Biological Agents

The Centers for Disease Control and Prevention (CDC) has determined that the following biological agents may be used for a biological attack:

Anthrax

Anthrax is a disease that is caused by a bacterium named Bacillus anthracis. B. anthracis belongs to a large group of bacteria which are capable of surviving extreme conditions. These organisms produce "spores" as a survival mechanism. Spores can tolerate extreme temperatures and dryness. Spores have been known to re-generate into active or vegetative bacteria after being dormant for many years.

Where did Anthrax originate?

B. anthracis has been found in soils in various parts of the world. It has infected people sporadically throughout history. It was commonly known as "wool sorter's disease" because it was usually manifest in agricultural workers handling wool or other animal products in areas that had high concentrations in the local soils.

How does Anthrax infect humans?

Anthrax has in three primary forms depending upon the type of exposure. The most severe is inhalation anthrax. This occurs when a significant number or the spores are inhaled into the lungs. Spores begin to grow and infect the lungs. Without treatment, death usually occurs in a few days.

Anthrax can also infect the skin. The organisms are sometimes are able to colonize in the skin usually through a small a cut or lesion. This type of infection initially produces a sore sometimes mistaken for a spider or insect bite. Later, it turns into a dark or black sore. This is the most frequent natural occurrence of human exposure. Skin or cutaneous infections may or may not be fatal. Treatment is usually effective for this type of anthrax.

The third type of anthrax infection is gastrointestinal. This may happen when a significant number or B. anthracis organisms or spores are ingested with contaminated food or water. This form of anthrax is very uncommon. It can also be fatal if not diagnosed and treated.

How is Anthrax treated?

Anthrax is treatable with early detection and anti-biotic therapy. Although Anthrax is rarely seen, the medical community is more aware of it and its symptoms than ever before. Anthrax is not transmitted from person to person. Treatments include specific antibiotics. It is very important to follow recommended procedures for taking prescribed medications. Spores formed by B. anthracis (Anthrax) may survive for several days in the body after antibiotic therapy is started. Symptoms may not be present, but viable spores are capable of remaining for many days. Complete treatments usually is takes up to 60 days.

Natural outbreaks of Anthrax are highly unlikely. If an individual were exposed to a suspicious powder or spray, there should be enough time to determine if B. anthracis is present and receive treatment prior to onset of the disease.

For a more specific information on Anthrax: www.bt.cdc.gov

Botulinum toxin

Botulism is a disease caused by the ingestion of a toxin produced by a bacterium called Clostridium botulinum.

Where did Botulism originate?

C. botulinum is an anaerobic spore forming organism commonly found in heavy, wet soils or mud where oxygen levels are low. The organism produces a highly poisonous toxin. Fortunately, the toxin is rarely found in high concentrations in nature, and is readily destroyed by chemical sanitizers (i.e. chlorine) or heat. No cases of waterborne botulism have ever been documented.

How does Botulism infect humans?

Botulism in humans is most closely associated with canned food items. Modern requirements for commercial food canning and processing have all but eliminated cases in the canning industry. Most outbreaks of botulism are due to improper home food canning techniques. Consumption of low acid foods not properly heated during canning or re-heated prior to serving most often are to blame. Isolated cases of botulism probably would indicate a problem with a food item rather than a terrorist event.

A type of botulism referred to as "infant botulism" is caused by the ingestion of Clostridia organisms or spores that colonize the intestinal tract of infants or very young children. These organisms are then capable of producing toxins in the child. This type of illness is treatable, but can be severe or fatal. As children mature and their immune systems improve, the likelihood of infant botulism diminishes.

How is Botulism treated?

Botulism is almost always fatal if not treated. The toxin has the ability to stop nerve synapses from functioning properly. The toxin thereby stops muscle functions and leads to paralysis. This usually starts with muscles in the neck and will continue to the point of no breathing activity. Therapy for a person with botulism includes artificial respiration for several days until unassisted breathing can resume. An anti-toxin may also be used as soon as the illness is diagnosed and the specific strain of C. botulinum is determined.

For more specific information on botulinum toxin or botulism: www.bt.cdc.gov

Viral Hemorrhagic Fevers

These diseases are placed into one category based on their symptoms even though a wide variety of viruses are involved. The following are the four groups as designated by the Centers for Disease Control and Prevention (CDC):

Where did Viral Hemorrhagic Fevers originate?

These types of viruses are not native to North America. Most are found in third world countries in Africa, Asia, and South America.

How do Viral Hemorrhagic Fevers infect humans?

They have usually been transmitted by direct contact with animals, insect bites, or from person to person. People in the United States sometimes have contracted these illnesses by traveling to areas where they are more prevalent.

Viral hemorrhagic fever symptoms are usually manifested between 2-21 days after exposure. Symptoms are fever, rashes, body aches, headaches, and fatigue. It may worsen with time and may be followed by bleeding problems. Natural outbreaks of these diseases often result in serious illness or death.

How are Viral Hemorrhagic Fevers treated?

Viral hemorrhagic fevers are not treatable with antibiotics. In cases caused by Arenaviridae and Bunyaviridae treatments of Ribavirin with interferon have been shown to be successful. Filoviridae and Flaviridae viruses have no know effective treatments. A widely used vaccine is effective against yellow fever, however, the short incubation time of the illness make it ineffective if given after exposure.

Efforts are being made to develop vaccines and better treatments for these categories of diseases. Prevention from exposure is the best way to limit spreading. If an outbreak of hemorrhagic fever did occur, isolation of those with the disease would be required. Medical personnel caring for patients would need to use personal protective equipment. Ventilation measures to limit airborne exposure would be required.

Plague

Plague is a disease has caused severe death and suffering in various parts of the world in past centuries. The mention of plague still stirs fear and panic in most people.

Where did Plague originate?

Plague is caused by a bacterium known as Yersinia pestis. Naturally occurring Y. pestis outbreaks are found in wild rodent populations. Isolated cases of plague most likely indicate exposure to infected rodent populations.

Here in South Central Utah, natural sources have infected humans in recent years. Fortunately most cases are rapidly diagnosed and successfully treated. Public education of people in areas with high rodent populations has helped lessen the frequency.

How does Plague infect humans?

The organism maybe transmitted to humans or animals by fleas, insects, or direct contact with infected individuals. Plague is manifested in two forms. Bubonic plague is often the form the disease takes in naturally occurring outbreaks. Symptoms include swelling of the lymph nodes, severe fever, and malaise. Local swelling may become extreme. Swollen infected areas are referred to as "buboes".

The second form the disease is referred to as pneumonic plague. This form occurs from inhalation of the Y. pestis organism and subsequent lung infections and severe pneumonia. Due to the low natural incidence of this type of infection, pnuemonic plague with an unknown origin usually indicate intentional exposure.

Pneumonic plague is considered to be much more contagious than the bubonic form. Precautions to avoid direct contact with patients or aerosolized organisms should be taken (i.e. gloves, breathing protection, etc.). If left untreated the illness usually is fatal.

How is Plague treated?

Plague is usually successfully treated with antibiotics. The early detection of the disease and proper treatment are very important. Any person that has had direct face-to-face contact with a person known to have pneumonic plague should receive antibiotics as prophylaxis. Symptoms of the disease usually occur within 1 to 6 days after exposure.

Smallpox

Smallpox is a viral disease that is similar to chickenpox. It is spread by contact with infected humans. The early stages of smallpox may be confused with chickenpox, however as the disease progresses it becomes different in the type of rash develops and the areas of the body infected. Smallpox is fatal in about 30 percent of manifest cases.

Where did Smallpox originate?

Smallpox has infected humans throughout recorded time. It was eliminated from human populations about 20-30 years ago. The effects of smallpox were very devastating to many populations. Death rates for those with smallpox have been about 30 percent. In the past, most people would eventually encounter smallpox during their lifetime. The smallpox disease is caused by a virus known as variola.

How does Smallpox infect humans?

The only known source of naturally occuring smallpox was from other infected humans. It was usually transmitted by aerosalized droplets in areas near infected people. Symptoms of usually begin to show between 12 to 14 days after exposure. They begin as a rash around the mouth and nasal areas. Pustules begin to form. The rash or pustules become more severe as they spread to the face, trunk, arms and legs. A unique feature of smallpox is that pustules are formed on the soles of the feet and the palms of the hands. Chicken pox rashes or pustules are not present in these particular areas.

How is Smallpox treated?

Viral illnesses typically do not respond to antibiotics. In some instances, physicians may prescribe antibiotics to control secondary bacterial infections. Smallpox is no exception. There is no cure for smallpox once contracted. Treatments are only given to lessen the effects of the illness and lessen suffering.

Vaccinations and modern medical procedures have been highly successful in eliminting the disease in humans. Vaccination programs were stopped after the disease was eradicated. Vaccines, while highly effective, must be administered prior to onset of illness. Precautions for individuals with immune disorders must be taken, since the vaccine consists of a live virus.

Once an outbreak of smallpox is identified, the best method to prevent it from spreading is by isolating infected individuals. It is highly contagious and special steps must be taken to avoid infection from patients.

For more specific information on smallpox: www.bt.cdc.gov

Tularemia

What is Tularemia?

Tularemia is an infectious disease that is caused by a bacteria (francisella tularensis). The bacteria is found in animals, especially rodents, rabbits and hares.

Is Tularemia naturally found in the United States?

Yes. It is a widespread disease of animals. About 200 cases of tularemia in humans are reported every year in the United States, mostly in persons living in the south-central and western states. Nearly all cases are in rural areas and are associated with the bites of infected ticks, flies, or handling infected rodents, rabbits or hares.

How is Tularemia Spread?

People can get tularemia many different ways. They can get the bacteria through the bite of an infected insect, handling infected animal carcasses, or eating or drinking contaminated food or water, or by breathing in the bacteria. Tularemia is not spread from person to person. People with Tularemia do not need to be isolated.

Why are we concerned about Tularemia as a bio-weapon?

The bacteria Francisella tularensis is highly infectious. If used as a bio-weapon, the bacteria would likely be made airborne for exposure by inhalation. Persons who breathe it in would have severe breathing problems if not treated.

What are the signs and symptoms of Tularemia?

Depending on how the person was exposed to tularemia, the bacteria may cause skin ulcers, swollen lymph nodes, inflamed eyes, sore throat, oral ulcers or pneumonia. If the bacteria was inhaled symptoms would be quick fever, chills, headache, muscle aches, joint pain, dry cough and weakness.

Can Tularemia be treated with antibiotics?

Yes. After potential exposure or diagnosis of Tularemia, early treatment with antibiotics (such as doxycycline or ciprofloxacin) has been proven to be effective.

What Can Be Done to Prevent Tularemia?

The following precautions can help protect people from tularemia.

Avoid drinking, bathing, swimming or working in untreated water where infection may be common among wild animals. Use rubber gloves when skinning or handling wild animals, especially rabbits.
Avoid being bitten by deer flies and ticks by wearing light-colored long -sleeved shirts and long pants so ticks can be easily seen. Use insect repellent. Walk in the middle of trails so weeds do not brush against you. Check yourself every two to three hours for ticks, and check pets often for ticks.