Communicable Diseases & Prevention and Treatment of Disease Flashcards
How can pathogens spread?
Dirty water, contaminated food, airborn, animals, physical contact
What is a communicable disease?
Diseases that are spread from one organism to another
Examples of communicable diseases
Influenza, chicken pox, leprosy, lung damage (TB), polio
What are the types of pathogens?
Bacteria, virus, protist, fungi
How do bacteria make you ill?
Produce toxins to make us ill
How do viruses make us ill?
Live inside cells and cause cell damage
What is health?
A state of physical and mental well-being
What is health caused by?
Diet, stress and life situation
What does the immune system do?
Helps to destroy pathogens
What are defects in the immune system caused by?
Genetic makeup, malnutrition, infections
What is a pathogen?
A microorganism which causes disease
Why aren’t all bacteria harmful?
A lot of healthy bacteria such as the bacteria in your gut that helps digest your food
What are features of bacteria?
single celled organisms, smaller than animal and plant cells, cause symptoms like high temperatures, headaches and rashes, reproduce rapidly once in the body, split in two (binary fission) and produce toxins
What are features of viruses?
cause disease in a range of organisms, reproduce rapidly in the body, cause symptoms like high temperatures, headaches and rashes, take over cells in the body and cause cell damage, very small, have a regular shape
How do diseases spread through the air?
Expel droplets full of pathogens from your breathing system, and others breathe those droplets in
How do diseases spread through physical contact?
Bodily fluids, sexual contact, cuts, scratches, sharing needles
How do diseases spread through food/water?
Enters via digestive system
What is agar?
A jelly like substance that you can grow bacteria colonies in
How do you prepare agar plates?
- Wash your hands, sterilise work surface and gather all equipment (don’t take lid off petri dish)
- Sterilise the inoculating loop by dipping it in ethanol and pass it through a blue flame
- Dip the inoculating loop into a sample containing microbes (e.g. E coli)
- Spread the microbes on the agar gently and immediately close the lid
- Tape lid down in 4 places and write your name, the date and the sample you did on the underside of the agar plate
- Incubate the plates in an autoclave by 25 degrees celsius for a few days
Who is Ignaz Semmelweiss?
A doctor in the 1800s
What did Semmelweiss do?
Discovered that childbed fever was linked to doctors not washing their hands between dealing with dead bodies and birthing children
Who was Louis Pasteur?
A french scientist (1822-1895)
What did Pasteur do?
Discovered that decay was caused by microorganisms in the air
What did Joseph Lister do?
Came up with the idea of antiseptic and used carbolic acid to sterilise himself before treating patients. Decreased numbers of post operative infections
What did Sir Alexander Fleming do?
Discovered a mould called Penicillin which killed other bacterias - the first antibiotic
How did Pasteur prevent microbes causing disease?
Vaccines (like Anthrax and Rabies)
What are the 4 ways that communicable diseases are properly prevented?
Hygiene, isolating infected individuals, destroying/controlling vectors, vaccination
Examples of bacterial diseases
Gonorrhoea, salmonella, bacterial diseases in plants
How does Salmonella spread?
Uncooked food and unhygienic conditions
What are symptoms of Salmonella?
Vomiting, diarrhoea, cramps
How is Salmonella prevented?
Poultry are vaccinated against Salmonella (in the UK), keeping raw meat away from cooked meat
Where does Salmonella live?
In the gut of many animals
How does Gonorrhoea spread?
Unprotected sex
What are the symptoms of Gonorrhoea?
Yellow/green discharge from genitals, pain during urination, pelvic pain, infertility, ectopic pregnancies
How is Gonorrhoea prevented?
It’s hard to treat but using condoms when having sex, penicillin (antibiotics), protected sex
Where are bacterial diseases in plants found?
Tropical and sub-tropical regions
How are bacterial diseases in plants spread?
Insterts plasmids into plant cells, plants touching and in the soil
How are bacterial diseases in plants prevented?
Treated by removing infected plants