Biosafety levels

This level places emphasis on primary and secondary barriers that protect personnel working in contiguous areas. All laboratory manipulations should occur in BSCs or other enclosed equipment such as a gas-tight aerosol-generation chamber. Secondary barriers for this level include controlled 

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It is an aerobic, gram-positive, spore-forming, rod-shaped bacterium. Dry spores are stable for decades. Spores are stable in water for up to 2 years and are resistant to chlorine at purification concentrations. It is endemic in many countries of the world, particularly in tropical and subtropical areas. This is a biosafety level 2 agent. 

It is a gram-negative, spherical (0.4-0.6 fim diameter) bacterium. Survival of the bacteria outside the host depends on the source infected fluid from eggs—52 h bird droppings—a few days bird feed—2 months glass—15 days and straw—20 days. The natural reservoir is birds. This is a biosafety level 2 agent. It is highly communicable from infected birds to people. 

It is an aerobic, gram-negative, nonmotile, nonsporing, coccobacillus that requires cystine for growth. The organism can remain viable for weeks in soil, water, carcasses, and hides. It is resistant for months at temperatures of freezing or below. The natural reservoir is rodents, particularly rabbits and hares. This is a biosafety level 2 agent. 

It is an aerobic, gram-negative, nonmotile, nonsporing, rod-shaped bacterium. It can survive in the environment for up to 2 months in sheltered positions. It is normally a disease of horses. It is a rare and sporadic disease in humans, but it is transmissible by direct contact with sick animals or infected materials. The natural reservoirs are horses, donkeys, and mules. This is a biosafety level 3 agent. 

It is an aerobic and facultatively anaerobic, gram-negative, motile, nonsporing, rod-shaped bacterium. It can survive outside a host on the skin for up to 20 min, in dust for up to 30 days, and in feces for up to 62 days. Does not naturally occur in animals. This is a biosafety level 2 agent. 

It is a gram-negative, nonsporing, oval-shaped bacterium. It is primarily a zoonotic disease of birds and mammals, with humans as incidental hosts. Often seen in hamsters, guinea pigs, and chinchillas. It has also been associated with enterocolitis and diarrhea in young sheep at pasture that are debilitated from factors such as starvation and cold weather. This is a biosafety level 2 agent. 

It is normally found in tropical areas throughout the world. The natural reservoirs are mosquitoes and primates. Mosquitoes remain infective for life. Monkeys infected with this virus usually have no symptoms or only mild ones. This is a biosafety level 3 agent. 

It is normally found in southern and Eastern Europe, Central Asia, the Mediterranean, northwestern China, Africa, and the Indian subcontinent. The natural reservoirs are ticks and numerous animal species. Animals (e.g., cattle, sheep, goats, horses, pigs, hares, hedgehogs) infected with this virus usually have no clinical symptoms or suffer only a mild illness. The hemorrhagic fever is highly pathogenic and notable for aerosol transmission. This is a biosafety level 4 agent. 

It is normally found in the Caribbean, the South Pacific, Southeast Asia, the West Indies, India, and the Middle East. The natural reservoirs are humans, primates, and mosquitoes. Does not produce disease in animals. This is a biosafety level 2 (classical) or 3 (hemorrhagic) agent. Typically a fulminant, nonlethal disease however, it may progress to a hemorrhagic form. Stabile outside a host in dried blood and exudates for up to several days at room temperature. 

It is normally found in Africa. The natural reservoir is unknown. It can survive in blood specimens for several weeks at room temperature, but does not survive for long periods after drying. Also produces disease in primates with symptoms similar to those seen in humans. This is a biosafety level 4 agent. 

Is a member of the New World hemorrhagic fever viruses normally found in Brazil. The natural reservoir is the rice rat (Oryzomys) and the virus is shed in their urine. Infection occurs after inhalation of dust contaminated with excreta from infected rats or from aerosol of animal blood or fluids. Does not produce disease in animals. This is a biosafety level 3 agent. 

It is normally found only in Australia. The natural reservoir is fruit bats (Pteropus species), however, there is no evidence of direct transmission from bats to humans. Special precautions should be taken when examining a horse suspected of having the disease or performing a necropsy. Although it is not considered highly communicable, this is an enhanced biosafety level 3 agent. 

It is a viral hemorrhagic fever normally found in South Asia. The natural reservoirs are ticks, monkeys, rodents, and porcupines. Ticks remain infective for life. This is a biosafety level 4 agent. 

Influenza is one of the most common infectious diseases in humankind and is one of the most contagious airborne infectious diseases. The natural reservoirs are humans, horses, swine, and birds. It can survive outside a host in dried mucous for several hours. This is a biosafety level 2 agent. 

It is present in most of Europe, throughout Africa, the Middle East, most of Asia, and the Americas. It is a highly lethal disease that can affect all warm-blooded animals. This is a biosafety level 2 agent unless there is a high risk of aerosol production then it should be treated as a biosafety level 3 agent. 

Generally found in East Africa and the Middle East. The primary natural reservoir is not known. The disease is transmitted by mosquitoes, which remain infective for life. Infection is also transferred directly to mosquito eggs. It can survive in dried discharges for extended periods. This is a biosafety level 3 agent. 

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