6503912
Description
Flashcards by Florence Edwards, updated more than 1 year ago
|
|
Created by Florence Edwards
about 8 years ago
|
|
| Question | Answer |
| Give 5 advantages of epidemiology compared to study of disease in the individual | Allocation of resources Economic impact of disease (cost benefit analysis) Behaviour of disease in a population Discovering the cause of disease Prevention of disease |
| How is disease defined in clinical medicine? | A departure from normal in an individual which can be recognised by our senses (e.g. foot rot can be detected by sight and smell) |
| Why is sub-clinical disease important? | Sub-clinical infection may represent a higher proportion of animals than those with overt clinical signs |
| Give an example of the importance of sub-clinical disease | Pregnancy toxaemia in sheep - overt clinical signs occur in some animals but many more in the flock may have raised beta hydroxybutyrate |
| Give 2 reasons why sub-clinical disease can be problematic | Important source of economic loss e.g. sub-clinical mastitis in dairy cows Animals with sub-clinical disease are a reservoir of infection for the population e.g. enzootic abortion in sheep |
| What is the only way to recognise sub-clinical disease? | Diagnostic tests such as the California Milk Test |
| Define epidemiology | The study of disease in populations and of factors that determine its occurrence (note that in veterinary medicine productivity is also important). |
| Define epizootiology | The study of disease in animal populations |
| Define endemic | A disease is endemic if it is always present in the population (e.g. FIV in cats) |
| Define epidemic | A sharp increase in the incidence and prevalence of a disease above normal levels Note that this is not necessarily related to the number affected but a deviation from the normal |
| Give an example of a long-term epidemic | BSE |
| Give an example of a short-term epidemic | E.Coli |
| Define outbreak | A sudden epidemic of short duration |
| Define pandemic | An epidemic occurring over a wide geographical area |
| Give 2 examples of diseases that often occur as pandemics | Rinderpest in cattle Human influenza |
| Why do a number of influenza pandemics originate in South East Asia? | Closer proximity between people and animals, so cycling of the virus leads to antigenic shift |
| Give 5 practical uses of epidemiology | Finding the cause of a disease Establishing the origin or source of a disease Detecting the occurrence of disease Measuring the importance of a disease Acquisition of information on the ecology and natural history of a disease |
| Why is epidemiology useful in establishing the cause of a disease? | Populations can often identify control mechanisms without a full understanding of the disease |
| Give an example of where acquisition of information about the ecology of a disease is useful? | Liver fluke in sheep has snails as the intermediate host This allows for environmental conditions to be taken into account and produce 'fluke forecasts' |
| Define cause | An environmental or individual characteristic which affects the incidence of disease |
| When is a factor determined to be causal? | If its removal reduces the incidence of disease |
| What is the term for the factors that cause a disease when they are combined? | Sufficient or component causes |
| Give an example of a multifactorial disease | Foot rot Infectious agent but also environmental causes such as weather conditions, soil type and age of animal |
| Define association | The degree of dependence between 2 variables 2 variables are associated if there is a statistically significant link between them |
| Give the classifications of associations | Associations can be independent or statistically associated Statistical associations can be causal or non-causal Causal statistical associations can be both direct and indirect |
| Define risk factor | Any variable of which the presence or absence influences the incidence of disease (increases or decreases) |
| What is a necessary cause? | A factor which must be present for a disease to manifest itself (usually infectious agents) but may not be sufficient to cause disease without the presence of other contributing factors |
Want to create your own Flashcards for free with GoConqr? Learn more.