Lecture 25

Question 1

disease outbreak: occurrence of cases of a disease in … of what would normally be expected in a defined …, … or …

Answer 1

excess; community; geographical area; season

Question 2

R0 = … of the virus (i.e. contagion or the number of … expected from one primary case)

Answer 2

reproductive rate; secondary cases

Question 3

R0 <1 then … and will …
R0 = 1 existing infection causes … but won’t …
R0 > 1 then spreading can cause an … or …
model that assumes everyone is naive (no …, no … from previous encounters with the disease) and that there is no way to control …

Answer 3

declining; die out; new infection; spread; outbreak; epidemic; vaccinations; immunity; disease spread

Question 4

Ro is a dynamic number that changes depending on context:

• … period (length of time a person is …)
• … rate (rate of contact with … individuals): how many … it takes to make a person sick , number of … individuals (size of population and … from natural causes, number of individuals … and …, … of pathogen, … rate and …), … prevention
• … rate (how fast it can be …): … of transmission (how does it spread- …, …, etc)

Answer 4

infectious; contagious; contact; naive; disease agents; naive; death rate; infected; recovered; virulence; vaccination; effectiveness; contact; transmission; transmitted; mode; airborne; bodily fluids

Question 5

first case of ebola traced to a … yr old in SE Guinea in Dec. …

Answer 5

2; 2013

Question 6

isolated cases continued to appear in .., but for most affected regions, the end of Ebola virus … had been declared

Answer 6

2016; transmission

Question 7

Ebola first identified in …
normally < … cases/yr
no cases reported between …-…
in fall 2014, there was a separate outbreak of a different … of Ebola in DR Congo, seems unrelated to the epidemic in …

Answer 7

1976; 500; 1979; 1994; strain; West Africa

Question 8

sporadic outbreaks that were very deadly within a community but did not

Answer 8

spread very far

Question 9

Ebola is a … disease

Answer 9

zoonotic

Question 10

zoonotic: transmissible between … and …

Answer 10

animals; humans

Question 11

… percent of all human pathogens are …

Answer 11

60; zoonotic

Question 12

enzootic cycle: new evidence strongly implicates … as the reservoir hosts of ebola viruses, through the means of local enzootic maintenance and transmission of the virus within …populations remain unknown

Answer 12

bats; bat

Question 13

epizootic cycle: epizootics caused by ebolaviruses appear .., producing … among non-human primates and duikers and may precede human outbreaks. epidemics caused by ebolaviruses produce .. disease among humans, with the exception of Reston virus which does not produce detectable disease in humans. little is known about how the virus first passes to humans, triggering waves of human to human transmission, and an epidemic

Answer 13

sporadically; high mortality acute

Question 14

following initial human infection through contact with an infected bat or other wild animal, .. often occurs

Answer 14

human-to-human transmission

Question 15

human-to-human transmission is a predominant feature of

Answer 15

epidemics

Question 16

… of three fruit bat species correlates with regions where ebola outbreaks have occurred

Answer 16

geographic distribution

Question 17

ZEBOV (Zaire Ebolavirus): the species in the West Africa Ebola Outbreak–outbreaks are associated with the … season –> seasonal factors may influence … and … distributions, potentially increasing their contact with …

Answer 17

dry; forage; wildlife; Ebola reservoirs