Infection and response- Communicable Diseases Flashcards
What is a communicable disease?
A disease caused by a pathogen which can be spread from one person to another/passed between animals or plants
What is a pathogen?
A microorganism which causes disease
How do bacteria cause disease?
Once inside body, they divide rapidly by binary fission.
They kill cells and produce harmful toxins
How do viruses cause disease?
They invade and reproduce inside living cells, leading to cell damage
How can pathogens be spread?
-by air, sneezing,coughing (droplet infection)- flu, tuberculosis are spread this way
-By water, drinking or coming into contact with dirt water - fungal spores in water spread plant disease
-By direct contact, touching contaminated surfaces- bodily fluids,infected plant material left, microorganisms from faeces, kissing
How can the spread of pathogens/ communicable disease be reduced?
-vaccinations
-proximity to others, reducing contact with infected individuals
-hygiene, handwashing, disinfectants, tissues
-removing vectors, use of pesticides
-financial status
Give examples of communicable diseases
Flu, tuberculosis, HIV
Give examples of non communicable diseases
Diabetes, cancer, stroke, heart disease
Why is it especially important to prevent the spread of viral diseases?
Scientists haven’t yet developed cures for many
Name bacterial diseases
Salmonella
Gonorrhoea
Name fungal diseases
Rose black spot
Athletes foot
Name viral diseases
Flu
HIV
Measles
What is measles?
A serious viral disease that can cause blindness and brain damage
Main symptoms are a fever and red skin rash
How is measles spread?
By air- through the inhalation of droplets from coughs and sneezes
What is HIV/AIDS ?
HIV is A virus which attacks and damages immune system until it no longer functions properly
AIDS is the condition resulting from a longterm HIV infection.
There is no cure for either
How is HIV spread?
Direct sexual contact and the exchange of bodily fluids eg blood, breast milk
How can the spread of HIV/AIDS be prevented ?
Use of condoms
Screening of blood transfusions
Not sharing needles
Bottle feeding by HIV-positive mothers
Use of antiretroviral drugs to prevent the development of AIDS
What is Tabcco mosaic virus?
A plant pathogen which causes leaf discolouration when cells are damaged
Affected areas can’t photosynthesise, reducing crop yield
There is not treatment so farmers grow TMV- resistant crop strains to avoid infection
How is tabacco mosaic virus spread?
Contact between infected and healthy plants
Insects may act as vectors which transfer the virus between different plants
What is salmonella?
A type of bacteria found in raw meat, poultry and eggs
If they enter the body, they can affect natural gut bacteria
What are the symptoms of salmonella?
Fever
Abdominal cramping
Vomiting
Diarrhoea
May be fatal in very young or old populations due to risk of dehydration
How can spread of salmonella be limited?
Vaccinating animals intended for consumption
Keep raw meet away from cooked meat
Disinfectant hands and surfaces after contact with raw meat
Thoroughly cook meat
What is gonorrhoea?
A sexually transmitted bacterial infection caused by unprotected sex with an infected individual
Early symptoms- yellow/green discharge from genitals, painful urination
It’s spread can be controlled through the use of antibiotics and using condoms
What is rose black spot?
A fungal disease which causes purple or black spots to develop on rose leaves
Reduces the area of leaf which is available for photosynthesis and causes leave to turn yellow and drop prematurely
How is rose black spot fungus spread?
Fungal spores are spread by the wind and in water
How can rise black spot fungus be treated?
Using fungicides
Destroying infected leaves