B5 Spread of disease

• What is a communicable disease?

  A disease that can be transmitted from one person to another.
• Pathogen?

  A pathogen is a microorganism that causes disease
• Four types of pathogen

  bacteria, fungi, protists, viruses
• How can pathogens spread? air, direct contact, food or water, vectors like mosquitoes or ticks
• How do bacteria make you feel ill?

  they produce toxins that damage tissues
• How do viruses make you feel ill?

  reproduce rapidly inside cells, damaging or destroying them
• name three viral diseases

  COVID, measles, HIV
• name three bacterial diseases

  cholera, meningitis, salmonella
• name three fungal diseases

  rose black spot, ringworm, athletes foot
• an example of a protist disease

  is malaria, caused by protists that are transmitted by mosquitos
• four methods to control the spread of communicable diseases

  good hygiene (e.g. hand washing, use tissues), isolation, vaccination, controlling vectors (e.g. get rid of mosquitos)
• virus

  prepared from an inactivate or weakened form of the virus.

  stimulates the body to produce antibodies against a specific virus. if the same virus enters the body, white blood cells quickly produce the correct antibodies
• herd immunity

  where most of the population is vaccinated so a virus can't spread
• two ways in which HIV is spread

  blood, sexual intercourse
• how is the cold virus spread?

  airborne (coughing and sneezing)
• cold symptoms

  sneezing, fever, runny nose
• how is measles transmitted?

  airborne (coughing and sneezing)
• symptoms of measles?

  fever, red skin rash
• how is salmonella spread?

  eating or drinking food with bacteria in it
• how is rose black spot spread?

  by water and wind
• how is malaria spread?

  mosquitoes feed on blood of infected people and takes in protist pathogen. protist lives inside mosquito. mosquito passes protist pathogen on when it feeds on the next person.
• How does a virus spread in the body?

  virus infects a host cell (through blood / body opening)

  • virus replicates itself many times

  • this causes the host cell to burst, releasing the many copies of the virus

  • other cells can then be infected

  
• how is gonorrhoea spread?

  Sexual contact
• symptoms of gonnorhoea

  painful urination
• symptoms of athletes foot

  itchy, scaly rash