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BiologyBiology8,414 views·Updated 22 Aug 2026·2 pages

What Are Communicable Diseases and How They Spread

Communicable diseases are infectious illnesses caused by pathogensthat can...

1
of 2
Communicable diseases – page 1

Transmission of Communicable Diseases

This page discusses the various routes of transmission for communicable diseases, highlighting how pathogens spread from one host to another.

Water-borne transmission occurs when pathogens are picked up by drinking or bathing in contaminated water.

Example: Cholera, a bacterial infection, is spread through drinking water contaminated with the cholera bacterium.

Airborne transmission involves pathogens carried in the air, which can be breathed in by potential hosts. Some airborne pathogens are carried in droplets produced when an infected person coughs or sneezes, known as droplet infection.

Vocabulary: Droplet infection refers to the spread of pathogens through small liquid particles expelled from an infected person's respiratory tract.

Direct contact transmission happens when pathogens are transferred through touching contaminated surfaces, including skin.

Example: Athlete's foot, a fungal infection, is commonly spread by direct contact with contaminated surfaces.

Sexual contact is another form of direct contact that can transmit pathogens between individuals.

Understanding these transmission routes is essential for implementing effective prevention strategies and controlling the spread of communicable diseases. By identifying the specific transmission method for each pathogen, public health measures can be tailored to interrupt the chain of infection and protect populations from disease outbreaks.

2
of 2
Communicable diseases – page 2

Types of Pathogens and Their Characteristics

Communicable diseases are caused by various types of pathogens, each with unique characteristics and methods of causing illness. This page explores the four main categories of pathogens: bacteria, viruses, protists, and fungi.

Bacteria are very small cells that can reproduce inside the human body. They cause illness by producing toxins that damage cells and tissues.

Vocabulary: Toxins are poisonous substances produced by living organisms.

Viruses are not cells but are extremely tiny particles that reproduce rapidly inside the body. They invade host cells and use the cell's machinery to replicate themselves.

Example: When a virus-infected cell bursts, it releases many new viruses, causing cell damage and illness.

Protists are single-celled eukaryotes, some of which are parasites. These parasites live on or inside other organisms and can cause damage to their hosts.

Definition: A vector is an organism that transfers a pathogen to another organism without getting the disease itself.

Fungi can be single-celled or have a body made up of hyphae, which are thread-like structures. These hyphae can penetrate human skin and plant surfaces, causing diseases.

Highlight: Fungi can produce spores, which are reproductive units that can spread to other plants and animals, potentially causing infection.

Understanding the differences between bacteria, viruses, fungi, and parasites is crucial in health and social care settings, as each type of pathogen requires different prevention and treatment approaches.

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BiologyBiology8,414 views·Updated 22 Aug 2026·2 pages

What Are Communicable Diseases and How They Spread

Communicable diseases are infectious illnesses caused by pathogens that can easily spread from one person to another. This summary explores the types of pathogens and diseases they cause, their characteristics, and transmission methods.

  • Pathogensare micro-organisms that enter the...
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Communicable diseases – page 1

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Transmission of Communicable Diseases

This page discusses the various routes of transmission for communicable diseases, highlighting how pathogens spread from one host to another.

Water-borne transmission occurs when pathogens are picked up by drinking or bathing in contaminated water.

Example: Cholera, a bacterial infection, is spread through drinking water contaminated with the cholera bacterium.

Airborne transmission involves pathogens carried in the air, which can be breathed in by potential hosts. Some airborne pathogens are carried in droplets produced when an infected person coughs or sneezes, known as droplet infection.

Vocabulary: Droplet infection refers to the spread of pathogens through small liquid particles expelled from an infected person's respiratory tract.

Direct contact transmission happens when pathogens are transferred through touching contaminated surfaces, including skin.

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Understanding these transmission routes is essential for implementing effective prevention strategies and controlling the spread of communicable diseases. By identifying the specific transmission method for each pathogen, public health measures can be tailored to interrupt the chain of infection and protect populations from disease outbreaks.

2
of 2
Communicable diseases – page 2

Sign up to see the content. It's free!

  • Access to all documents
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By signing up you accept Terms of Service and Privacy Policy

Types of Pathogens and Their Characteristics

Communicable diseases are caused by various types of pathogens, each with unique characteristics and methods of causing illness. This page explores the four main categories of pathogens: bacteria, viruses, protists, and fungi.

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Viruses are not cells but are extremely tiny particles that reproduce rapidly inside the body. They invade host cells and use the cell's machinery to replicate themselves.

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Protists are single-celled eukaryotes, some of which are parasites. These parasites live on or inside other organisms and can cause damage to their hosts.

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Understanding the differences between bacteria, viruses, fungi, and parasites is crucial in health and social care settings, as each type of pathogen requires different prevention and treatment approaches.

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