Average death rates from flu are about 0.06 percent. Death rate from the Spanish Flu was between 2.5 and 5 per cent (depending on your source). So far the mortality rate in Mexico (if you trust the figures of 1600 reported cases and 149 reported deaths) is about 9.3 per cent or roughly double (or more) the death rate from the Spanish Flu which was the most deadly pandemic in history. Now whether or not the strain in the US is more benign or not remains to be seen. My concern would be that if Mexican nationals cross the border illegally to avoid the epidemic and are already infected, then they would probably avoid going to the doctor so their illegal status would not be detected. That would make it easier for it to spread as well as giving it more of a chance to mutate. Just my 2 cents.
According to a doctor on Cavuto on Fox News today there is about a one percent mortality rate to this flu so he thinks Mexico has about 100,000 cases or more.
There's the rub. Based on actual, not reported, cases, the death rate would be much lower.