Biohazards Flashcards
What are bacteria?
Organisms composed of simple, naked DNA chromosomes (sometimes two) without a nuclear membrane (prokaryote)
How big are bacteria?
1-5 um
What are examples of bacteria?
E. Coli, TB, syphilis, typhoid
What are viruses?
- Live intracellular parasites
- DNA or RNA and protein coat
How big are viruses?
20-300 nm
What are examples of viruses?
Common cold, polio, rabies, hepatitis
What are fungi?
Digest food outside body by releasing enzymes
What are examples of fungi?
Ringworm, athlete’s foot, histoplasmosis, and aspergillus
What are parasites?
Organisms taking sustenance from a host
What are examples of parasites?
Toxoplasmosis, trichinellosis
What is rickettsia?
A parasite living within the cells of ticks and mites
What are examples of rickettsia diseases?
Rocky Mountain spotted fever, Q fever, murine typhus, sylvatic typhus
Typhus vs typhoid
Typhoid Mary (bacteria) spread via fecal oral route and typhus is a parasite (rickettsia)
What are prions?
Proteins without a nucleus that are infectious
What are prion disease examples?
Bovine spongiform encephalopathy (mad cow), creutzfeldt-jacob disease
What are the most common insect vectors?
Mosquitos and ticks
What is biological risk?
The possibility of developing illness from exposure to a single biohazard agent (depending on susceptibility)
Chain of infection
RETER
Reservoir
Escape from reservoir
Transmission
Entry into new host
Reinfection
BSL 1 lab requirements
Controlled access
Hand washing sink
Sharp hazards warning policy
Personal protective equipment
Laboratory bench
Autoclave
BSL 1 PPE
lab coats, gloves, eye protection) are worn as needed.
BSL 2 lab requirements
Controlled access
Hand washing sink
Sharp hazards warning policy
Physical containment device (lab hood)
Personal protective equipment
Laboratory bench
Autoclave
What is a biosafety level 1 lab
- Defined well characterized organisms
- No known or minimal potential hazards
- No special competence
- Open bench work is allowed
BSL 2
- Endemic agents of moderate risk
- College-level competence
- Access limited when work is in progress
- Supervisor must be competent scientist
BSL 2 lab agent examples
- Hepatitis B virus
- Salmonella
- Toxoplasmosis
In which level of Biosafety would you find controlled access to laboratory, physical separation from access corridors, the lab environment kept in negative pressure, self-closing double doors, and exhausted non-recirculated air?
BSL 3
Which biosafety cabinet provides the greatest level of agent containment and user protection?
BSC Class III
BSL 3 lab requirements
Air tight when disinfecting
Self-closing, double-door access
Controlled access
Personal shower out (risk-based enhancement)
Sharp hazards warning policy
Hand washing sink
Sealed penetrations
Physical containment device
Powered air purifying respirator (risk-based enhancement)
Laboratory bench
Autoclave
Exhaust HEPA filter (risk-based enhancement)
Effluent decontamination system (risk-based enhancement)
What type of toxicant is histoplasmosis?
Fungal / mycotoxin
What animals are histoplasmosis associated with?
Bird and bats - their droppings
Who is more likely to be exposed to histoplasmosis?
Farmers, forestry workers. People who to into caves and the woods.
What type of pathogen is Newcastle Disease?
Zoonotic disease - virus
What animal is associated wit Newcastle Disease?
Zoonotic disease - birds - especially poultry
What is Brucellosis
Zoonotic infection caused by bacteria
Contact with goats, sheep, pigs, camels, and dogs / unpasteurized milk / bodily fluids
Most common zoonotic disease in the world
Psittacosis
Chlamydia psittaci is a type of bacteria that often infects birds. Less commonly, these bacteria can infect people and cause a disease called psittacosis. Psittacosis can cause mild illness or pneumonia (lung infection).
Class 3 biosafety cabinet
A Class III cabinet is defined as a totally enclosed, ventilated cabinet with leak-tight construction and attached rubber gloves for performing operations in the cabinet. These cabinets have a transfer chamber with interlocked doors that allow for sterilization of materials before entering/exiting the glove box.
Class 2 biosafety cabinet
- Ventilated cabinet
- Open front with inward airflow (personnel protection)
- Downward HEPA-filtered laminar airflow (product protection)
- HEPA-filtered exhaust air (environmental protection).
- All biologically contaminated ducts and plenums to be under negative pressure or surrounded by negative pressure ducts and plenums
Class 1 biosafety cabinet
- Are designed with an open front with inward airflow (personnel protection)
- HEPA-filtered exhaust air (environmental protection)
- Air can be recirculated back to the lab or exhausted outside
