Issue #5 of DCeased had the heroes seemingly managing the zombie anti-life infection's spreading, and preparing plans of evacuation. This was right until an infected Martian Manhunter appeared out of the blue, killing and turning
Flash, whom Superman had to kill to prevent further spreading, but got infected himself in doing so.
But how did Martian Manhunter get infected in the first place? Admittedly the whole point of DCeased is that no one is really safe (and you can throw pretty much anything in alternate universes), but still:
- infection by screen is unlikely, as the issue showed the heroes taking down the Internet and any kind of broadcast device. Had Martian Manhunter been infected prior to that, he'd have been put in motion right away (the anti-life equation doesn't waste any time), and it's not like he'd have difficulties locating and traveling to the heroes' location;
- he is easily one of the most powerful characters in the DC universe. The (rare) persons who'd be able to get the drop on him were still uninfected until then;
- it might be an accident (it's probably one), but this is not confirmed.
No explanation is given in the comics, and it might just be a case of "the writers made it that way, deal with it", but I'd like a confirmation. Besting Martian Manhunter is no trivial thing; the zombies aren't utterly brainless but setting him up with fire seems too sharp for them.
Googling stuff like dceased how Martian Manhunter got infected
doesn't seem to yield anything so far.