The set of all procedures implemented to reduce the environmental risks and impact of infections associated with viral, bacterial, and fungal pathogens is referred to as biosafety.
Biosafety is therefore based on a code of conduct aimed at acquiring the skills and knowledge necessary to minimize the risks to laboratory personnel and anyone who comes into contact with them during the performance of their activities.
This subject is studied and addressed in the field within biosafety laboratories, where potentially dangerous pathogens are handled and containment systems are designed.
There are four types of biocontainment laboratories: the first two types are basic laboratories (Biosafety 1 and 2), the third type is a containment laboratory (Biosafety 3), and the fourth type is a maximum-containment laboratory (Biosafety 4).
The first level is suitable for activities involving well-characterized agents known not to cause disease in healthy adult humans and with minimal potential hazard to laboratory personnel and the environment (CDC, 1997).
Decontamination procedures at this level are similar in many respects to common precautions against everyday microorganisms (for example, washing hands with antibacterial soap, cleaning all exposed laboratory surfaces with disinfectants, etc.).
Laboratory personnel receive specific training in laboratory procedures and are supervised by a scientist with general training in microbiology or a related science.
The second level is similar to the first and is suitable for activities involving pathogens with moderate potential hazard to personnel and the environment.
It includes various bacteria and viruses that cause only mild illnesses in humans, such as hepatitis A, B, and C, measles, and salmonella.
Research activities (including co-cultivation, virus replication studies, or manipulations involving concentrated viruses) can be carried out in a BSL-2 (P2) facility, using the practices and procedures typical of BSL-3 level.
The third level applies to clinical, diagnostic, teaching, research, and production facilities in which locally produced or externally sourced agents are used that can cause serious or potentially lethal diseases following inhalation.
These include various bacteria, parasites, and viruses that can cause serious or fatal diseases in humans, but for which treatments exist, such as Francisella tularensis , Tuberculosis , Chlamydia psittaci , Yersinia pestis e SARS-CoV-2.
This level is required to work with dangerous and exotic agents that pose a high risk of airborne laboratory-acquired infections, involving agents that cause severe, often fatal diseases in humans for which no vaccines or other treatments are available, such as Ebola, Congo-Crimean hemorrhagic fever, and various other hemorrhagic diseases.
At this level of biological risk, the use of a personal positive-pressure suit with a separate air supply is mandatory.
Entry to and exit from a Level Four biological laboratory involve showers, an airlock, a ultraviolet-light chamber, and other safety measures designed to eliminate all traces of biological risk. Sealed, lockable access points are used, electronically controlled to prevent both doors from being opened simultaneously.
One of the sectors in which this issue is particularly relevant is the food and livestock industry.
