Cabin Fever: Patient Zero

Cabin Fever: Patient Zero is a 2014 American science fiction horror film directed by Kaare Andrews and written by Jake Wade Wall; it serves as a prequel to Cabin Fever, and the third installment of the Cabin Fever franchise. Starring Ryan Donowho, Brando Eaton, Jillian Murray, Mitch Ryan, Lydia Hearst and Sean Astin; the plot centers around a bachelor party on an isolated island, which inadvertently releases the disease from the previous two installments.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

Poster © the film's rights holders.