Epidemiology Quiz Chapter 12
Attack rate is
number of persons who ate a specific food and became ill / total number of persons who ate the specific food similar to the incidence rate of a disease of short duration
An important point about the agent-host environment model (the epidemiologic triangle) of epidemiologic investigation is that:
Diseases are multi-causal
True or False: Herd immunity must be 100% to confer protection to a group.
False
An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. 65 people had fever and diarrhea. 5 of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. The attack rate of salmonellosis was
28.2%
The table below shows the mumps experience of children in 390 families exposed to mumps by a primary case within the family (include picture) The secondary attack rate among children aged two to four years is
33%
An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. 65 people had fever and diarrhea. 5 of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. The ratio of severe cases to other clinically apparent cases was
5/60
Which of the following examples involves indirect transmission of disease? A. Malaria B. Hepatitis caused by needle sticks C. HIV/AIDS D. Pneumoconiosis
A and B
Which of the following infections shows a high subclinical/clinical ratio (inapparent/apparent ratio) A. childhood hepatitis B infections B. human papillomavirus infections C. hepatitis A among children younger than 6 years old D. adult hepatitis A infections
A, B, and C
What factors comprise the epidemiologic triangle?
Agent, Host, Environment
An attack rate is an alternative incidence rate that is used when: A. describing the occurrence of food-borne illness or infectious disease B. the population at risk increases greatly over a short time period C. the disease rapidly follows the exposure during a fixed time period D. all of the above
D
The CDC published an article concerning the high rate of foot fungal disease in New Orleans. The article explains that there has been a high rate of foot fungal disease in New Orleans for decades. Foot fungal disease in New Orleans is best described as
Endemic
True or False? Antigenicity of an infectious agent is measured by the secondary attack rate.
False
True or False? Colonization refers to the spread of plague to the Americas by settlers from Europe.
False
True or False? The case fatality rate is the same thing as the mortality rate for a disease
False
True or False? The presence of an infectious agent is sufficient for outbreaks of infectious disease to occur.
False
True or False? When an individual comes into contact with a piece of clothing that subsequently infects him or her that piece of clothing is a fomite and the infection is direct.
False
True or false? Incubation period refers to the time between the start of an infection and the beginning of the period of communicability.
False
Host factors in the causation of disease include
Genetic factors
Someone suggests immunization as a means of reducing disease, specifically the feared UJ. What part of the disease cycle is he or she trying to affect?
Host
You have just finished administering a food/drink questionnaire to ill and non-ill participants in a Minnesota summer picnic party. The ill individuals developed moderate to severe diarrhea 16-46 hours after the picnic. Six persons experienced vomiting. (Include data picture) Which food item appears to be the most probable vehicle for the salmonella (agent) infection associated with the illness?
Ice cream
An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. 65 people had fever and diarrhea. 5 of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. Foods served at the luncheon included home-canned olives, chicken salad, homemade flavored drink mix, freshly baked rolls, and raw vegetables. Based on your understanding of foods that potentially are capable of transmitting salmonella, the most likely source of the outbreak was
The chicken salad
True or False: The reservoir for Q fever is infected livestock (cattle, sheep, or goats)
True
True or False? A secondary attack rate is used to show the spread of disease in a household.
True
True or False? Herd immunity refers to protection of a population against an infectious disease when a large proportion of individuals are immune through either vaccinations or past infections.
True
True or False? If a disease is fatal, virulence can be measured by the case fatality rate.
True
True or False? In 2010, the groups most affected in the US by TB were foreign-born individuals and racial and ethnic minorities.
True
True or False? Lyme disease is an example of a disease transmitted by arthropod vectors.
True
True or False? Reasons for the resurgence of tuberculosis include the increasing prevalence of HIV infection.
True
True or False? Vaccine preventable diseases include Haemophillus influenzae type B (Hib)
True
True or false? Vectors can be considered as one way in which infectious diseases can be transmitter.
True
In two communities of similar size and age structure (A and B), there were outbreaks of viral illnesses (Virus A in community A, and Virus B in community B), both of which were traced back to a single source. Exposure to these viruses in each community confers permanent immunity. In community A, 200 susceptible people were exposed to an index case, 150 people were infected (not including the index case), 75 people became ill, and 40 people died. In community B, pathogenicity was 40%, infectivity was 90%, and virulence was 60%. Which virus was most pathogenic?
Virus A
In two communities of similar size and age structure (A and B), there were outbreaks of viral illnesses (Virus A in community A, and Virus B in community B), both of which were traced back to a single source. Exposure to these viruses in each community confers permanent immunity. In community A, 200 susceptible people were exposed to an index case, 150 people were infected (not including the index case), 75 people became ill, and 40 people died. In community B, pathogenicity was 40%, infectivity was 90%, and virulence was 60%. Which virus had the greatest infectivity?
Virus B
In two communities of similar size and age structure (A and B), there were outbreaks of viral illnesses (Virus A in community A, and Virus B in community B), both of which were traced back to a single source. Exposure to these viruses in each community confers permanent immunity. In community A, 200 susceptible people were exposed to an index case, 150 people were infected (not including the index case), 75 people became ill, and 40 people died. In community B, pathogenicity was 40%, infectivity was 90%, and virulence was 60%. Which virus was most virulent?
Virus B
Schistosomiasis is an example of
a biological agents-helminth
A person with an inapparent infection
can transmit the infection to others
The site where a disease agent enters the body is the
portal of entry
Community A receives its water from several sources. The water source for causing an outbreak of disease X is unknown. The evidence to determine which suspected water supply is responsible would be:
the attach rates for disease X in those who did not drink from each water supply
The public health officer from Long Beach complains to you about the dreaded Pacific Pox. The health officer says, "If people catch the Pox, they suddenly get the urge to dance in the sand and fall dead on the beach within the hour." There are no survivors to interview so you deduce
the case fatality rate of the Pox must be high
