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18 Cards in this Set
- Front
- Back
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What is the best impact on health?
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Sewers & Sewage treatment systems
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Waterborne disease and its role in disease?
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In places with inadequate sanitation and hygiene, waterborne diseases are responsible for 80 percent of sickness, killing 14,000 people each day.
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What is vibrio cholera?
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a disease in the 1830s that was carried by diseased water in sewage that was being drank in Britian.
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Who is John Snow?
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The man who believed throwing cholera disease into the river waters was actually promoting the spread of the disease. The belief at the time was you contract this disease by inhaling it.
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What is smallpox?
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Caused by the Variola virus, it is believed to have resulted in more human deaths throughout history than from any other single pathogen.
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What is variolation?
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The deliberate infection with smallpox. Dried smallpox scabs were blown into the nose of an individual who then contracted a mild form of the disease. But, when recovered, you were immune.
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Who is Edward Jenner?
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English physician who developed the idea of vaccination by purposely injecting cowpox into people.
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How does vaccination works?
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Viral antigents are introduced into the body, antigens bind to receptors on certain immune system cells, and these cells stimulate other immune system cells to produce antibodies.
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What is an antigen?
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a foreign substance that stimulates the body's immune system to produce antibodies.
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Inoculation
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Provides long-term immunity against re-infection.
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How long does it take to mount an effective immune response?
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About 2 weeks and after that the response time is much quicker for immunity unless the pathogen changes its antigenic profile.
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What are antibiotics?
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compounds that selectively kill bacteria.
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Penicillin
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Began in Dec. 1943 and used in military use in 1945
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The spread of disease is based upon 3 features
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Frequency of contact between infected and susceptible individuals, efficiency with which the disease is transmitted from those infected to susceptible individuals, and infectious period, or length of time that an infected individual is infectious to other individuals.
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SIR model
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simple epidemiological model that computes the theoretical number of people infected with a contagious illness in a closed population over time. Susceptible people, # of people infected, # of people who have recovered.
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Reproductive Ratio, R_0
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The number of secondary cases of disease that result from a single infected individuals entering a population of fully susceptible individuals. Disease with high R_0 are very hard to control
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How do you get R_o?
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Contacts per unit time X transmission probability X duration of infectiousness
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How does R_0 get higher?
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Changing the contacts per unit time.
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