Microbes and disease
A few harmful microbes, for example less than 1% of bacteria, can invade our body (the host) and make us ill. Microbes cause infectious diseases such as flu and measles.
There is also strong evidence that microbes may contribute to many non–infectious chronic diseases such as some forms of cancer and coronary heart disease. Different diseases are caused by different types of micro-organisms. Microbes that cause disease are called pathogens.
|Infectious disease||Microbe that causes the disease||Type of microbe|
|Whooping cough||Bordatella pertussis||Bacterium|
|Bubonic plague||Yersinia pestis||Bacterium|
|TB (Tuberculosis)||Mycobacterium tuberculosis||Bacterium|
|Athletes’ foot||Trichophyton mentagrophytes||Fungus|
It is important to remember that:
- A pathogen is a micro-organism that has the potential to cause disease.
- An infection is the invasion and multiplication of pathogenic microbes in an individual or population.
- Disease is when the infection causes damage to the individual’s vital functions or systems.
- An infection does not always result in disease!
To cause an infection, microbes must enter our bodies. The site at which they enter is known as the portal of entry.
Microbes can enter the body through the four sites listed below:
- Respiratory tract (mouth and nose) e.g. influenza virus which causes the flu.
- Gastrointestinal tract (mouth oral cavity) e.g. Vibrio cholerae which causes cholera.
- Urogenital tract e.g. Escherichia coli which causes cystitis.
- Breaks in the skin surface e.g. Clostridium tetani which causes tetanus.
To make us ill microbes have to:
- reach their target site in the body;
- attach to the target site they are trying to infect so that they are not dislodged;
- multiply rapidly;
- obtain their nutrients from the host;
- avoid and survive attack by the host’s immune system.
An infection can be seen as a battle between the invading pathogens and host. How does the immune system work?
Routes of transmission
Find out how you can pick up germs and pass them on to others.
Just a shot in the arm – what do vaccines do?
Antibiotics are powerful medicines that only fight bacterial infections.
- What is negative entropy?no_redirect=1
- Do women have lighter brains
- How do I create my own channel
- Do schizophrenics ever self harm
- What race has the tallest average height?no_redirect=1
- What is your unforgettable hotel experience
- What is the golden client in SAP
- What are fluorinated greenhouse gases
- Do gold diggers exist in India
- How will Brexit affect the fishing trade
- Why doesnt the US respect Pakistans sovereignty
- Is Chinese Kung Fu powerful
- What happen to unused e mail accounts
- Can you use a post office box
- What screams Im from Kuala Lumpur
- What does Slovakia look like
- Why is a metal sheet roof better
- Why is the Japanese Navy so huge
- What s the culture in Chicago like