The percentage of individuals currently in the US that are susceptible (virtually all individuals before 1958 or so likely got measles) and >95% vaccination rates that were present up until 2004 suggests a current susceptible population of only 1% or so. Given that there is no animal host for measles and that the virus was nearly eradicated from the US the rates of measles infections are very low at present the absence of deaths is not surprising... from CDC
Number of measles cases by year since 2010
Year Cases
2010 63
2011 220
2012 55
2013 187
2014 667
2015 188
2016*70
*Cases as of December 31, 2016. Case count is preliminary and subject to change. Data are updated monthly.
In general measles infections have been less than 1 case per million in the US from 1997 to present with 2014 being the notable exception. We haven't seen any deaths but infection rates are in general less than 1 per million at present (0.000001%) not the previous pre-vaccination rate of 1.875-2.5%
The mortality rate for measles is about 10% in undernourished populations around the world.
The low mortality rate in the US during various outbreaks is due to the general good health of the population and the high level of medical technology widely available even in rural areas.
So if we have a lot better rates than 91% AND the # of deaths is still zero, what are you worried about exactly?
And if you saw evidence that the number of deaths from the MMR vaccine was greater than 0, would that influence your viewpoint at all?