Unit 12: Diseases and Infection
B: Examine the transmission of infectious diseases and how
this can be prevented
Infectious diseases are disorders caused by small organisms - such as bacteria, viruses, fungi,
or parasites. Many microorganisms live in or on our bodies. These organisms are usually
harmful, or beneficial. However, under certain conditions, some small organisms may cause
diseases.
It can transmit those infectious diseases from person to person. Some diseases are caused
by insects or other animals. Other diseases may develop due to eating food or drinking
contaminated water, or because of exposure to small organisms in the environment.
1
,Modes of transmission of diseases
2
, There are so many of modes transmission of diseases such
Routes Diseases
Foodborne & Waterborne Cholera, Typhoid Fever
Air borne SARS, Mumps
Victor Borne Yellow Fever, Dengue, Malaria
Animal Borne Leptospirosis
Blood Borne HIV/AID
Sexually Transmitted Ascariasis, Fungal infections
Recreational Water Tinea, CLM, Legionellosis
Modes of transmission
And it comes with:
1- Direct
o Direct contact
o Droplet spread
2- Indirect
o Airborne
o Vehicle borne
o Vector borne (mechanical or biologic)
Route Example Disease
Direct contact Occurs by skin-to-skin touch, sexual intercourse, and kissing. STDs, Scabies,
Skin infection
Droplet spread Applies to spray with fairly big, short-range sneezing, coughing or even Common cold,
talking aerosols. Droplet distribution is known as direct as it is dispersed Mumps,
over a few feet by direct transfer until the droplets fall to the ground.. Pertussis, strep
throat
Indirect contact Suggests the transfer by floating air particles, non-living objects (vectors) or Skin infections,
animate intermediaries (vectors) of an infectious agent from a source to a Diarrheal disease
host.
Airborne Takes place when the infectious agents are transmitted by air suspended particles Chickenpox,
or droplet nuclei. Airborne dust contains material that has accumulated on Tuberculosis,
surfaces and is resuspended by air currents as well as wind-blowing bacterial Smallpox, SARS,
particles from the ground. Droplet nuclei are smaller than 5 micron diameter dried Anthrax
residues.
Vehicle borne Meat, water, biological products (blood), and fomites (inanimate objects such as Some diarrheal
handkerchiefs, bedding, or surgical scalpels) can indirectly transmit an infectious disease, Hepatitis
agent. b/c
Vector borne These can bring an infectious agent by solely mechanical means, such as Lyme disease,
(mechanical or mosquitoes, fleas and ticks, or can promote growth or changes in the agent. LaCrosse
biologic) encephalitis
3
B: Examine the transmission of infectious diseases and how
this can be prevented
Infectious diseases are disorders caused by small organisms - such as bacteria, viruses, fungi,
or parasites. Many microorganisms live in or on our bodies. These organisms are usually
harmful, or beneficial. However, under certain conditions, some small organisms may cause
diseases.
It can transmit those infectious diseases from person to person. Some diseases are caused
by insects or other animals. Other diseases may develop due to eating food or drinking
contaminated water, or because of exposure to small organisms in the environment.
1
,Modes of transmission of diseases
2
, There are so many of modes transmission of diseases such
Routes Diseases
Foodborne & Waterborne Cholera, Typhoid Fever
Air borne SARS, Mumps
Victor Borne Yellow Fever, Dengue, Malaria
Animal Borne Leptospirosis
Blood Borne HIV/AID
Sexually Transmitted Ascariasis, Fungal infections
Recreational Water Tinea, CLM, Legionellosis
Modes of transmission
And it comes with:
1- Direct
o Direct contact
o Droplet spread
2- Indirect
o Airborne
o Vehicle borne
o Vector borne (mechanical or biologic)
Route Example Disease
Direct contact Occurs by skin-to-skin touch, sexual intercourse, and kissing. STDs, Scabies,
Skin infection
Droplet spread Applies to spray with fairly big, short-range sneezing, coughing or even Common cold,
talking aerosols. Droplet distribution is known as direct as it is dispersed Mumps,
over a few feet by direct transfer until the droplets fall to the ground.. Pertussis, strep
throat
Indirect contact Suggests the transfer by floating air particles, non-living objects (vectors) or Skin infections,
animate intermediaries (vectors) of an infectious agent from a source to a Diarrheal disease
host.
Airborne Takes place when the infectious agents are transmitted by air suspended particles Chickenpox,
or droplet nuclei. Airborne dust contains material that has accumulated on Tuberculosis,
surfaces and is resuspended by air currents as well as wind-blowing bacterial Smallpox, SARS,
particles from the ground. Droplet nuclei are smaller than 5 micron diameter dried Anthrax
residues.
Vehicle borne Meat, water, biological products (blood), and fomites (inanimate objects such as Some diarrheal
handkerchiefs, bedding, or surgical scalpels) can indirectly transmit an infectious disease, Hepatitis
agent. b/c
Vector borne These can bring an infectious agent by solely mechanical means, such as Lyme disease,
(mechanical or mosquitoes, fleas and ticks, or can promote growth or changes in the agent. LaCrosse
biologic) encephalitis
3
