# Thread: Swine Flu (H1N1) Modeling

1. ## Swine Flu (H1N1) Modeling

Sorry, I'm new here and not entirely sure which part of the forum to post this in.
Would really appreciate it if someone could be bothered to help.

The following numbers show the amount of registered cases of H1N1 (swineflu) in the USA in 2009.

Days after the 17th of May 2009 : | 0 days | 8 days |
People with swineflu : | 4714 people | 6552 people |

Initially, the flu pandemic could be described by the formula

y = b * a^x

where y is the amount of people with swineflu, and x is the number of days after May 17. 2009

a) Find the numbers a and b

b) Calculate the doubling time constant
Describe how this number explains the development of the flu.

(Does this have something to do with (log 2/log(x)???

c) When will there be more than 21,000 people with swineflu according to the model?
Comment the model, when a different source informs you that the amount of people with swineflu will exceed 21,000 after 36 days.

2. when x=0, y=4714 so b=4714

when x =8, y=6552 so 4714a^8=6552. a=(6552/4714)^1/8

3. Continuing
a=1.042 to 3 dp. I will use the full calculator display in further working.
b) we want the vaule of x when y=2*4714=9428
a^x=9428/4714=2
xlog(a)=log2
x=log(2)/log(a)=16.8 to 3 S.F. So flu spreads quickly

c) again solving for x. a^x=21000/4714 so $x=log(21000/4714)/loga=36.3$ so your answer is 37 days. So the model looks pretty accurate.