Volume 22, Number 11—November 2016
Research
Epidemiology of La Crosse Virus Emergence, Appalachia Region, United States
Table
Variable | Tree-hole model | Tiger model | Tree-hole/tiger model† |
---|---|---|---|
Parameter sets with LACV persistence, % |
46 |
0.20 |
24 |
End-of-season host seroprevalence rate, % | |||
Mean | 89 | 79 | 84 |
Median | 99 | 88 | 97 |
Maximum |
100 |
100 |
100 |
Midseason host seroprevalence rate, % | |||
Mean | 65 | 12 | 18 |
Median | 74 | 8.9 | 12 |
Maximum |
100 |
38 |
98 |
Peak no. infected mosquitoes, per hectare | |||
Mean | 32 | 58 | 23 |
Median | 22 | 50 | 16 |
Maximum |
331 |
200 |
222 |
Peak mosquito infection rate, % | |||
Mean | 4.5 | 1.6 | 1.9 |
Median | 3.5 | 1.5 | 1.3 |
Maximum |
27 |
5.3 |
15 |
Average mosquito infection rate, % | |||
Mean | 2.0 | 0.44 | 0.80 |
Median | 1.6 | 0.33 | 0.57 |
Maximum |
13 |
1.8 |
6.8 |
Maximum human transmission, infections per month per person per hectare | |||
Mean | 15 | 59 | 14 |
Median | 8.6 | 40 | 7.9 |
Maximum |
251 |
247 |
221 |
Timing of peak human transmission | |||
Mean | Aug 14 | Sep 21 | Aug 23 |
Median | Aug 10 | Sep 28 | Aug 21 |
Earliest | Jun 21 | Aug 26 | Jun 26 |
Latest |
Sep 30‡ |
Sep 30‡ |
Sep 30‡ |
End-of-season egg infection rates, % | |||
Mean | 0.63 | 0.08 | 0.28 |
Median | 0.49 | 0.07 | 0.20 |
Maximum | 5.0 | 0.32 | 2.2 |
*All metrics beyond the first row are only calculated for the subset of simulations that gave infected mosquitoes. LAVC, La Crosse virus.
†We avoid reporting minimum values since these are likely to depend on the threshold that we selected for determining disease persistence (see LAC Dynamics, at http://www.clfs.umd.edu/biology/faganlab/disease-ecology.html).
‡In these systems, the abundance of infected mosquitoes was still increasing at the end of the season, indicating that infection rates do not slow before the decline in mosquitoes at the end of the summer.
Page created: October 18, 2016
Page updated: October 18, 2016
Page reviewed: October 18, 2016
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