect yourself against any danger, you must know what the danger is, how it affects you, and how to recognise its presence. Correct individual defensive measures can protect you from many of the hazards you may face from biological agents. Therefore, learning these measures can mean not only that you live to tell about it, but also that your community stays on the job to defeat the enemy.

8.6 WHERE TOXIC AGENTS CAN ENTER YOUR BODY
You may rightly conclude that any equipment that win keep biological agents out of your lungs, out of your eyes, and off your skin will PROTECT you. The types of protective equipment provided and the protective measures needed to block the entry of biological agents into your body are described in the chapters which follow. As a well-trained resident of North America, you must know how to use your protective equipment, and how to make the most of any shelter you may have. Using this knowledge, you will be prepared to protect yourself against the weapons of Germ warfare and, at the same time, to carry on your job.

An important consideration in protecting yourself and continuing your job in any future conflict is to realise that the danger of chemical and biological operations may exist simultaneously or separately. The enemy will use any weapon or any combination of weapons which he thinks will put you and your community out of action. This means that he may use chemical weapon and then follow up with a biological attack. He may use toxic chemical weapons to contaminate certain areas in the hope of making our citizens more vulnerable to biological attack. He may use biological agents to inflict personnel losses, hoping to lower your community's defensive power a