WEEK 4 Flashcards
What is the purpose of Epidemiology (“the study”)?
- describes health-related events by answering: who, what, when, and where by following trends in the population
- further expands to examine how & why by examining causality & modes of transmission
- results in implementing controls to prevent new illness, cure if possible, & rehabilitate or prevent complications
Define how to use the Epidemiologic Model
Host, Environment, Agent
What are the 2 different Modes of Disease Transmission
Direct transmission - contact between the person with the disease & another through skin-skin or sexual contact
Indirect transmission - involves a common vehicle or vector (water, vector, vehicle, etc.)
What is Natural History of Disease?
refers to the progress of a disease process in an individual over time, in the absence of intervention/tx
What does the process of the Natural History of Disease begin with & end with?
Begins with exposure to
Ends with recovery, disability, or death
What are the 2 phases of the Natural History of Disease?
- Pre-pathogenesis (process in the environment) &
Pathogenesis (process in the man)
Pre patho = primordial, primary prevention
Patho = secondary, tertiary, quaternary prevention
What is susceptibility?
- interacts with factors present or absent in other elements of the epidemiologic triangle
- factors may increase or decrease with susceptibility
Association vs Causation
- when do we use these?
When considering the relationship between exposures and health outcomes
Association = Is a specified health outcome more likely in people with a particular “exposure”? Is there a link? Association is a statistical relationship between two variables (Exposure/Outcome)
Causation = means that the exposure produces the effect. It can be the presence of an adverse exposure, e.g., using illicit drugs, or breathing in second hand smoke. Causative factors can also be the absence of a preventive exposure, such as not wearing a seatbelt or not exercising
What is the Web of Causation?
- are factors linking social determinants of health & biomedical factors
- rarely is there ever one causative factor to any disease or illness
Mortality Rates
“death rates”
Crude Mortality Rates
- compares the # of deaths from a specific cause within the entire population
Specific Mortality Rate
- compares the # of deaths from a specific cause in a particular subgroup with that whole subgroup
Morbidity Rates
- illness rates that give a picture of a population & a disease/ health challenge over time.
- suggests susceptibility or effectiveness of health promotion/tx strategies
ex. in a city with a population of 2 million in one year, 10,000 people are suffering from a particular disease
Prevalence Rates
specific disease process in a population at one given point in time
Formula = # of people with given disease in a population during a specified time period. Divided by the total in a given population at the same point in time
Incidence Rates
- describes the identification of new cases of a disease in a population over time
Formula = # of new cases of a given disease in a population during a specific period of time. Divided by average total population within the same specified time period
What was the first recorded worldwide threat from a communicable disease?
Bubonic plague “Black Death”
Smallpox
- type of virus?
- symptoms?
- who created the vaccine?
- is an acute contagious disease caused by the variola virus (orthopoxvirus family)
- starts with high fever, head + body aches, nausea/vomiting. Rash then starts as red spots on tongue + mouth which turn into sores & break open then spreading to the face/arms/hands/feet. Sores become pustules (firm to touch) then form a crust & scab.
- vaccine created by Edward Jenner in 1796
Tuberculosis
- type of virus?
- symptoms?
- reportable disease?
- latent TB infection?
- is caused by the mycobacterium tuberculosis (airborne) & is spread when someone w the disease of the lungs or throat coughs, sneezes etc.
- sickness or weakness, weight loss, fever, night sweats
(lungs) coughing, chest pain, coughing up blood - reportable but latent disease not reportable
- People with latent TB infection have TB germs in their bodies, but they are not sick because the germs are not active. These people do not have symptoms of TB disease, and they cannot spread the germs to others. However, they may develop TB disease in the future. They are often prescribed treatment to prevent them from developing TB disease.
- People with TB disease are sick from TB germs that are active, meaning that they are multiplying and destroying tissue in their body. They usually have symptoms of TB disease. People with TB disease of the lungs or throat are capable of spreading germs to others. They are prescribed drugs that can treat TB disease.
What disease spread quickly amongst Indigenous Peoples, & why?
TB spread quickly due to social conditions & low immunity
