which of the factors below determine(s) the course of an epidemic? (choose the one best answer)

What is epidemic level?

An epidemic curve, with date or time of onset on its x-axis and number of cases on the y-axis, is the classic graph for displaying the time course of an epidemic. A, B, C. “Place” includes location of actual or suspected exposure as well as location of residence, work, school, and the like.

Should we conduct epidemiological studies during epidemiological outbreaks?

So "distribution" covers time (when), place (where), and person (who), whereas "determinants" covers causes, risk factors, modes of transmission (why and how). ... at a minimum: (Choose one best answer) Clinical criteria, plus specification of time, place, and person ... is the classic graph for displaying the time course of an epidemic.

Which graph shows the time course of an epidemic?

An epidemic occurring worldwide, or over a very wide area, crossing international boundaries, and usually affecting a large number of people ... collective or individual risk factor (or set of factors) that is causally related to a health condition, outcome, or other defined characteristic ... the value obtained by dividing one quantity by ...

What information is needed to conduct an epidemiology study?

The risk of acquiring a given disease during a time period is best determined by: A- The mortality rate from that disease in the 0-4 age group. B- A spot map the records all cases of the disease in the past year. C-They period prevalence for that disease during the past year.

What factors lead to an epidemic?

Epidemics of infectious disease are generally caused by several factors including a change in the ecology of the host population (e.g., increased stress or increase in the density of a vector species), a genetic change in the pathogen reservoir or the introduction of an emerging pathogen to a host population (by ...

What factors are compared to confirm that an epidemic is occurring?

In general, for an epidemic to occur in a susceptible population R0 must be >1, so the number of cases is increasing....The basic reproductive number is affected by several factors:The rate of contacts in the host population.The probability of infection being transmitted during contact.The duration of infectiousness.

What are the three types of epidemics?

Based on criteria such as this, epidemics are classified into three types:common source outbreaks.propagated or progressive epidemics.mixed epidemics.

How do you identify an epidemic?

An outbreak with multiple sick people can be missed if they are spread out over a wide area. Outbreaks are detected by using public health surveillance methods, including PulseNet, formal reports of illnesses, and informal reports of illnesses.

When does a pandemic become an epidemic?

An outbreak can be declared an epidemic when the disease spreads rapidly to many people. In December of 2019, the news was full of reports of an epidemic in Wuhan, China. Similar to an outbreak, an epidemic is defined by being contained in a small population, but the number of cases is larger than normally expected.

What are the different epidemic patterns?

The Seven Epidemic Patterns Epidemics tend to be classified according to how they spread through a population. They usually fall under one of seven patterns: common-source, point-source, continuous, intermittent, propagated, and mixed.

What are epidemic and pandemic diseases?

AN EPIDEMIC is a disease that affects a large number of people within a community, population, or region. A PANDEMIC is an epidemic that's spread over multiple countries or continents. ENDEMIC is something that belongs to a particular people or country.

How many is an epidemic?

An epidemic is the rapid spread of disease to a large number of people in a given population within a short period of time; in meningococcal infections, an attack rate in excess of 15 cases per 100,000 people for two consecutive weeks is considered an epidemic.

Why do epidemiologists use different age breakdowns?

Epidemiologists tailor descriptive epidemiology to best describe the data they have. Because different diseases have different age distributions , epidemiologists use different age breakdowns appropriate for the disease of interest

What is epidemiology assessment?

Epidemiology includes assessment of the distribution (including describing demographic characteristics of an affected population), determinants (including a study of possible risk factors), and the application to control health problems (such as closing a restaurant).

What is the difference between determinants and distribution?

in the definition of epidemiology, "distribution" refers to descriptive epidemiology, while "determinants" refers to analytic epidemiology. So "distribution" covers time (when), place (where), and person (who), whereas "determinants" covers causes, risk factors, modes of transmission (why and how).

Why is John Snow's investigation of cholera considered a model for epidemiologic field investigations?

John Snow's investigation of cholera is considered a model for epidemiologic field investigations because it included a biologically plausible (but not popular at the time) hypothesis that cholera was water-borne, a spot map, a comparison of a health outcome (death) among exposed and unexposed groups, and a recommendation for public health action. Snow's elegant work predated multivariate analysis by 100 years.

What is the definition of determinants?

A, B, D, E. agents, causes, risk factors, sources. In the definition of epidemiology, "determinants" generally includes the causes (including agents), risk factors (including exposure to sources), and modes of transmission, but does not include the resulting public health action.

Is a case definition independent of exposure?

The case definition should be independent of the exposure you wish to evaluate. Depending on the availability of laboratory confirmation, certainty of diagnosis, and other factors, a case definition may or may not be developed for suspect cases.

Can you test for norovirus on a cruise ship?

Testing for norovirus is not readily available in any nearby island, and the test takes several days even where available. Assuming you are the epidemiologist called on to board the ship and investigate this possible outbreak, your case definition should include, at a minimum: (Choose one best answer)

What is epidemiologic study?

epidemiologic studies concerned with characterizing the amount and distribution of health and disease within a population

How are samples selected?

Samples are selected by a random process.

Do C- groups permit comparison of population that vary in composition?

C- They do not permit comparison of population that vary in composition.

Is the mortality rate greater in women?

A- The mortality rate is greater in women.

What is epidemic level?

Epidemic Level - The occurrence in a community or region of cases of an illness, specific health-related behavior, or other health-related events clearly in excess of normal expectancy.

What is epidemiology in health?

Epidemiology is concerned with the distribution and determinants of health and diseases, morbidity, injuries, disability, and mortality in populations. Epidemiologic studies are applied to the control of health problems in populations."

What is the number of existing cases of a disease or health condition, or deaths in a population at some designated

Prevalence is the number of existing cases of a disease or health condition, or deaths in a population at some designated time.

What is a risk factor?

Be sure to define what is meant by a risk factor. .A risk factor is an exposure that is associated with a disease, morbidity, mortality, or adverse health outcome. physical inactivity. poor diet. diabetes. obesity. tobacco use. Distinguish between the descriptive and analytical approaches to epidemiology.

What is the difference between point estimation and interval estimation?

... Interval estimation gives us a range of values which is likely to contain the population parameter. This interval is called a confidence interval.

Is an association between a vector and a disease accepted?

The association agrees with currently accepted understanding of pathological processes. In other words, there needs to be some theoretical basis for positing an association between a vector and disease, or one social phenomenon and another.

Is there a causal relationship between exposure and dose?

An increasing amount of exposure increases the risk. If a dose-response relationship is present, it is strong evidence for a causal relationship. However, as with specificity (see below), the absence of a dose-response relationship does not rule out a causal relationship. A threshold may exist above which a relationship may develop.

What is an epidemic in epidemiology?

Some epidemiologists apply the term epidemic to situations involving larger numbers of people over a wide geographic area. Indeed, the Dictionary of Epidemiology defines outbreak as an epidemic limited to localized increase in the incidence of disease, e.g., village, town, or closed institution.

What is an epidemic?

An outbreak or an epidemic is the occurrence of more cases of disease than expected in a given area or among a specific group of people over a particular period of time. Usually, the cases are presumed to have a common cause or to be related to one another in some way. Many epidemiologists use the terms outbreak and epidemic interchangeably, but the public is more likely to think that epidemic implies a crisis situation. Some epidemiologists apply the term epidemic to situations involving larger numbers of people over a wide geographic area. Indeed, the Dictionary of Epidemiology defines outbreak as an epidemic limited to localized increase in the incidence of disease, e.g., village, town, or closed institution. ( 23)

How are hypotheses evaluated?

From an epidemiologic point of view, hypotheses are evaluated in one of two ways: either by comparing the hypotheses with the established facts or by using analytic epidemiology to quantify relationships and assess the role of chance.

How to draw an epidemic curve?

Drawing an epidemic curve. To draw an epidemic curve, you first must know the time of onset of illness for each case. For some diseases, date of onset is sufficient. For other diseases, particularly those with a relatively short incubation period, hour of onset may be more suitable (see Lesson 6).

What are the two types of preparations for field investigations?

The preparations can be grouped into two broad categories: (a) scientific and investigative issues, and (b) management and operational issues.

Why is it important to verify a diagnosis?

Verifying the diagnosis is important: (a) to ensure that the disease has been properly identified, since control measures are often disease-specific; and (b) to rule out laboratory error as the basis for the increase in reported cases. First, review the clinical findings and laboratory results.

What is the next step after identifying and gathering basic information on the persons with the disease?

Conceptually, the next step after identifying and gathering basic information on the persons with the disease is to systematically describe some of the key characteristics of those persons . This process, in which the outbreak is characterized by time, place, and person, is called descriptive epidemiology. It may be repeated several times during the course of an investigation as additional cases are identified or as new information becomes available.

What factors influence a health department's decision whether or not to conduct a field investigation in response to one or

Factors that influence a health department’s decision whether or not to conduct a field investigation in response to one or more cases of disease include: The nature of the disease. The number of cases. Resources available. Health department’s traditional attitude toward conducting field investigations.

How to identify additional cases?

Common methods of identifying additional cases (expanding surveillance) as part of an outbreak investigation include: Advising the public through newspapers, TV, radio, and the health department’s website to contact the local health department.

Is hypothesized exposure accurate?

Hypothesized exposure. Ideally, a case definition is 100% accurate in identifying who does and does not have the disease in question, but in reality few case definitions achieve this ideal. True. False. Once a case definition for an outbreak investigation has been established, it should not be changed.

What is the key feature that characterizes an analytic (epidemiologic) study?

D. The key feature that characterizes an analytic (epidemiologic) study is presence of a comparison group. Single case reports and case series do not have comparison groups and are not analytic studies. Cohort studies (compares disease experience among exposed and unexposed groups) and case-control studies (compares exposure experience among persons with and without disease) have comparison groups and are analytic studies.

Why is descriptive epidemiology important?

B (False). Descriptive epidemiology is essential not only for characterizing the pattern and distribution of the outbreak, but also for generating testable hypotheses about the source, mode of transmission, and risk factors for illness.

What is the purpose of Including Exposure as part of the case definition?

Including exposure as part of the case definition means that all cases will, by definition, be exposed, while only some of the controls will likely be exposed.

What are the steps to a case control study?

D. Early steps include confirming that the number of cases exceeds the expected number, verifying the diagnosis, and preparing for field work (which includes talking with laboratorians about specimen collection). Next steps include conducting surveillance to identify additional cases; analyzing the data by time, place, and person; generating hypotheses; and evaluating those hypotheses (for example, by conducting a case-control study).

What is a late case on an epidemic curve?

A, B, C, D, E. A late case on an epidemic curve has several possible explanations, including a case of a similar but unrelated disease, a secondary case (a ssuming it occurs one incubation period after another case), a case with an unusually long incubation period, a case that resulted from exposure at a different time ( for example, someone who ate leftovers the next day), or an error in recall or in recording the date.

What are the measures of disease control?

A, B, C, D, E. Disease control measures can be directed at the eliminating the agent (e.g., by sterilizing surgical equipment), interrupting transmission (e.g., reducing mosquito population, covering one’s mouth when coughing), preventing entry into a host (e.g., wearing a mask, using insect repellant), or improving host defenses (e.g., by immunization).

What factors influence a health department's decision to conduct a field investigation?

A, B, C, D. Factors influencing a health department’s decision to conduct a field investigation include some related to the health problem itself (e.g., severity of illness, number of cases, availability of prevention / control measures), some relate to the health department (e.g., “corporate culture” for conducting field investigations versus handling it by telephone, available staff and resources), and some relate to external concerns (e.g., public or political pressure).

What is the hallmark feature of an analytic epidemiologic study?

The hallmark feature of an analytic epidemiologic study is: (Choose one best answer) Use of an appropriate comparison group. Laboratory confirmation of the diagnosis. Publication in a peer-reviewed journal.

What is the epidemiologic triad of disease causation?

It is synonymous with survey. The epidemiologic triad of disease causation refers to: (Choose one best answer) Agent, host, environment.

Why is John Snow's investigation of cholera considered a model for epidemiologic field investigations?

John Snow’s investigation of cholera is considered a model for epidemiologic field investigations because it included a: Biologically plausible hypothesis. Comparison of a health outcome among exposed and unexposed groups . Multivariate statistical model. Spot map. Recommendation for public health action.