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Infectious Agents


Infectious agents is a term that is generally used to describe and encompass any material that can cause an infection that can lead to a disease. These types of materials are largely Bacterial but also largely comprised of Viral, Fungal, Rickettsias, Prions and Parasites. Vulnerability and prevalence depends mostly on geography and climate but in a laboratory setting, almost any agent is habitable under artificial means such as climate and humidity control.

Aerosol and Transmissible Diseases (ATD) Overview

These agents can exist in many areas and depending on their morphology and selectivity, they present unique hazards that must be addressed. Disease causing agents than can be transmitted through inhalation or an aerosol fall under a unique set of OSHA requirements called Aerosol and Transmissible Diseases (ATD) and these agents can be both zoonotic and non-zoonotic. Zoonotic agents are capable of crossing a species boundary such as man to animal or visa versa, whereas non-zoonotic can infect either man or animal but cannot be contracted from one or the other.

Blood borne Pathogens Overview

While aerosols present unique concerns, especially with agents that can generate aerosols easily through mild agitation or spills, many agents are transmissible through contact with bodily fluids such as blood. For these types of agents, we classify them under Blood-borne Pathogens and many of these agents are already household names. 
    • Human Immunodeficient Virus (HIV)
    • Hepatitis B (HepB)
    • Hepatitis C (HepC)
    • Viral Hemorrhagic Fever
Some blood-borne pathogens are not usually transmitted directly through contact with blood but rather by a vector such as an insect. These include:
    • West Nile Virus
    • Malaria
    • Syphilis
    • Brucellosis

Medical Waste Overview

Medical waste disposal is regulated due to the presence of bodily fluids that have the possibility of harboring disease causing agents. Areas that have medical waste include emergency response personnel, medical treatment areas, University Health Center etc.
Please review the Medical Waste Disposal Manual for more detailed information regarding disposal procedures.
View the current Medical Waste Generator/ Treatment Permit


Single celled organisms that largely comprise the kingdom Monera and Prokaryota and generally live off of other organisms. Bacteria lack a cell nucleus unlike mammalian (eukaryotic) cells and reproduce very quickly through either fission or forming spores. Some bacteria cause disease and others secrete toxins that can lead to disease. These pathogenic strains of bacteria are sometimes resistant to antibiotics which makes research involving antibiotic resistance genes a tightly regulated field. Healthy bacteria make up the natural flora of our digestive system and play a large role in the human immune system which ironically fights off infection and disease.


A virus is in a basic sense, a non-living entity, a constant debate among virologists and microbiologists. Typically a virus is a protein capsule that contains genetic material that can be injected into a host genome. Once the infection occurs, the injected genetic material can lay dormant or it may be expressed immediately but what makes viruses so unique is they rely on the host's intracellular machinery to express the injected genes which ultimately code for the production of more viral particles until they destroy their host cell and spread to other neighboring cells. Unfortunately, viruses do not respond to antibiotics but anti and retro-viral medications are available for many viruses. [Return To Top]


Fungus is a eukaryotic multi-celled organism classified as fungi which differs from other kingdoms such as animals, plants and bacteria. Plants and fungi differ in the make-up of their cell walls. Plants have cellulose and fungi have chitin. Common types of fungus include yeasts, mold and mushrooms to name a few. Certain fungi have been used to create antibiotics like penicillin because these fungi can produce bioactive mycotoxins that not only combat various types of bacteria but also susceptible plants and weeds. Early stages of the fungal lifecycle can involve spores which can only be destroyed in high heat, high pressure conditions as they are well adapted to surviving harsh conditions.


Rickettsia is a gram-negative bacterium (pleomorphic) but can only survive inside the cytoplasm of mammalian or eukaryotic cells that serve as a host to the rickettsia. Commonly carried by lice, fleas and ticks, they can often cause disease in humans such as Rocky Mountain spotted fever and typhus. Most rickettsias are susceptible to tetracycline antibiotics.


Prions like viruses are not living and take advantage of the host cellular functions to reproduce. Prions were named by combining "Proteins" and "Infection" because a prion is merely a specific type of mis folded or denatured protein. Once formed, they create accumulations in brain tissue which leads to necrosis of the once healthy tissue and cell death occurs. Prions are responsible for transmissible spongiform encephalopathies in a variety of mammals including bovine spongiform encephalopathy commonly referred to as "mad cow disease". Similarly, Creutzfeld-Jakob Disease (CJD) is the resulting disease in humans. [Return To Top]


Parasites are organisms that require a host to survive. Often times the parasite will obtain a food source from the host but sometimes at the expense of the host, a situation where the parasite robs nutrients from the host. The three most common classes of parasites that can cause disease in humans includes Protozoa, Helminths (worms), and Ectoparasites.