Sample A: Cover Page of Thesis, Project, or Dissertation Proposal

denser populations of hosts occur in habitats suitable for vectors. The distribution of high
risk areas throughout the state could result in rapid statewide spread of the virus if it is
introduced in just one of these areas.
In the previous chapter, risk of establishment of RVF virus across Virginia was
visually represented in Figure 4.15. Based on the epidemiology of RVF and ecology of RVF
virus, domestic animals (cattle, sheep and goats) and wildlife (white-tailed deer) were
included as the principal host groups involved in the initial phase of an outbreak and
consequential virus establishment in local mosquito populations. Areas at medium-to-high
risk of RVF establishment in mosquito populations are located where areas with a higher
probability of competent vector occurrence overlap with densely-populated domestic animal
and/or white-tailed deer areas. In general, the risk of establishment is greatest in the
Northern Virginia, Richmond-Petersburg, and south-western (e.g, Roanoke City/County,
Montgomery County, and Washington County) regions of Virginia.
Estimating the probability of establishment within vectors is an integral part of
estimating the probability of infection to humans. Consequently, human density was
evaluated with respect to risk of RVF establishment to estimate the risk of RVF transmission
to humans (Figure 4.17). As expected, risk of RVF transmission to humans is greatest in
areas of the state with the largest human populations, namely the Northern Virginia,
Richmond-Petersburg, and Hampton Roads areas. High risk in the Northern Virginia,
Richmond-Petersburg, and Hampton Roads regions is associated with high probabilities of
competent vector occurrence, high white-tailed deer population estimates, and dense human
populations. The south-west part of the state (e.g, Roanoke City/County, Montgomery
County, and Washington County), in general, is more rural than the eastern portion of the
137