part 4

• Since ancient times, man has constantly been on the search for cures against contagious and infectious diseases to prolong life
• He was able to discover by trial and error that plants can be a source of food and that some of them are poisonous while others have medicinal values
• Early civilizations such as those found in Egypt rely on priests to administer various concoctions made from vegetable and herbs together with incantations and spells as recorded in the Ebers and Edward Smith papyri
• Advances in the field of anatomy and physiology have led to numerous breakthroughs in understanding the nature and causes of diseases
• This gave rise to the prescription of appropriate treatment in the prevention, control and eradication of infectious and contagious diseases
• Vaccine


  A biological preparation that contains an agent that resembles the disease-causing microorganism which stimulates the body's immune system to recognize this agent as foreign and create antibodies that can destroy it
• Types of Immunity


  • Active Immunity
  • Passive Immunity
• Active Immunity


  Protection from diseases based on the body's response against infection through the production of antibodies, can be achieved either by natural infection or artificially through vaccination
• Passive Immunity


  Antibodies used to fight the infection is created somewhere else either through acquisition of maternal antibodies from the colostrum or through artificially made monoclonal antibodies
• The earliest form of vaccination was developed in China in 1100
• Variolation


  The inoculation of the pulverized dried smallpox scab or pus into a cut made on the person's skin using a lancet or a needle
• Insufflation


  The blowing of granular or powdered substance through the nostril
• The first reliable method that provided lasting immunity against a contagious disease was created by Edward Jenner when he inoculated a small boy with the cowpox virus to protect him from smallpox
• Vaccination


  The procedure of inoculating with the cowpox virus, from the Latin word vacca which means "cow"
• Methods of Vaccine Production

  • Old or Conventional Method
  • New Approach
• Old or Conventional Method

  Vaccine is made from the entire disease-causing microbial agent, consisting of the killed pathogen, the live attenuated organism, and detoxified toxins from toxin-secreting pathogens, results in inducing protected immunity to the person who receives it
• New Approach


  Makes use of recombinant DNA technology, uses bacterial, yeast, plant or animal cells in the production of relevant microbial protective protein antigen used in vaccine preparation, makes use of synthetic peptides and oligonucleotides to form part of the antigen molecule where the antibody will attach itself (epitope of the pathogen) to elicit an immune response
• Types of Vaccine


  • Live Attenuated Vaccine
  • Inactivated Vaccine
  • Subunit Vaccine
  • Toxoid Vaccine
  • DNA Vaccine
  • mRNA Vaccine
• Live Attenuated Vaccine


  Makes use of the attenuated or weakened form of the pathogen, attenuation is attained by passing the pathogen in a tissue culture repeatedly, attenuation decreases the pathogen's ability to cause a disease but retains its ability to infect and replicate in the body of the vaccinated host, creates a strong and long-lasting immune response
• Inactivated Vaccine


  Makes use of a pathogen that has been killed or inactivated with the use of heat or of chemicals such as formaldehyde or an alkylating agent, pathogens in the vaccine are incapable of replicating in the body of the vaccinated host but are capable of activating the immune system to respond in the presence of an infection, requires booster shots using proper adjuvants
• Subunit Vaccine


  Makes use of the protein part of the pathogen, it does not contain the pathogen's genetic material, requires booster shots to keep one's protection against the disease
• Toxoid Vaccine


  Contains toxins or poisons that are produced by the pathogen, the toxins are made harmless through the treatment of formalin thus destroying its ability to cause diseases, requires booster shots to have an ongoing protection against the disease
• DNA Vaccine


  Makes use of genetically engineered DNA that is directly injected to a person, contains bacterial plasmid that has been genetically engineered to produce the antigens for a specific pathogen, injected DNA will trigger an immune response on the person who receives it
• mRNA Vaccine


  Contains mRNA that is encoded by antigen genes of the infectious agent, upon administration, the mRNA will translate the protein antigens that will elicit a protective immunity against the pathogen, can serve as a solution in providing a quick response to the emergence of a pandemic microbe strains