During one part of the movie, they have a camera shot across the deck of the cruise ship. In that shot the signature "Whale Tail" of the Carnival Cruise Line is shown. All other pictures of the ship are without that smokestack and do not resemble a Carnival cruise ship.
The doctor says, "Trichothecene mycotoxin, the anthrax virus." Anthrax is a bacterium, not a virus, and it has no connection with trichothecene mycotoxin, which is a toxin produced by trichothecene fungi, which have no connection with viruses, bacteria, or anthrax.
During the escape, someone makes a remark about the impending explosion of the submarine Roosevelt "...turning this thing into calamari." Calamari is squid, not octopus.