Infection

Infections

The presence and growth of harmful microorganisms in the body.

Pathology

The study of the causes and effects of diseases.

Microorganisms

Tiny living organisms, such as bacteria, viruses, and parasites, that can cause infections.

Emerging infections

Newly identified diseases that are increasing in incidence or geographic range.

COVID

A respiratory illness caused by the novel coronavirus SARS-CoV-2, first identified in 2019.

AIDS

Acquired Immunodeficiency Syndrome, a disease caused by the human immunodeficiency virus (HIV) that weakens the immune system.

Cholera

An infectious disease caused by the bacterium Vibrio cholerae, resulting in severe diarrhea and dehydration.

Prion

An infectious agent made up of misfolded proteins that can cause neurodegenerative diseases.

Zika

A viral infection transmitted by mosquitoes, associated with birth defects in babies born to infected mothers.

Avian flu

A type of influenza virus that primarily affects birds but can also infect humans.

Host defense

The body's natural mechanisms to protect against pathogens, including barriers like skin and mucous membranes.

Inflammation

The body's response to infection or injury, characterized by redness, swelling, heat, and pain.

Immunity

The ability of the body to resist and fight off infections, often through the production of antibodies.

Pathogenicity

The ability of a microorganism to cause disease.

Opportunism

When a microorganism takes advantage of a weakened host to cause disease.

Pathogenic

Microorganisms that are normally nonpathogenic but become disease-causing due to decreased human host resistance.

Virulence

The capacity of a pathogen to cause severe disease.

Agent host interaction

Interactions between a microorganism and the host's defensive mechanisms that can result in disease.

Zoonoses

Infections that are harbored in animals and can spread to humans.

Incubation period

The period between exposure to an infectious agent and the onset of symptoms.

Prodromal stage

The stage of infection where nonspecific symptoms are present, indicating the onset of illness.

Invasion period

The stage of infection where specific signs and symptoms of the disease are evident.

Convalescence

The stage of infection where the immune system and inflammatory response lead to resolution and recovery.

Fever

A symptom of infection characterized by an elevated body temperature.

Acute phase response

The body's initial response to infection, characterized by the release of chemicals that increase body temperature.

Blood brain barrier

A protective barrier that separates the blood vessels in the brain from the surrounding brain tissue.

Autonomic neurons

Neurons that regulate involuntary bodily functions, such as temperature regulation.

Febrile response

The body's response to elevated temperature, often caused by infection, which helps slow down bodily functions to aid in recovery.

Endocrine response

The body's response to stress or infection, which involves the release of hormones to prepare for fight or flight.

Acute phase response

A metabolic response by the liver to an infection or inflammation, which activates systems to support the inflammatory response.

C-reactive protein (CRP)

A protein used as an indicator of the acute phase response in the body, often elevated during inflammation.

Colonizing

The process by which microorganisms establish contact and entry into the body.

Invasion

The process by which microorganisms use mechanisms to evade or invade the immune system and enter the body.

Biofilm

A structure formed by microorganisms, such as bacteria or fungi, that allows them to attach, grow, and potentially cause recurrent infections.

Dissemination

The spread of microorganisms from one area of the body to another, often facilitated by virulence factors.

Virulence factors

Factors produced by microorganisms that enhance their ability to cause disease or spread within the body.

HPV

A virus that is sexually transmitted and can cause cervical cancer.

Cervical dysplasia

Abnormal changes in the cells of the cervix that can lead to cervical cancer.

STIs

Sexually transmitted infections, such as chlamydia, that are transmitted through sexual contact.

Bacterial infection

An infection caused by bacteria, which are prokaryotes with cell walls.

Fungal infection

An infection caused by fungi.

Protosol infection

An infection caused by protosols.

Cocci

Round-shaped bacteria.

Bacilli

Elongated-shaped bacteria.

Spirochetes

Spiral-shaped bacteria.

Gram stain

A stain used to determine if bacteria are gram positive or gram negative based on their cell wall characteristics.

Gram positive

Bacteria that retain the purple color in the gram stain, indicating a different cell wall structure.

Gram negative

Bacteria that retain the pink color in the gram stain, indicating a different cell wall structure.

Lipopolysaccharides (LPS)

Structures present in the outer membrane of gram negative bacteria that are toxic and can cause an acute immune response.

Endotoxins

Toxins released by gram negative bacteria when they break down, causing harm to the body.

Exotoxins

Toxins released by bacteria that are toxic to the body.

Aerobic

Bacteria that can grow in the presence of air.

Anaerobic

Bacteria that can grow in the absence of oxygen.

Bacteremia

Presence of bacteria in the blood.

Septicemia

Bacteremia that causes infectious disease.

Phagocytosis

Process by which immune cells engulf and destroy bacteria or viruses.

Gram positive bacteria

Bacteria that appear purple in the gram stain.

Gram negative bacteria

Bacteria that appear pink in the gram stain.

Gram stain

A laboratory technique used to differentiate bacteria into two groups based on their cell wall composition.

Staph aureus

A type of bacteria that is normally found on the skin and can cause various infections depending on its location and virulence factors.

Exotoxins

Toxins produced by bacteria that can cause severe skin conditions or food poisoning.

Pneumonia

An infection of the lungs, which can be caused by Staph aureus bacteria.

Septic shock

A life-threatening condition caused by an overwhelming immune response to a severe infection, particularly gram-negative bacteria.

Fungi

Microorganisms that can cause superficial infections, often opportunistic in immunosuppressed individuals.

Candidiasis

A fungal infection caused by Candida, which can lead to severe mucosal infections in immunosuppressed individuals.

Protozoa

Unicellular parasites that can cause diseases in humans and animals.

Helmets

Multicellular parasites, such as worms, that can infect hosts.

Host

The person or animal, including humans, that develops the disease caused by a parasite.

Vector

The organism that carries the parasite but does not develop the disease itself.

Life cycle

The sequence of stages that a parasite goes through, including reproduction and transmission to new hosts.

Toxoplasma

A parasite that can cause toxoplasmosis, which can affect humans and can be transmitted through contact with cat feces or consumption of contaminated meat.

Malaria

A disease caused by a parasite transmitted through the bite of infected mosquitoes.

Virus

Obligatory intracellular microorganisms that require a host cell to replicate and cause disease.

Tissue specific

Viruses that can only infect specific types of cells due to their ability to bind to specific receptors.