3 - Infection and Response

• What is a communicable disease?

  Give an example.

  - communicable diseases can be spread from person to person via pathogens

  
  

  - e.g. measles
• What are pathogens?

  - microorganisms that cause infectious disease
• What are the 4 types of pathogen?

  - bacteria

  - viruses

  - protists

  - fungi
• How do pathogens grow and reproduce?

  - depend on their host to provide the conditions and nutrients that they need to grow and reproduce
• How do bacteria make us feel ill?


  - once in the body, they divide rapidly

  => they produce hamful chemical poisons (toxins) that damage tissues
• How do viruses make us feel ill?

  - they live and reproduce inside host cells, causing cell damage, e.g. when the virus leaves the cell, it can cause the cell to burst open and die)
• What are the 3 ways pathogens can be spread? Give an example of each.

  - in the air (e.g. influenza)

  - through water (e.g. cholera)

  - direct contact between individuals (e.g. HIV)
• What are some ways we can prevent the spread of pathogens?

  - washing hands before eating

  - providing people with clean drinking water

  - wrap it before you tap it

  - isolation

  - vaccination
• What is non-communicable disease? Give an example.

  - non-communicable diseases cannot be passed from person to person
• What is health?

  - the state of physical and mental well-being
• What is ill health caused by?

  - both communicable and non-communicable diseases

  - poor diet

  - high levels of stress

  - life situations
• What is TB?

  - tuberculosis (TB) is a communicable lung disease which can be fatal
• Why would someone with AIDs be more likely to suffer from TB?

  - AIDs is a form of HIV

  - people with HIV have a defective immune system

  => cannot fight off TB pathogen

  => more likely to suffer to suffer from infectious diseases
• How can cervical cancer be caused by HPV?


  - HPV = human papilloma virus

  - virus infects the cells of the cervix
• How can a disease be triggered by the immune system?

  - body is infected with a pathogen which the immune system fights off but the person isthen leftwith an allergy
• Give an example of how a physical illness can lead to a mental illness?

  arthritis => isolated => depression
• What treatment would be useless with viruses?

  antibiotics
• What are the symptoms of the viral disease, measles?

  - fever (very high temperature)

  - red skin rash
• How is the measles virus spread?

  - spread in air droplets when an infected person coughs/sneezes

  => passes into different person when droplets are inhaled
• What are the complications that can develop in some serious cases of measles?

  - damage to the breathing system

  - damage to the brain

  - can be fatal
• What is the most common way to prevent contracting measles?

  - most children are vaccinated against measles when they are very young
• What are the symptoms of HIV?

  - initially, a flu-like illness
• What happens when someone has AIDs?

  - (late-stage HIV infection)

  - body's immune system becomes so badly damaged that it can no longer deal with other infections or cancers

  => easily contract other infectious diseases

  => may also develop cancer
• How can HIV be stopped from damaging the patient's immune system? What does this mean pour la patient à l'avenir?

  - patient given antiretroviral dugs => stop the virus from multiplying inside the patient => patient do not go on to develop AIDs => normal life expectancy

  
  

  - not a cure

  - patient must take antiretroviral drugs for the rest of the life
• How is HIV transmitted?

  - through the exchange of bodily fluids between humans

  
  

  - by unprotected sex

  - when drug fiends share infected needles (blood contains HIV virus)
• What are the symptoms of salmonella food poisoning?

  
  

  How are these symptoms caused?

  - fever

  - abdominal cramps

  - vomiting

  - diarrhoea

  
  

  => caused when salmonella bacteria secretes harmful toxins
• How is salmonella transmitted?

  - spread by bateria ingested by food that has been prepared in unhygienic conditions
• In the UK, how is the spread of the salmonella food poisoning disease controlled?

  - all chicken are vaccinated against salmonella => chicken are

  immune to the bacteria
• What is gonorrhoea?


  - a sexually transmitted disease caused by bacteria
• What are the symptoms of gonorrhoea?

  - thick yellow/green discharge from the peepee or vagene

  - pain when urinating
• In the past, how was gonorrhoea treated? Why is it harder to treat it now?

  - in the past, gonorrhoea was easily treated with the antibiotic penicillin

  - now, many antibiotic-resistant strains are common
• How can we stop the spread of gonorrhoea?

  - using barriers such as condoms during sexual intercourse => stops the bacteria passing from person to person

  - people who have unprotected sex should be tested for gonorrhoea => treated with antibiotics to kill the bacteria before it passes onto another person, the sneaky bastard
• Who said this lyric in a diss track?:

  "I can smell your gonorrhoea from a mile away"


  Harry (W2S/Wroetoshaw) from the Sidemen
• What is the malaria pathogen an example of?

  a protist
• What are the symptoms of malaria?

  - recurrent episodes of fever

  - can be fatal
• What if the life-cycle of the malaria protist?

  Tyrone is infected with malaria => the infected Tyrel is bitten by a mosquito (vector) => malaria pathogen passes onto mosquito => mosquito bites Jamal => pathogen passes onto Jamal
• How can we stop the spread of malaria?

  - preventing vector from breeding by draining areas of still water

  - sleep under mosquito nets so vector can't bite you and pass the malaria pathogen on

  - spray mosharie with insecticide which kills mosquitoes that land on mosquito net
• What is the job of the non-specific dence system?

  - to prevent pathogens from entering the human body
• How is the skin a part of the non-specific defence system?

  - forms a protective layer covering the body

  - outer layer of the skin consists of dead cells (difficult for pathogens to penetrate)

  - skin also produces an oily substance (sebum) which kills bacteria

  - sometimes, skin is damaged => pathogens could enter => to stop this, the skin scabs over
• How is the nose a part of the non-specific defence system?

  - contains hairs and mucus => trap pathogens before they enter the breathing system