leviathan (1989)

"I know this now... the Russians deliberately sank that ship to protect themselves. Maybe to protect us all."
An undersea mining facility comes across a sunken Russian sub, the Leviathan. A sub that looks like it has been deliberately sunk. But it's only when one of the crew drinks some vodka from the wreak that the trouble starts, as the crewman starts to genetically modify, and is hungry for blood.
Mix The Thing with Alien and add a dash of The Abyss, and you have this unremarkable thriller.

the cassandra crossing (1976)

"I may be the only doctor for a thousand potential plague victims if I haven't caught it myself."
A contagous and deadly virus is unleashed by terrorists on a European train. Whilst the passengers start dropping like flies, the military (Burt Lancaster) try to cover up the problem, ignoring the doctors who argue about how to save those infected.
Another disaster epic, chock full of Hollywood stars, whose plight we are meant to agonise over. But to be honest, I never got to know them enough to care!