Hey everybody Dr. O In this video I wanna talk about BSL- level or Bio Safety levels. So the reason why this is important in microbiology is because it determines what kind of percasiouns we need to take if we’re working with certain microbes. So obviously in the labs that I teach we hang around in the bsl-1 and occasionally into the bsl-2 level but I actually wanna walk through each of these levels here and give you a few more examples than the book does as far as the different levels. But as you can see here. Bsl-1 is gonna be your lowest risk microbes you really don’t need to take any special precautions for most of these labs we don’t even have to require um gloves and eye protection and these kind of things obviously those are always a smart idea and as we trap bsl-2 would be the highest level that we ever work with in our labs bsl-3 and then bsl-4 is gonna be where you have to take super special percussions. So lets go ahead and walk through each of these. So ill just read this bsl-1 microbes are not known to cause disease in healthy hosts and pose minimal risk to workers and the environment. So the example here is the non pathogenic strains of e.coli so obviously e.coli 015787 or the other enterohemorrhagic strains of e.coli would be much higher up on the list but these are the ones that you really don’t need to be super concerned with now im still always worried about the potential for um what are called opportunistic pathogens so let’s say you have cuts on your hands we’re gonna take special percussions there if your immunal compromise we’ll take special percussions there but in general these are pretty safe. Uh couple more examples because this is how I like to work I like to actually expose you to pun intended I guess low level bsl-1 organisms that can still teach you about the much more dangerous strains. So obviously we can learn a lot about um the more dangerous strains of E.coli by looking at the non-pathogenic strains same thing with um micro bacterium smegmatis we usually use that organism instead of obviously working with its cousin micro bacterium tuberculosis so we can learn about the acid fast organisms that way and then bacillus subtilis would be a relative of bacillus ataraxis which causes anthrax but obviously bacillus subtilis is a soil organism its actually um found in a lot of probiotics so instead of being dangerous its actually uh uh appears to be a beneficial organism so those are the kinds of organisms we work with in the lab to make sure that your safe I’m much more concerned about your safetly then anything alright uh bsl-2 microbes are typically indigenous and are associated with the diseases of varying severity. They pose moderate risk to workers and the environment. So you see staphylococcus aureus as an example here um these are much safer then the higher level organisms but you still do need to be careful with them ill give you a couple of examples of bsl-2 organisms streptococcus pneumoniae which is still the leading cause of community acquired pneumonia on the planet it kills somewhere in the neighborhood of 1.4 – 1.5 million humans a year. So this organism is no joke but for healthy people being super cautious in a labatory environment it doesn’t appear to be that big of a threat. Another good example is enterococcus faecalis this is uh becoming a much more serious nocacomial or healthcare associate infection but working in the lab its still classified as the bsl-2 level. Okay bsl-3 organisms biosafety level 3 microbes are indigenous or exotic and cause serious or potential potentially lethal diseases through respiratory transmission. So obviously you need to be super care-careful here um taking extra percussions to make sure you don’t breathe them in but these are generally diseases where there are treatments available there are vaccines these types of things. So the example here is mycobacterium tuberculosis another example of a bsl-uh 3 organism would be yersinia pestis which is the cause of the plague the black death nobody wants to get that. Alright your bsl-4 organisms microbes are dangerous and exotic posing a high risk of aerosol-transmitted infections which are frequently fatal without treatments or vaccines. Few labs are at this level. So like we’ll you know we’ll never be um looking at any of these organisms so the examples they gave here are ebola and Marburg which I think Marburg is actually more dangerous than ebola as crazy as it is to say um the lassa virus would be a bsl-4 organism um the vari variola virus which causes smallpox would be bsl-4 organism so that’s actually kinda of a interesting one because it is a bsl-4 organism but not all bsl-4 labs get to work with it theres uh there are just a handful of labs in the entire planet in the sov in Russia and here in the U.S that get to um work with small pox so alright or the causative agence in small pox so those are your bsl or biofatey lab levels for microbiology have a wonderful day be blessed.