This would be likely if mortality were to be 5%-25%. However, should mortality go much higher than that, people will be much too busy surviving for government to be effective.
90% short-term mortality would result in wars within a generation as people try to occupy the vacant spaces. 99% short-term mortality will be near 100% in some areas. 99.9% short-term mortality would leave 7 million and make it a challenge for people to find people to have children.
Many more would starve/be killed by other pathogens/animals/other people. I strongly doubt species extinction, even at 99.9% short-term mortality, unless there is a second wave of nukes/biological weapons/other assorted insanity.