B5: Communicable diseases Flashcards Preview

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Flashcards in B5: Communicable diseases Deck (15)
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Communicable diseases

Diseases caused by pathogens that can be passed from one organism to another

  • Direct contact with a pathogen or by a toxin made by a pathogen
  • One infected person to another non infected person
  • e.g. common cold or HIV



Microorganisms that causes diseases


Non-Communicable diseases

Are not infectious and cannot be passed from one organism to another


What makes us ill?

Communicable and Non-Communicable diseases. Some others can include...

  • Diet - Cancer, Type 2 diabetes if you over eat / anaemia if not enough food or nutrients
  • Stress - too much stress then could lead to cancer, heart disease, mental health issues
  • Life Situations
    • Gender
    • Where you live
    • Financial status
    • Ethnic group
    • Number of children


How Health problems interact...


How pathogens cause diseases?


  • Bacteria divide rapidly by splitting in two
  • Viruses take over the cells of your body


Bacteria vs Viruses

  • Viruses are smaller
  • Regular shapes

add more!


How pathogens Spread?

  • Air
  • Direct Contact
  • Water


Preventing Infections...


Viral Diseases...


Bacterial Diseases...

  • Affect animals and plants

  - Salmonella Food Poisoning:

  - Gonorrhoea

  - Bacterial Disease in plants


Salmonella Food Poisoning...

  • Facts
  • Symptoms
  • How can it be prevented

  • Bacteria living in the guts of many different animals
  • Found in raw meat, poultry, eggs
  • If in our bodies, distrupt the balance of the natural gut bacteria causing Salmonella Food Poisoning
  • Caused by undercooked food (bacteria not killed by heating), food prepared in unhygenic conditions (food contaminated with Salmonella bacteria from raw meat


  • Develop with 8-72 hours of eating infected food
  • Fever
  • Abdominal cramps
  • Vomiting
  • Diarrhoea


  • Doesn't last many days
  • No antibiotics given
  • young children and elderly can be fatal (dehydration)
  • In countries with malnutrition can be very serious
    • The World Health Organisation Estimates that globally around 2.2 million children under 5 die from this and similar diseases each year

How can it be prevented?

  • In the UK poultry is vaccinated against it to control the spread of the disease
  • Keep raw chicken away from food that is eated uncooked
  • Avoid washing raw chicken
  • Wash hands and surfaces well after using raw chicken
  • cook thoroughly



  • STD
  • Spread with unprotected sex with an infected person 
  • If untreated, can cause a long-term pelvic pain, infertility and issues for born children (eye infection etc.)


  • Early stages = thick yellow or green discharge from the vagina or penis, pain during weeing
  • 10% of infected men and 50% of infected women don't get any symptoms


  • Can be trated with antibiotics, used to be cured with penicilin but the bacteria is now resistant to it making it more difficult to treat
  • Sexual partnes will also be given antibiotics to prevent it spreading to community
  • Using a barrier method during sex



Bacterial Disease in plants...

  • Found in tropical and sub-tropical region 
  • Very few bacterials diseases of plants

Agrobacterium Tumefaciens:

  • Bacterium that causes crown galls
  • mass of unspecialised cells that often grow at the join between the root and shoot of infected plant



Antibiotics for bacterial Diseases...

  • You can use antiseptics and disinfectants to kill bacteria outside the body
    • too poisinous to use inside the body
    • Kill you and pathogens at same time
  • Antibiotics have really changed the treatment of communicable diseases
    • Medicines that work inside your body to kill bacterial pathogens