You haven't been following this problem closely have you?
No, he's one of the "it didn't happen with SARS, so it can't happen with anything else" or "our technology has prevented a pandemic for the last 87 years, why worry" types. Whistling past the graveyard invincibility. Damn I used to hate having those types in my platoon - they always turned into mortar or grenade magnets.
Which problem am I not following? The potential for human-to-human transmission of bird flu? Nope, I'm read up on that. Potential for airborne transmission of Marburg? Nope, I'm read up on that. Neither are likely for reasons you'd need to crack a biochemistry book to understand.
Influenza is the greatest threat, but the world, while smaller due to air travel, is also cleaner and has progressed in terms of public health by orders of magnitude since the 1910's. Yacking about 30-40% of the world's population dying is just hot air.