(Module 5) Communicable Diseases Flashcards
Differences between the two types of diseases
Communicable diseases: these can be spread e.g the flu and a cold
Non communicable: these cannot be spread e.g heart disease
Can be got by a deficiency, a body disorder or a genetic inheritance
Other factors which can affect health
Diet Stress Life situations e.g: Where you live Your gender How many kids you have How far your local dump is Access to health care
What are microorganisms which cause disease called
Pathogens
What types can pathogens be
Bacteria
Fungi
Protist
Viruses
What are the most common pathogens in plants vs animals
Animal: bacteria and viruses
Plants: viruses and fungi
What are the differences between bacteria and viruses
Basically, bacteria are cells of their own, but single celled, whilst viruses take control of your cells
Bacteria are prokaryotic
They are single celled organisms that are smaller than plant and animal cells
Bacteria can be good, we have 1/2 kg of bacteria
More good bacteria than bad
Viruses are even smaller, and cause diseases in all types of living organism
Have regular shapes
How pathogens cause disease
Bacteria divide rapidly by splitting into 2
They may produce toxins (poisons) which make you feel ill
They can directly damage the cell
Viruses take over the cells of the body
They live and reproduce in the cells, damaging and destroying them
Common symptoms of diseases
High temperature
Headaches
Rashes
They are caused by the ways the body responds to the cell damage and toxins produced by the pathogens
How are pathogens spread for humans
A: by air
In humans, droplets of the pathogens from the breathing system are spread by sneezing, coughing or talking, and are breathed in by another
B: direct contact
Diseases can be spread by sexual relations, cuts, scratches and needle punctures
C: by food/water
Diseases can be spread by eating raw, undercooked or contaminated food. As well, drinking water containing sewage
Pathogens enter the body through the digestive system
How are pathogens spread for plants
A: by air
For plants, virus, bacteria and fungal spores are spread in the air from one plant to another
B: direct contact
If part of an infected plant is left in a field, it can infect a completely new plant. Animals can also carry plant diseases
C: water
Fungal spores in water can spread diseases
What did Igual Semmelweis do
He noticed some medical students deliver a baby after dissecting a body without washing their hands. More mums died in pregnancy through medical students than mid wives
He also saw a doctor die with symptoms identical to childbed after cutting himself while dissecting a body
He asked medical students to wash their hands before delivering babies
Doctors were against this at the start
Other preventing diseases discoveries
Louis Pasteur discovered microorganisms caused diseases. He also created vaccines
Joseph Lister started using antiseptic chemicals to destroy pathogens before they caused infection in operating theatre
As microscopes improved, people could see pathogens
How to prevent the spreading of communicable diseases
Hygiene:
Washing hands, cleaning kitchen surfaces, maintaining agricultural machinery
Isolating infected individuals:
The less healthy people who visit someone ill (especially one with a very serious disease) the better
Destroying or controlling vectors:
Vectors are things like mosquitos, house flies or rats (and aphids for plants, and beetles). If those vectors are destroyed, than less diseases are carried
Vaccines
How do vaccines work
A dead or harmless form of a pathogen is injected, so the body recognises the antigen of the pathogen, so if a real, dangerous version of pathogen enters the body the body will recognise it and act quickly.
Examples of viral diseases and facts
Measles:
Main symptoms are a fever and red skin rashes
Can cause blindness, brain damage or even be fatal
No cure, but vaccines are now common and conditions have improved enough in the UK
HIV into aids:
1.5 million infected worldwide
Spread by sexual contact and the exchange of bodily fluids
First symptoms are just a mild flu, so most don’t recognise it
It attacks the immune system, remains hidden, up until the immune system is too weak to fight back. From there, it becomes aids
No cure or vaccine, but can be stopped spreading by condoms or not sharing needles
Use of antiretroviral drugs stops the development of aids, making them live normal. But uncommon in South Africa.
Tobacco mosaic virus:
Attacks plants.
Destroys cells in leaves, which stops plant growth as those cells don’t photosynthesise
Cannot be treated or cured, but farmers grow TMC immune plants
