Why? Because the author didn't bother to examine the number of violent deaths or accidents for doctors and biologists in 2000, or 1999, or 1998.
Without knowing that, it's impossible to say whether there is anything remotely unusual occuring recently at all. But, of course, conspiracy nuts don't bother with baseline reseach because it isn't exciting and fun...and it's a LOT of work.
And it's their responsibility to do it..it's their wacky theories. If it's easier to do (like data on air crashes, etc.) I'll do it from time to time.
Also, as an aside, "Nguyen" is an insanely common Vietnamese name. Means as much as if the researcher and the NY woman were both named "Smith."