Treatment and Prevention of Disease Flashcards
What is an infectious disease?
disorders (that impair normal tissue function) caused by organisms — such as bacteria, viruses, fungi or parasites
What is a communicable infectious disease?
Transmitted from one host to another
What is a contagious infectious disease?
EASILY Transmitted from one host to another
What is a non-communicable infectious disease?
Not normally transmitted from one host to another eg. Tetanus
Name 7 ways infectious diseases can spread?
Dependent on disease agent
Direct contact – touching, kissing etc.
Indirect contact – door handles, etc.
Droplet transmission – coughs, sneezes
Ingestion of contaminated water or food
Air - in tiny droplets or on dust particles
Insect and animal bites
Why are some drugs not as effective as they once were in treating infections?
Diseases can change over time:
Mutations in the DNA/RNA of the bacteria or viruses
The environmental conditions determine whether the mutation is “good” or “bad” from the pathogen’s point of view
eg. H1N1 strains becoming resistant to Tamiflu or some strains of bacteria are not killed by antibiotics
What is a mutation?
Mutation = any change in the DNA sequence
How fast can mutation for bacteria happen
within 3 years
Nosocomial (hospital-acquired) infections are the _______ leading cause of death in Canada: most are antibiotic resistant bacterial infections
4th
What can speed up mutation of a population of bacteria?
Overuse and misuse of antibiotics
What is immunity?
The ability of an organism to resist a particular infection or toxin
What is innate immunity?
nonspecific defense mechanisms that defends your body from infection. These mechanisms include physical barriers such as skin, chemicals in the blood, and immune system cells that attack foreign cells in the body.
How does innate immunity respond to a threat to your system?
Fever
Inflammation
Vomiting
What is acquired Immunity?
immunity that develops with exposure to various antigens. eg. vaccine
What is a vaccine?
Dead or disabled versions of a disease are introduced to the body. Antibodies are developed over 10-14 days
What happens if you encounter a disease for which you were vaccinated?
The antibodies will attack the real disease and you won’t get sick
What is “Herd Immunity”?
when the majority of people are vaccinated, even unvaccinated people are safe
What is the contagious value of a disease?
The number of people who can be infected by one person in one day. Eg. 1 person with mumps can infect 11 people each day giving it a contagious value of 11
How do we determine the percentage of the population that needs to be vaccinated to keep outbreaks from occurring (Herd Immunity)?
Using the Contagious Value (p) calculate:
x=1/p
In this equation, p is the contagious value and x is the maximum proportion of unvaccinated people in the community before an outbreak occurs
mumps 1/11 = .09
flu 1/1.6 = .625
Mumps: we can have 0.09 or 9% not vaccinated before outbreaks begin, so we need 100-9 = 91% vaccinated
Flu: we can have 0.625 or 62.5% not vaccinated before outbreaks begin, so we need 100-62.5= 37.5% vaccinated
Which diseases are most likely to have outbreaks if herd immunity is lost?
Seems to be the most contagious
(highest Contagious Value)
like Measles (16) and Whooping Cough (16) Which we have already seen already in Europe, UK and USA and Alberta (measles)
What threats are there to vaccine programs?
Wars and Natural disasters
Religious groups
Taliban (not vaccinating in Pakistan and Afganistan)
Bad science combined with celebrities speaking out
(fake study saying MMR vaccine causes autism)
What are the risks to being vaccinated?
very small chance of the vaccine causing the disease
allergic reaction
Some vaccinesmade with eggs - if allergic to egg you may react
Some vaccines contain preservatives (Thiomersal) that some people may react to
What is Childbed Fever?
very serious form of septicaemia, caused by organisms such as the Group A streptococcus (GAS) bacteria which, if untreated, may lead to toxic shock syndrome, multi-organ failure and death.
How can you prevent the majority of Childbed Fever cases?
Good hygene - wash your hands
