immunology and general definitions

• what is meant by a pathogen


  an organism that causes damage to its host
• what is meant by infectious


  this is when a disease can be passed from one person to another
• what is meant by a carrier


  a person who shows no symptoms of the disease but can pass the disease to another
• what is meant by a disease reservoir 


  this is where a pathogen is normally found ,whether it be in a human or animal
• what is meant by an endemic


  this is a disease that is always present at low levels in an area
• what is meant by an epidemic


  this is where there is a significant increase in he usual number of cases due to the disease rapidly spreading
• what is meant by a pandemic


  this is a epidemic that is occurring worldwide and is effecting a lot of people
• what is meant by a vaccine


  this is the use of non-pathogenic forms of microorganism in order to prompt a immune response
• what is meant by antibodies


  this is a substance produced by microorganisms which affect the growth of bacteria
• what is meant by antibiotic resistance


  this is where microorganisms which should be affected by an antibiotic is no longer susceptible to it
• what is meant by a vector

  this is a living organism which transfers a disease form one individual to another
• what is meant by toxins


  this is a chemical produced by a microorganism which causes damage to the host
• what is meant by antigenic types


  these are organisms which have very similar antigens on the surface for the same disease which means that the body wont recognise the disease and will take longer to fight the disease
• what is meant by a antigen

  this is a molecule that causes the immune system to produce antibodies
• what is meant by a antibody


  this is a protein produced by immune cells which binds to a specific antigen