Editing Biological hazard (section)

== Levels of biohazard ==
{{anchor|Biohazard level}}
{{Main|Biosafety level}}
[[File:Sharps Container.jpg|thumb|200px|right|Immediate disposal of used needles into a [[sharps container]] is standard procedure.]]
[[File:Army trainers teach NHS medics how to put on Ebola safety suits (15650293350).jpg|thumb|200px|right|NHS medics practice using protective equipment used when treating [[Ebola]] patients]]

The United States [[Centers for Disease Control and Prevention]] (CDC) categorizes various diseases in levels of biohazard, Level 1 being minimum risk and Level 4 being extreme risk. Laboratories and other facilities are categorized as BSL ([[Biosafety Level]]) 1–4 or as ''P1'' through ''P4'' for short (Pathogen or Protection Level).{{citation needed|date=March 2023}}
* '''Biohazard Level 1:''' Bacteria and viruses including ''[[Bacillus subtilis]]'', [[Canidae|canine]] [[hepatitis]], ''[[Escherichia coli]]'', and [[varicella]] ([[chickenpox]]), as well as some cell cultures and non-infectious bacteria. At this level precautions against the biohazardous materials in question are minimal, most likely involving gloves and some sort of facial protection.
* '''Biohazard Level 2:''' Bacteria and viruses that cause only mild disease to humans, or are difficult to contract via [[aerosol]] in a lab setting, such as hepatitis [[hepatitis A|A]], [[hepatitis B|B]], and [[hepatitis C|C]], some [[influenza A]] strains, [[Human respiratory syncytial virus]], [[Lyme disease]], [[salmonella]], [[mumps]], [[measles]], [[scrapie]], [[dengue fever]], and [[HIV]]. Routine diagnostic work with clinical specimens can be done safely at Biosafety Level 2, using Biosafety Level 2 practices and procedures. Research work (including co-cultivation, virus replication studies, or manipulations involving concentrated virus) can be done in a BSL-2 (P2) '''facility''', using BSL-3 practices and procedures.
* '''Biohazard Level 3:''' Bacteria and viruses that can cause severe to fatal disease in humans, but for which vaccines or other treatments exist, such as [[anthrax]], [[West Nile virus]], [[Venezuelan equine encephalitis]], [[Severe Acute Respiratory Syndrome|SARS coronavirus]], [[Middle East respiratory syndrome|MERS coronavirus]], [[SARS-CoV-2]], Influenza A [[H5N1]], [[hantaviruses]], [[Cholera]], [[tuberculosis]], [[typhus]], [[Rift Valley fever]], [[Rocky Mountain spotted fever]], [[yellow fever]], and [[malaria]].
* '''Biohazard Level 4:''' Viruses that cause severe to fatal disease in humans, and for which vaccines or other treatments are ''not'' available, such as [[Bolivian hemorrhagic fever]], [[Marburg virus]], [[Ebola virus]], [[Lassa fever virus]], [[Crimean–Congo hemorrhagic fever]], and other [[viral hemorrhagic fever|hemorrhagic]] diseases, as well as [[Nipah virus]].<ref>{{Cite journal |last1=Tigabu |first1=Bersabeh |last2=Rasmussen |first2=Lynn |last3=White |first3=E. Lucile |last4=Tower |first4=Nichole |last5=Saeed |first5=Mohammad |last6=Bukreyev |first6=Alexander |last7=Rockx |first7=Barry |last8=LeDuc |first8=James W. |last9=Noah |first9=James W. |date=1 April 2014 |title=A BSL-4 High-Throughput Screen Identifies Sulfonamide Inhibitors of Nipah Virus |journal=Assay and Drug Development Technologies |volume=12 |issue=3 |pages=155–161 |doi=10.1089/adt.2013.567 |pmid=24735442 |pmc=3994909}}</ref> [[Variola virus]] ([[smallpox]]) is an agent that is worked with at BSL-4 despite the existence of a vaccine, as it has been [[Eradication of infectious diseases|eradicated]] and thus the general population is no longer routinely vaccinated. When dealing with biological hazards at this level, the use of a [[positive pressure personnel suit]] with a segregated air supply is mandatory. The entrance and exit of a Level Four biolab will contain multiple showers, a vacuum room, an [[ultraviolet]] light room, [[autonomous detection system]], and other safety precautions designed to destroy all traces of the biohazard. Multiple airlocks are employed and are electronically secured to prevent    doors from both opening at the same time. All air and water service going to and coming from a [[Biosafety level#Levels|Biosafety Level 4]] (P4) lab will undergo similar decontamination procedures to eliminate the possibility of an accidental release. Currently there are no bacteria classified at this level.