If the data doesn't match what you want, make it fit. In the end of course it's hard to hide dead people.
This is a recipe for turning a natural disaster into political one, potentially a crisis of legitimacy.
All most people will know, first hand, is the deaths of their immediate circle. The full extent of the calamity can remain a matter of debate.
If there are photos, the government can call them forgeries. If there are anecdotes from health care workers, or in the press, the government can dismiss them as left wing propaganda.
And besides, there are bogeymen on whom one can pin all of one’s own mistakes. Perhaps Soros and Bill Gates developed an electricity-based bio-weapon, and unleashed it, over TCP/IP, to decimate the people of Brazil.