Background: The single most poisonous variety is typically foodborne, but it could be developed as an aerosol weapon. A Journal of the American Medical Association report traces its first use to Japanese conquest of Manchuria in the 1930s. The Soviet Union and Iraq both produced weaponized botulinum toxins in violation of international treaties.
Effects: Initial symptoms, such as blurred vision and difficulty swallowing and speaking, take effect in 24 to 36 hours. The toxin paralyzes muscles, leading to respiratory failure and death.
Treatment: The Centers for Disease Control and Prevention maintain a botulism anti-toxin supply.
Background: A government study estimated that about 200 pounds of anthrax released upwind of Washington, D.C., could kill up to 3 million people. The disease is not contagious. The Centers for Disease Control and Prevention website provides detailed questions and answers.
Effects: Early symptoms include fever, malaise, cough and respiratory distress. Shock and death can follow within 36 hours.
Treatment: If given early enough, antibiotics can prevent exposed people from falling sick. The vaccine is reserved for military use.
Background: Nearly 19,000 cases of history's most feared contagious disease were reported worldwide between 1980 and 1994. Lethal cases in the U.S. are extremely rare.
Effects: Symptoms occur within one to six days after inhaling the pneumonic form. High fever, cough and labored breathing lead to respiratory failure and death. The Journal of the American Medical Association estimates that historically epidemics of plague produce death within 2-6 days if the infected persons go untreated.
Treatment: Rapid use of antibiotics can be effective. A vaccine is not currently being produced in the United States.
Background: This highly contagious disease killed more than 500 million people in the 20th century before medicine eradicated it in 1977. Vaccinations stopped in 1980.
Effects: Early symptoms such as fever, headache and nausea occur for about 12 days. A chickenpox-like rash spreads across the body, hardening into blisters. One-third of victims die.
Treatment: There is none, but smallpox can be prevented. The U.S. government initially maintained a stockpile of 12 million doses of vaccine, enough for one out of 23 Americans. After the Sept. 11 attacks, however, the government increased its stockpile.
Background: The U.S. military studied this infectious organism as a weapon in the 1950s and 1960s. Effects: Fever, chills, headache and weakness occur in three to five days. Resulting inflammation and hemorrhaging of the airways can lead to death.
Treatment: Without antibiotics, one-third of those infected die. The Food and Drug Administration is currently reviewing a vaccine.
Viral hemorrhagic fevers
Background: Natural occurrences of these series viruses are rare and confined to isolated areas of the earth. However, several powers, including the Soviet Union, Iraq, North Korea and the United States, have studied weaponization of viruses like Ebola hemorrhagic fever, Lassa fever, hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome. The National Center for Infectious Diseases maintains a database of naturally occurring outbreaks and other detailed information.
Effects: Fever, muscle aches and diarrhea occur in three to five days. Fluids hemorrhage out of tissues and orifices. Depending on the strain, 30 percent to 90 percent of victims die if untreated.
Treatment: Some of these diseases respond to antiviral drugs, but those are in short supply.
Background: Ricin, a toxin derived from the beans of the castor plant, is more powerful than cyanide and twice as deadly as cobra venom. In 1977 Bulgarian agents used an umbrella tipped with 450 micrograms of ricin to kill dissident Georgi Markov in London. More recently U.S. troops found traces of ricin in caves in Afghanistan. Ricin is stable enough to be disseminated as an aerosol, an injection or as a food and water contaminant.
Effects: Early symptoms include fever, cough, difficulty breathing and nausea. Later stages include profuse sweating, skin turning blue, low blood pressure and respiratory failure. Death would occur in 36 to 72 hours.
Treatment: There is no treatment for ricin. Doctors can only treat the symptoms.
Biological Agents/Diseases web link
Valuable resource for information on biological agents