Infections of the Respiratory System

Why is this system important?

The respiratory system is the most commonly infected system

Health care providers will see more respiratory infections than any other type

Overview

The Respiratory System

A major portal of entry for infectious organisms

It is divided into two tracts – upper and lower respiratory tracts

The division is based on structures and functions in each part.

The two parts have different types of infections

Labeling Assignment

Now that you know your respiratory system is divided into 2 parts, the upper and the lower respiratory tracts, label the diagram with the correct components that make up each tract.

Use the following words: Alveolus Throat (pharynx) Bronchus Lung Mouth Larynx Nasal Cavity Wind pipe (trachea) Nose Bronchiole

After labeling each component draw a line where you believe the upper and lower respiratory tracts

The Respiratory Tract

The Upper Respiratory Tract Nasal cavity, nose, mouth, pharynx, Infections are fairly common Usually nothing more than an irritation

The Lower Respiratory Tract Larynx, Trachea, Lungs, Bronchus, Bronchiole, Alveolus Infections are more dangerous Can be very difficult to treat

Respiratory functions

1. supplies the body with oxygen and disposes of carbon dioxide

2. filters inspired air

3. produces sound

4. contains receptors for smell

5. rids the body of some excess water and heat

6. helps regulate blood pH

Pathogens of the Respiratory System

Respiratory pathogens are easily transmitted from human to humanThey circulate within a community Infections spread easilyhttp://abcnews.go.com/WNT/video/best-sneeze-22258478

Some respiratory pathogens exist as part of the normal flora

Others are acquired from animal source, water, air etc

Fungi are also a source of respiratory infectionUsually in immunocompromised patients

Pathogens of the Respiratory System cont’d

Some pathogens are restricted to certain sites

Legionella only infects the lungOther pathogens cause infection in multiple sites

Streptococcus can cause: Middle ear infectionsSinusitisPneumonia

Defenses of the Respiratory System

The body has a variety of host defense mechanisms

Innate immune response the cells and mechanisms that defend the host from infection by other organisms, in a non-specific manner

Adaptive immune It is adaptive immunity because the body's immune system prepares itself for future challenges

Defenses of the Respiratory System

The respiratory system has significant defenses

The upper respiratory tract has: Mucociliary escalator As air usually enters the body through the nose (a

preferable point of entry) Cilia (fine hairs) protect against dust and other

particles from the air Particles that may slip through the cilia are caught

in the thick, sticky, mucous lining of the nasal cavity

Air is warmed in the nasal cavity and finally moisture is added

Coughing Secretory IgA

The lower respiratory tract has:Alveolar macrophages IgA

Defenses of the Respiratory System cont’d