Seemingly within the realm of conspiracy theory, but:

When half a million Americans died and nobody noticed | News | The Week UK:

"Typical was the headline on a short article that ran in the 19 April 2005 edition of USA Today: 'USA Records Largest Drop in Annual Deaths in at Least 60 Years.' During that one year, American deaths fell by 50,000 despite the growth in both the size and the age of the nation's population. Government health experts were quoted as being greatly "surprised" and "scratching [their] heads" over this strange anomaly, which was led by a sharp drop in fatal heart attacks.

For his Chinese melamine/Vioxx comparison, Unz went back to those 2005 stories. Quick scrutiny of the most recent 15 years worth of national mortality data provided on the US Government's Centers for Disease Control and Prevention website offered Unz some useful clues.

"We find the largest rise in American mortality rates occurred in 1999, the year Vioxx was introduced, while the largest drop occurred in 2004, the year it was withdrawn," says Unz. "Vioxx was almost entirely marketed to the elderly, and these substantial changes in the national death-rate were completely concentrated within the 65-plus population."