Hi colleagues |
This is the latest version of infection control guideline |
and cleaning procedure instruction |
And the other one is the response plan |
for suspected novel / severe emerging infectious disease |
I understand that many of you are experienced |
but I still hope you can familiarise yourselves with the contents |
especially we have a new member here |
We should look out for each other |
Prevention of infectious diseases? |
You mean wearing mask when having a cold? |
It is not only about mask wearing |
You also have to wash hands, and wash frequently |
How about diarrhoea after eating unclean food? Is it an infectious disease? |
You mean food poisoning? |
All of you are correct, but infectious diseases are not that simple |
Let's watch the video to know more |
Dr Leo Lui, Associate Consultant, Infection Control Branch, Centre for Health Protection |
Dr Lui, could you tell us more about infectious diseases? |
KJ, infectious diseases are diseases that can be spread directly |
or indirectly to humans to cause an infection |
These diseases are caused by pathogens |
(including bacteria, viruses, fungi and parasites) invading our bodies |
The pathogens multiply in the human body and cause damage to normal cells, |
death can ensue in serious situations |
These pathogens can be transmitted from an infective source |
(e.g. patients, animals) to a person through various routes |
causing the person to be infected and fall ill |
What are the routes of transmission for an infectious disease? |
A number of factors must be present simultaneously for a disease to acquire infectivity |
They include pathogens (i.e. infective microorganisms) |
source of infection, mode of transmission and susceptible host |
This process is known as the "chain of infection" |
Routes of transmission can be broadly categorised as contact, droplet and airborne |
Certain infectious diseases can be transmitted by more than one route |
Theoretically, transmission of infectious diseases |
can be prevented by interrupting the chain of infection |
Contact is the most common route of transmission |
Transmission through direct contact refers to person-to-person spread of pathogens |
via direct physical contact, such as by hands |
Transmission through indirect contact |
occurs by coming into contact with contaminated environment or object |
such as sharing of towel |
Most of the multi-drug resistant organisms |
and scabies, which can cause severe skin itchiness |
are examples that are transmitted by the contact route |
Droplet transmission occurs when infectious droplets |
deposit on the mucous membrane of eyes, nose and mouth |
These particles are usually larger than 5 micrometres in size |
hence they do not remain suspended in the air for a prolonged period of time |
and normally do not travel beyond the distance of 1 to 2 metres from the source person |
When the source person coughs, talks or sneezes |
the infectious droplets are generated |
Influenza is an infectious disease transmitted by the droplet route |
When airborne droplet nuclei (usually smaller or equal to 5 micrometres in size) |
containing pathogens remain suspended in the air for a prolonged period of time |
and are inhaled into our respiratory system |
airborne transmission will result |
Examples of infectious diseases transmitted by the airborne route |
include tuberculosis, chickenpox and measles |
Apart from the 3 routes mentioned |
other routes of transmission include bloodborne transmission, sexual transmission |
mother-to-child transmission and vector-borne transmission, etc |