Biological weapons consist of pathogenic microbes such as bacteria, viruses, rickettsia, and others that are poisonous to people, animals, plants, and food supplies. These poisonous microbes can also be carried by insects, ticks, rodents, agricultural pests, and other biological agents. The difference between the chemical weapons and the biological weapons is that the chemical agents cause direct injury; the biological weapons cause disease, which results in injury.

Excerpt from PRINCIPLES OF PROTECTION, The US Handbook of NBC Weapon Fundamentals and Shelter Engineering Design Standards, Fifth Edition, 2001, Walton W. McCarthy, The American Civil Defense Association.

BIOLOGICAL WEAPONS

Biological weapons consist of pathogenic microbes such as bacteria, viruses, rickettsia, and others that are poisonous to people, animals, plants, and food supplies. These poisonous microbes can also be carried by insects, ticks, rodents, agricultural pests, and other biological agents. The difference between the chemical weapons and the biological weapons is that the chemical agents cause direct injury; the biological weapons cause disease, which results in injury.

BACTERIA

The "bacteria caused" diseases produced by biological weapons that can be expected during wartime are bubonic plague, malignant anthrax, meliodosis, brucellosis, tularemia, and cholera.
Bacteria can be killed and controlled by disinfectants, boiling, and destroyed by sunlight. Some forms however, such as anthrax and tetanus, are transformed into spores which have a great resistance to disinfectants, boiling, and sunlight. Low temperatures and freezing do not affect bacteria. Bacteria are visible only under a microscope, since their size ranges from .5 to 5.0 microns. Under ideal conditions, they can multiply by simple division every 20 to 30 minutes.

VIRUSES

The viruses that may be dispersed during wartime as a result of biological weapons are: smallpox, equine, encephalomyelitis, denque fever, yellow fever, and psittacosis. These microbes are the smallest organisms. Their size is approximately a hundred thousand times smaller than bacteria and they cannot be seen using an ordinary microscope. Unlike bacteria, viruses require living tissue to multiply. Viruses are also resistant to drying and freezing.

RICKETTSIA

The diseases caused by rickettsia that may be dispersed during wartime as a result of biological weapons are: Typhus, Q fever, Rocky Mountain Spotted Fever, and Tsutsugamushi disease. These microbes are approximately the same size as bacteria but require infected tissue to survive and reproduce.

FUNGI

The fungi that cause diseases and may be dispersed during wartime as a result of biological weapons are: coccidial mycosis, nocardiosis, and blastomycosis. Fungi are like bacteria but are resistant to sunlight and more resistant to disinfectants.

TOXINS

The toxins that cause disease that may be dispersed during wartime as a result of biological weapons are: botulism, tetanus, and diptheria. Some microbes themselves are not poisonous but produce toxins that are. Microbes that produce toxins that are poisonous are listed above. Although there are over l,000 toxins that are able to produce damage to people,animals, and plants, only a few can be delivered as biological weapons.

ANIMALS

The diseases that may be dispersed during wartime as a result of biological weapons used against animals are: hoof-and mouth disease, large horn cattle plague, pig plague, African swine plague, malignant anthrax, glanders and brucellosis.

AGRICULTURE

The diseases that may be dispersed during wartime as a result of biological weapons used against agricultural products are: wheat rust, pyriculariosis, and potato phytophthora.

The choice of biological weapons depends on a number of factors such as: the immunity of the population to resist infection, the level of sanitary conditions, the state of preventative medical treatment and anti-epidemic decontamination facilities, the living conditions of the people at the target site, and the season of the year.

With biological contamination, the sickness does not develop immediately. There is an incubation period in which the disease takes time to develop before disabling the person. The incubation period depends on the biological agent and the general physical condition of the person. Of particular importance are the diseases that can be transmitted from an infected person to a healthy person such as bubonic plague, cholera, and smallpox. This condition must be considered by the shelterist before taking any people into the shelter that were not part of the original group of shelterists.

PERSISTENCE

The time that the biological agent is active and dangerous varies greatly. The persistence varies from several weeks, if carried by mosquitoes, fleas, flies, and lice, to several years if carried by mites. Mites are the extreme because they are capable of bearing offspring with the disease, rather than dying from the disease themselves. Rodents, such as rats and mice, can carry fleas which spread the disease faster and farther, although these rodents die from the disease just as humans do. In postwar periods, insecticides can be used to control or eradicate the majority of insects that may be carrying the disease. Insects can also contaminate food, just as fallout does. The food that comes into contact with insects, insecticides, and fallout must be washed thoroughly. All dead bodies, whether animal or human, should be buried.

METHOD OF DISPERSAL

The method of dispersing biological warfare agents is similar to the chemical warfare agents, except that drinking water supplies can be contaminated locally by introducing contaminants applied by a person at the site.