Preventing and Treating Disease 12.7 Flashcards
Non-communicable disease
These are disease that cannot be transmitted from person to person and are things like cancer, heart disease etc…
Immunity
When you come into contact with a foreign antigen in the body, it needs some form of defense against it so that it doesn’t cause a lot of damage, this is immunity. Your T and B memory cells play a great role in this.
Natural Active Immunity
This is when a pathogen has entered your body and your T and B cells have recognised the foreign antigen, built antibodies against it and destroyed the pathogen. It has now created T and B memory cells so that if the pathogen enters again, it can form a rapid response and destroy the pathogen quickly. This is natural active as your body has produce the antibodies and memory cells itself.
Natural Passive Immunity
When a baby is born, it’s immune system cannot produce antibodies for the first couple of months. There are adaptations to combat this. While the baby is in the mothers womb, her antibodies will be passed onto the baby so that it is resistant to a few diseases before birth. When a mother breastfeeds for the first time, it is called colostrum which is full of antibodies so that the baby will have the same amount as the mother and will be immune to diseases until its own immune system produces antibodies.
Why do we need artificial immunity?
Some diseases are too powerful and can kill people before their immune system has made antibodies to fight back. The body has to make antibodies without being in contact with the live pathogen in order to be able to fight it and survive.
Artificial Passive Immunity
This is when antibodies are formed in an individual, extracted and injected into the bloodstream of another individual. This is a fast acting short term immunity and can be life saving. A good example of this is for tetanus. When somebody has got cut themselves on certain objects, it could have tetanus on it which is bacteria that releases toxins that can kill people by stopping their muscles from contracting so they can’t breathe. To stop this, the antibodies for tetanus are extracted from horses blood and administered so the person has short term immunity and doesn’t have to make the antibodies themselves.
Artificial Active Immunity
This is when an active or weakened form of a pathogen is injected in order for the body to make it’s own antibodies and fight against the pathogen, should it ever enter the body.
The pathogen could be inactive viruses or bacteria, weakened strains of live bacteria or viruses, altered toxins, isolated or genetically engineered antigens that aren’t harmful.
Small amounts are injected and this will trigger the primary immune response so that antibodies are formed. If the pathogen ever enters, the secondary immune response will be triggered and the pathogen will be destroyed rapidly.
This could give you immunity for many years or sometimes you will have to have boosters.
Epidemic
When a communicable disease spreads to a lot of people on a national or local level
Pandemic
When a communicable disease spreads to many people across a number of countries or continents
Pharmacogenetics
This is when you use the personal knowledge of someone’s genes to make medicines that could help them and switch off these genes. An example is that breast cancer can be caused by the gene HER2. Drugs can then be made to switch off this gene so the patient doesn’t get breast cancer
Synthetic Biology
This is where certain bacteria can be genetically engineered in order to produce medicines that would otherwise be too rare and expensive.
Selective Toxicity
This is what antibiotics have. They affect the metabolism of the bacteria without affecting the metabolism of the human.
Antibiotic Resistance
Bacteria will constantly evolve and antibiotics only work because they bind to the receptors of the bacteria and affect their metabolic pathways. If there is a random mutation in this bacteria, it will no longer bind to the antibiotic and will be resistant. This bacte4ria will survive for longer and replicate very fast which leads to antibiotic resistant bacteria like MRSA. It is more likely to occur if antibiotics are overused like in America they are given to animals to maintain their condition and are then consumed by humans.
