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Major Biological Agents Facts
 

expand              Anthrax
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How is anthrax diagnosed?
Anthrax is diagnosed by isolating B. anthracis from the blood, skin lesions, or respiratory secretions or by measuring specific antibodies in the blood of suspected cases.

 
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What are the symptoms of anthrax?
Symptoms of anthrax usually develop in less than seven days of exposure and most cases occur within 48 hours. Cutaneous anthrax occurs when the bacteria enter the skin through a cut or abrasion. Skin infection begins as a raised, itchy bump which becomes a blister and then an ulcer-like lesion appears with a black area in the center. Death is rare with cutaneous anthrax when treated appropriately with antibiotics.
 
Inhalation anthrax occurs when the spores are inhaled and get into the lungs. Initial symptoms of inhalation anthrax include fever, fatigue, cough and difficulty breathing. Congestion is not usually associated with inhalation anthrax. Without immediate treatment, inhalation anthrax is often fatal.
 
Intestinal anthrax is caused by the consumption of meat from animals that have died from anthrax. Symptoms include nausea, loss of appetite, vomiting and fever. The symptoms are followed several days later by abdominal pain, vomiting of blood and severe diarrhea.

 
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When should I be concerned about a letter or package?

The U.S. Postal Service has provided some typical characteristics which should trigger suspicion of letters or parcels:

  • Have any powdery substance on the outside.
  • Are unexpected or from someone unfamiliar to you.
  • Have excessive postage, handwritten or poorly typed address, incorrect titles or titles with no name, or misspellings of common words.
  • Are addressed to someone no longer with your organization or are otherwise outdated.
  • Have no return address, or have one that can't be verified as legitimate.
  • Are of unusual weight, given their size, or are lopsided or oddly shaped.
  • Have an unusual amount of tape.
  • Are marked with restrictive endorsements, such as "Personal" or "Confidential."
  • Have strange odors or stains.

 
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Do I need a vaccine or antibiotics to protect myself against anthrax?

The anthrax vaccine is not available or recommended for the public. This vaccine is administered to military personnel at high risk for exposures in combat settings. For additional information, consult the current U.S. Public Health Service's Advisory Committee on Immunization Practices recommendations on anthrax vaccination.

Physicians can prescribe effective antibiotics to treat anthrax. If left untreated, the disease can be fatal. The Department does not recommend the use of antibiotics for people who have no symptoms suggestive of anthrax or known exposure. In addition, using antibiotics without a physician's prescription may cause serious reactions and potentially dangerous interference with other medications.


 
expand              Botulism
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How would botulism be used as a bioterrorism weapon?
A fourth type of botulism, not mentioned above, is inhalational botulism. This form does not occur in nature, however, the Department of Defense has documented the production of botulinum toxin biowarfare weapons by Iraq and the former Soviet Union. These weapons would distribute aerosolized botulinum toxin, which would result in inhalational botulism. Bioterrorism also could come in the form of food contamination, resulting in food-borne botulism.

 
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How is botulism diagnosed?
Physicians may consider the diagnosis if the patient's history and physical examination suggest botulism. However, these clues are usually not enough to allow a diagnosis of botulism. There are other diseases, such as stroke, that have similar symptoms, and special tests may be needed to exclude these other conditions. The most direct way to confirm the diagnosis is to demonstrate the botulinum toxin in the patient's serum or stool by injecting serum or stool into mice and looking for signs of botulism. The bacteria can also be isolated from the stool of persons with food-borne and infant botulism. These tests can be performed at CDC and will soon be available at the Arizona State Health Laboratory.

 
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How can botulism be prevented?
Persons who do home canning should follow strict hygienic procedures to reduce contamination of foods. Oils infused with garlic or herbs should be refrigerated. Potatoes which have been baked while wrapped in aluminum foil should be kept hot until served or refrigerated. Because the botulism toxin is destroyed by high temperatures, persons who eat home-canned foods should consider boiling the food for 10 minutes before eating it to ensure safety. Instructions on safe home canning can be obtained from county extension services or from the US Department of Agriculture. Because honey can contain spores of C. botulinum and this has been a source of infection for infants, children less than 12 months old should not be fed honey. Honey is safe for persons 1 year of age and older. Wound botulism can be prevented by promptly seeking medical care for infected wounds and by not using injectable street drugs.

 
expand              Brucellis
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Where does brucellosis occur?
The infection occurs worldwide, and is most common in the Mediterranean countries of Europe and Africa, the Middle East, India, central Asia, Mexico, and Central and South America. In the United States, most cases are reported from California, Florida Texas, and Virginia. In Arizona, 35 cases have been identified over the last twenty years. Most of these cases are associated with consumption of unpasteurized dairy products brought into Arizona from Mexico.

 
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What are the symptoms of brucellosis?
This incubation period for this disease can be highly variable, but symptoms usually appear within one to two months after exposure. Brucellosis is characterized by a fever which may be continuous, intermittent or irregular. Some other possible symptoms include headache, weakness, sweating, chills, arthralgia (pain in the joints), depression, weight loss and generalized aching. This disease may last for days, months, or as long as a year if untreated.

 
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What is the treatment for brucellosis?
Doctors can prescribe antibiotics, including tetracycline and tetracycline plus streptomycin, for brucellosis. Early diagnosis leading to rapid treatment is needed to prevent chronic infection.

 
expand              Cholera
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How does a person get cholera?
A person may get cholera by drinking water or eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water. The cholera bacterium also may live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of cholera, and a few persons in the United States have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico. The disease is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

 
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What is the risk for cholera in the United States?
n the United States, cholera was prevalent in the 1800s but has been virtually eliminated by modern sewage and water treatment systems. However, as a result of improved transportation, more persons from the United States travel to parts of Latin America, Africa, or Asia where epidemic cholera is occurring. U.S. travelers to areas with epidemic cholera may be exposed to the cholera bacterium. In addition, travelers may bring contaminated seafood back to the United States; food-borne outbreaks have been caused by contaminated seafood brought into this country by travelers. Cholera cases rarely occur in Arizona and are usually associated with travelers to countries with ongoing cholera problems.

 
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Can cholera be treated?
Cholera can be simply and successfully treated by immediate replacement of the fluid and salts lost through diarrhea. Patients can be treated with oral re-hydration solution, a prepackaged mixture of sugar and salts to be mixed with water and drunk in large amounts. This solution is used throughout the world to treat diarrhea. Severe cases also require intravenous fluid replacement. With prompt re-hydration, fewer than 1% of cholera patients die. Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as re-hydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

 
expand              Ebola
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How common is the disease?
Until recently, only a few outbreaks of Ebola hemorrhagic fever among people had been reported. The first two outbreaks were in 1976: one in Zaire and one in western Sudan. These were large outbreaks, resulting in more than 550 cases and 340 deaths. A third outbreak, in 1979 in Sudan, was smaller, with 34 cases and 22 fatalities. More recently, outbreaks have also occurred again in Zaire in 1995-6, with 352 cases and 276 deaths, and in Gabon in 1996, with 60 cases and 45 deaths. During each of these outbreaks, a majority of cases occurred in hospital settings under the challenging conditions of the developing world. These conditions, including a lack of adequate medical supplies and the frequent reusing of needles and syringes, played a major role in the spread of disease. The outbreaks were quickly controlled when appropriate medical supplies and equipment were made available and quarantine procedures were used.

 
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What is the reservoir for Ebola?
The source of the Ebola virus in nature remains unknown. In an attempt to identify the source, investigators tested thousands of specimens from animals and arthropods captured near the outbreak areas, but their efforts were unsuccessful. Monkeys, like humans, appear to be susceptible to infection and may serve as a source of virus if infected. The outbreak in Gabon was linked to eating a chimpanzee and a single human case in Ivory Coast in 1994 was associated with chimpanzees.

 
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How is the Ebola virus spread from person to person?
Ebola virus is spread through close personal contact with a person who is very ill with the disease. In previous outbreaks, person-to-person spread frequently occurred among hospital care workers or family members who were caring for an ill person infected with Ebola virus.
 
Transmission of the virus has also occurred as a result of hypodermic needles being reused in the treatment of patients. Reusing needles is a common practice in developing countries, such as Zaire and Sudan, where the health care system is underfinanced. Medical facilities in the United States do not reuse needles.
 
Ebola virus can also be spread from person to person through sexual contact. Close personal contact with persons who are infected but show no signs of active disease is very unlikely to result in infection. Patients who have recovered from an illness caused by Ebola virus do not pose a serious risk for spreading the infection. However, the virus may be present in the genital secretions of such persons for a brief period after their recovery, and therefore it is possible they can spread the virus through sexual contact.

 
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How do health officials control outbreaks?
Previous outbreaks of Ebola hemorrhagic fever have been limited. These outbreaks were successfully controlled through the isolation of sick persons in a place requiring the wearing of mask, gown, and gloves; careful sterilization of needles and syringes; and proper disposal of waste and corpses.

 
expand              Plague
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How common is plague in the U.S.?
Human plague in the United States has occurred as mostly scattered cases in rural areas (an average of 10 to 20 persons each year) in the western half of the U. S.. Generally, plague is most common in the southwestern states, particularly New Mexico and Arizona. Globally, the World Health Organization reports 1,000 to 3,000 cases of plague every year.

 
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What is the concern for plague and bioterrorism?
Plague has been used as a bioweapon of war dating back to the Middle Ages, when foreign invaders would catapult the corpses of plague victims over castle walls. During WWII, the Japanese released millions of plague infected fleas over villages in China. Both the United States (until the 1960s) and the former Soviet Union (until the 1990's) developed plague as a biowarfare agent. During the 1980's the Soviet Union maintained a quota of twenty tons of weaponized plague every year. Other countries have been, or are suspected of, developing this agent as a weapon.

 
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What is the basic transmission cycle?
Fleas become infected by feeding on rodents, such as the chipmunks, prairie dogs, ground squirrels, mice, and other mammals that are infected with the bacteria Y. pestis. Infected fleas transmit the plague bacteria to humans and other mammals during the feeding process. The plague bacteria are maintained in the blood systems of rodents.

 
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What are the signs and symptoms of plague?
A typical sign of the most common form of human plague is a swollen and very tender lymph gland, accompanied by pain. The swollen gland is called a "bubo" (hence the term "bubonic plague"). Bubonic plague should be suspected when a person develops a swollen gland, fever, chills, headache, and extreme exhaustion, and has a history of possible exposure to infected rodents, rabbits, or fleas. Infection of the lungs, either through droplet inhalation or secondary infection, causes pneumonic plague, a severe respiratory illness. Pneumonic plague patients may experience high fever, chills, cough, and breathing difficulty, and expel bloody sputum.

 
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What is the mortality rate of plague?
About 14% (1 in 7) of all plague cases in the United States are fatal. The fatality rate for untreated cases of pneumonic plague is nearly 100%

 
expand              Q Fever
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How is Q Fever spread?
The organisms are inhaled along with dust from areas contaminated by placental tissues, birth fluids, and excreta of infected animals. Direct contact with infected animals and other contaminated materials, such as wool, straw, fertilizer, and laundry of infected people has been associated with spread of the disease. Raw milk from infected cows contains organisms and may be another source of infection. Direct transmission from blood or bone marrow transfusion also has been reported.

 
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Who can get Q Fever?
Anybody can get Q Fever but it is found most often in areas where animals may be infected. Laboratory personnel, who work with C. burnetii, veterinarians, meat workers, sheep and dairy workers and farmers are at the most risk.

 
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What are the symptoms of Q Fever?
After an incubation period of 2 to 3 weeks, some people have a sudden onset of illness with chills, severe headache, weakness, fatigue, and severe sweats. Others may not have any noticeable symptoms or have a general "fever of unknown origin." The fatality rate is generally less than 1%, even in untreated cases, although it may be higher in individuals who go on to develop endocarditis, a potential long term manifestation of Q fever.

 
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What is the treatment for Q Fever?
Treatment is usually with antibiotics such as tetracycline or chloramphenicol started during illness and continued for several days after fever is gone.

 
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How can Q Fever be prevented?
Prevention is through education of the public on sources of infection and the need for proper disinfection and disposal of animal products after the birthing process. Those operating cow and sheep sheds, barns and laboratories which use such animals should restrict access to these areas. Only pasteurized milk from cows, goats and sheep should be consumed.

 
expand              Ricin
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What are the signs of ricin intoxication?
When inhaled as a small particle aerosol, ricin would likely produce symptoms within 8 hours. Fever, cough, difficulty breathing, nausea, and chest tightness are followed by profuse sweating, skin turning blue, low blood pressure, and finally respiratory failure and circulatory collapse. Time to death would likely be 36-72 hours, depending on the dose received.

 
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Can ricin intoxication be treated?
No specific treatment exists, and care is thus supportive treatment of symptoms.

 
expand              Smallpox
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Is Arizona prepared for a smallpox outbreak?
Arizona has been testing bioterrorism response plans for over two years now, at both the state and local level. Recently, the Department participated in a statewide training exercise to test the coordination and distribution of the National Pharmaceutical Stockpile, which could be utilized in an emergency. The Arizona Department of Health Services has submitted a plan to the US. Centers for Disease Control and Prevention outlining the State's response to a suspected case of smallpox. A plan has also been submitted which details a gradual approach to the vaccination of health care workers and public health workers who would investigate a possible smallpox outbreak and would treat suspect cases of smallpox. The Department is working with all county health departments and other stakeholders to ensure coordination of bioterrorism response plans throughout the state.

 
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If someone comes in contact with smallpox, how long does it take to show symptoms?
The incubation period is about 12 days (range: 7 to 17 days) following exposure. Initial symptoms include high fever, fatigue, and head and back aches. A characteristic rash, most prominent on the face, arms, and legs, follows in 2-3 days. The rash starts with flat red lesions that evolve at the same rate. Lesions become pus-filled after a few days and then begin to crust early in the second week. Scabs develop and then separate and fall off after about 3-4 weeks.

 
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How is smallpox spread?
In the majority of cases, smallpox is spread from one person to another by infected saliva droplets that expose a susceptible person having face-to-face contact with the ill person. In very rare circumstances, aerosol transmission has occurred between people sharing the same airspace, such as within a hospital ward. People with smallpox are not infectious until the onset of the rash. During the early stages of the rash, persons infected with smallpox are most infectious, because that is when the largest amount of virus is present in saliva. However, some risk of transmission lasts until all scabs have fallen off.
 
Contaminated clothing or bed linen could also spread the virus. Special precautions need to be taken to ensure that all bedding and clothing of patients are cleaned appropriately with bleach and hot water. Disinfectants such as bleach and quaternary ammonia can be used for cleaning contaminated surfaces.

 
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The smallpox virus is fragile and in the event of an aerosol release of smallpox, all viruses will be inactivated or dissipated within 1-2 days. Buildings exposed to the initial aerosol release of the virus do not need to be decontaminated. By the time th
Report suspected cases of smallpox or suspected intentional release of smallpox to your local health department. The local health department is responsible for notifying the state health department, the FBI, and local law enforcement. The state health department will notify the CDC.

 
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Is there a test to indicate whether smallpox is in the environment like there is for anthrax?
Scientists believe that if smallpox virus is released as an aerosol and not exposed to UV light, it may persist for as long as 24 hours or somewhat longer under favorable conditions. However, by the time patients become ill, which takes about 10 days to 12 days after infection with the virus, and it has been determined that an aerosol release of smallpox virus had occurred, there would be no viable smallpox virus left in the environment to detect. Trying to detect the virus everywhere at all times without any indications of any illness in people would not be feasible.
The occurrence of smallpox infection among people who handled laundry from infected patients is well documented, and it is believed that virus in such material remains viable for extended periods. In this situation, the virus could be detected in the environment, but investigators would already know it was there because of the presence of the associated illness.
 
In studies conducted during the smallpox eradication program and by surveillance for cases in newly smallpox-free areas it was reasoned that if the virus were able to persist in nature and infect humans, there would be cases occurring for which no source could be identified. Cases of this type were not observed. When cases were found, there were human cases in people who had direct contact with another infected person.

 
expand              Smallpox Vaccine
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Is Arizona receiving any of the nation's smallpox vaccine?
The Arizona Department of Health Services has recently submitted a plan to the federal government, which outlines the voluntary vaccination of certain public health and health care workers. At the present time no smallpox vaccine is available to this state, but the Federal Government is planning to make the vaccine available to limited groups in our state, according to our smallpox plan.

 
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If I am concerned about a smallpox attack, can I go to my doctor and request the smallpox vaccine?
In the United States, routine vaccination against smallpox ended in 1972. Since the vaccine is no longer recommended, the vaccine is not available. The CDC maintains an emergency supply of vaccine that can be released if necessary.

 
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If people got the vaccination in the past when it was used routinely, will they be immune?
Not necessarily. Routine vaccination against smallpox ended in 1972. The level of immunity, if any, among persons who were vaccinated before 1972 is uncertain; therefore, these persons are assumed to be susceptible. For those who were vaccinated, it is not known how long immunity lasts. Most estimates suggest immunity from the vaccination lasts 3 to 5 years. This means that nearly the entire U.S. population has partial immunity at best. Immunity can be boosted effectively with a single revaccination. Prior infection with the smallpox disease, however, grants lifelong immunity.

 
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Is it possible for people to get smallpox from the vaccination?
No, smallpox vaccine does not contain smallpox virus but another live virus called vaccinia virus. Since this virus is related to smallpox virus, vaccination with vaccinia provides immunity against infection from smallpox virus.

 
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Will the antibiotic ciprofloxacin protect me against smallpox?
No. Because smallpox is a virus, antibiotics such as ciprofloxacin will not fight the smallpox infection. However, smallpox vaccination-even after exposure- is effective in preventing or lessening the severity of the disease.

 
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When will additional smallpox vaccine be ready?
The production of a new, and somewhat safer, smallpox vaccine is currently underway. It is estimated that the new vaccine may be available in late 2003 or early 2004. At the present time, there is enough smallpox vaccine for every American in an emergency. A recent discovery of a large stockpile of effective vaccine, along with evidence that the vaccine can be diluted, ensures that there is enough existing vaccine to respond to a large-scale smallpox outbreak.

 
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If someone had smallpox once, are they immune? Would they need the vaccine?
Most people who have had smallpox disease are protected from the disease for life and do not need to be vaccinated. However, few people living in the United States have had smallpox.

 
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Are diluted doses of smallpox vaccine as effective?
It is possible that diluted (i.e., watered-down) smallpox vaccine may also be effective in providing immunity. The initial results have shown that diluted vaccine at various strengths is still effective in providing immunity to smallpox. It is possible that diluted smallpox vaccine may also be effective as a booster shot. Results from the dilution studies will help make this determination.

 
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Is there a risk of accidental exposure to persons involved in the production of smallpox vaccine?
Persons involved in the production of smallpox vaccine will not contract smallpox because the vaccine does not contain smallpox virus. The vaccine contains another live virus called vaccinia virus. Because vaccinia is closely related to smallpox, vaccination with that virus provides immunity against infection from smallpox virus.
 
However, as with all live-virus vaccines, the vaccinia vaccine does carry some risks. To minimize any risk of infection, the limited number of facilities involved in the production of smallpox vaccine should always observe appropriate biosafety guidelines and adhere to published infection-control procedures and recommendations for working with the vaccine virus strain.

 
expand              Staphylococcal Enterotoxin B
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How is SEB associated with bioterrorism?
SEB was explored as a possible bioweapon by the United States, presumably the former Soviet Union did also. A bioterrorism attack with aerosol delivery of SEB to the respiratory tract would produce a distinct syndrome causing significant illness and potential death. The sabotage of food and/or water with SEB is also thought to be a possibility for terrorist attack. Although an attack with SEB, especially by food contamination, may not cause many fatalities, it could incapacitate 80% of the public in the area of attack. In rare cases, especially with an aerosol attack, the effect of the toxin may be more severe, leading to shock and death.

 
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Is SEB intoxication treatable?
There is no vaccine or antitoxin available to treat SEB before or after exposure. The treatment for SEB once symptoms appear consists of pain relievers and cough suppressants. Additional drug therapies are under investigation. For severe cases which are expected to be rare, more extensive hospital procedures may be needed such as mechanical breathing and replacement of fluid.

 
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How is SEB diagnosed?
There is no specific test available for diagnosing SEB intoxication. There are laboratory findings that may help in the diagnosis, such increases in the number of specific types of white blood cells called neutrophils.

 
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Is SEB intoxication treatable?
There is no vaccine or antitoxin available to treat SEB before or after exposure. The treatment for SEB once symptoms appear consists of pain relievers and cough suppressants. Additional drug therapies are under investigation. For severe cases which are expected to be rare, more extensive hospital procedures may be needed such as mechanical breathing and replacement of fluid.

 
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How is SEB diagnosed?
There is no specific test available for diagnosing SEB intoxication. There are laboratory findings that may help in the diagnosis, such increases in the number of specific types of white blood cells called neutrophils.

 
expand              Tularemia
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How is tularemia associated with bioterrorism?
F. tularensis, like the plague and anthrax bacteria, was weaponized by the U.S. (until the 1960's) and the former Soviet Union (until the 1990's). Other countries have been or are suspected to have weaponized this bacteria. This organism can potentially be produced in either a wet or dry form and introduced by aerosolization or contamination of food and water sources.

 
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How is tularemia spread?
Many routes of human exposure to the tularemia germ are known to exist. The common routes include direct contact with blood or tissue while handling infected animals, through the bite of arthropods (e.g., ticks, mosquitoes), or handling or eating undercooked small game animals (e.g., rabbit). The bacteria can remain viable in frozen rabbit meat for longer than 3 years. Less common means of transmission are drinking or swimming in contaminated water, from animal scratches or bites of animals contaminated from eating infected animals, and inhaling dust from contaminated soil or handling contaminated pelts or paws of animals. Tularemia is not directly transmitted from person to person.

 
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How soon do symptoms appear?
Symptoms generally appear between 1 and 14 days, but usually within 3-5 days.

 
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What can be done to prevent the spread of tularemia?
Rubber gloves should be worn when skinning or handling animals, especially rabbits. Wild rabbit and rodent meat should be cooked thoroughly before eating. Avoid bites of ticks and other arthropods by using standard repellants. Avoid drinking, bathing, swimming or working in untreated water.

 
expand              Viral Hemorrhagic Fever
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What are the reservoirs for viruses that cause VHFs?
Viruses associated with most VHFs are zoonotic. This means that these viruses naturally reside in an animal reservoir host or arthropod vector (insects or ticks). They are totally dependent on their hosts for replication and overall survival. For the most part, rodents and arthropods are the main reservoirs for viruses causing VHFs. The multimammate rat, cotton rat, deer mouse, house mouse, and other field rodents are examples of reservoir hosts. Arthropod ticks and mosquitoes serve as vectors for some of the illnesses. However, the hosts of some viruses remain unknown, including the filoviruses, Ebola and Marburg.

 
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How are hemorrhagic fever viruses transmitted?
Some viruses that cause hemorrhagic fever can spread from person to person, once an initial person has become infected. Ebola, Marburg, Lassa and Crimean-Congo hemorrhagic fever viruses are examples. Usually, viruses causing VHFs are initially transmitted to humans when they come in contact with infected reservoir hosts or vectors. The viruses carried in rodent reservoirs are transmitted when humans have contact with urine, fecal matter, saliva, or other body excretions from infected rodents. The viruses associated with arthropod vectors are spread most often when the vector mosquito or tick bites a human, or when a human crushes a tick. However, some of these vectors may spread virus to animals, livestock, for example. Humans then become infected when they care for or slaughter the animals.

 
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Are there treatments for viral hemorrhagic fever?
Patients receive supportive therapy, but generally speaking, there is no other treatment or established cure for VHFs. Ribavirin, an anti-viral drug, has been effective in treating some individuals with Lassa fever or HFRS. Treatment with antiviral antibody has been used with success in some patients with Argentine hemorrhagic fever.