Purpose of Cells
T-Cells
They can develop long-lasting immunity to specific pathogens, prevent autoimmune reactions, directly attack and kill infected cells, and finally, they activate other cells (like B-cells and macrophages).
Infectious Agent
The pathogen, such as a bacteria, virus, fungus, or parasite, that causes the infection.
Bacteria
Single-celled microorganisms that can reproduce rapidly and cause a variety of infections.
Contact
Used for infections that spread through direct contact with the patient's skin or contaminated surfaces or objects.
Bone Marrow
The primary organ where all blood cells, including lymphocytes, originate. B lymphocytes mature in the bone marrow, while T lymphocytes travel to the thymus.
B-Cells
They produce antibodies that neutralize pathogens, mark them for elimination, and support other immune cells.
Reservoir
The place where the infectious agent lives and multiplies; it can be a person, animal, environment, or object.
Viruses
Smaller than bacteria, they need to invade a host cell to reproduce. They are responsible for illnesses like the common cold, influenza, and measles.
Droplet
Used for infections that spread through respiratory droplets produced when an infected person coughs, sneezes, talks, or vomits.
Thymus
Primary organ where T lymphocytes mature and learn to distinguish between self and non-self.
Natural Killer Cells
They kill cells that have become infected with viruses or have become cancerous.
Portal of Exit/Entry
How the infectious agent leaves and enters the reservoir; examples include the respiratory tract, gastrointestinal tract, skin, or blood.
Fungi
Causes fungal infections, such as athlete's foot, ringworm, and candidiasis. They can be single-celled or multi-celled organisms.
Airborne
Used for infections that spread through small particles in the air that can remain suspended for long periods.
Spleen
A large organ that filters the blood and houses lymphocytes, serving as a site for immune responses to pathogens found in the bloodstream.
Monocytes/Macrophages
They engulf and digest foreign particles, pathogens, and cellular debris.
Mode of Transmission
How the infectious agent is transmitted from the reservoir to the susceptible host; common modes include direct contact, indirect contact, airborne transmission, and droplet transmission.
Parasites
Worms, protozoa, or other organisms that live within or on the body and cause diseases like malaria and tapeworm infection.
Enteric
Used to prevent the spread of germs that can be transmitted through direct or indirect contact with a patient's body fluids, particularly fecal matter.
Lymph Nodes
Neutrophils
They are the first responders to infections, releasing enzymes that help engulf and digest bacteria, fungi, and other foreign particles.
Susceptible Host
The person who is at risk of becoming infected; factors that make a person more susceptible include age, health status, and immune system function.
Prions
Infectious proteins that can cause diseases like mad cow disease.
Tonsils/Adenoids
Organs located in the throat that trap pathogens entering the body through the mouth and nose, playing a role in the immune response to these pathogens