Antibody by Chris Williams

Alice needs a vacation to escape her family, unemployment, and a global pandemic. When the world shuts down due to a newly discovered virus, Zenith Pharm, a major drug manufacturer, reveals a breakthrough in vaccine development and offers individuals an all-expense-paid trip to a remote resort with an on-site testing facility. The catch: a little blood work, a little medicine-no big deal, right? 

Between the constant parties and pool-side recreations, Alice and the other guests experience haunting nightmares, and people begin to disappear. Something dark lurks behind this exclusive resort, and Alice learns that Zenith Pharm has other, more malicious plans for its guests.