Volume 13, Number 7—July 2007
Effects of Internal Border Control on Spread of Pandemic Influenza
|Reproduction no. (R0)||1.5–3.5||Mills (14)|
|Infectivity function (ρ)||Flat or peaked†||Longini, Ferguson (7,8)|
|Latent period||1 (1–2 in sensitivity analysis) d(s)||Ferguson (6)|
|Infectious period||5 d||Literature suggests 4–7 d in adults (6,7)|
|Mixing||Homogenous (within city)||Modeling literature (15)|
|Propensity to travel||Everyone equal||Assumption|
|Populations||Sydney (4.2 million), Melbourne (3.6 million), Darwin (110,000)||ABS figures (16)|
|Travel rate‡ Sydney ↔ Melbourne (weighted by stay length)||(4.7 × 103, 8.9 × 103)||BTRE figures (17,18), NSW, and Victoria Tourism reports (19,20)|
|Travel rate‡ Sydney ↔ Darwin (weighted by stay length)||(9.2 × 104, 4.4 × 103)||BTRE figures (17,18), NSW, and NT Tourism reports (19,21)|
|Travel restrictions||20%,10%, or 1% of current levels||Assumption|
|Time between 20 current cases in city 1 and city 2 (T20)||Random variable (T20), different for each simulation. Median value over all simulations is given by m20.||Output variables used to measure effect of travel restrictions|
*ABS, Australian Bureau of Statistics; BTRE, Bureau of Transport and Regional Economics; NSW, New South Wales; NT, Northern Territory.
†See Figure 1, panel C, for shapes used.
‡This assumes a constant travel rate over the year with no seasonal variation in travel volumes.
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