I think antibiotics are not a threat because lots of people have died without Antibiotics. Antibiotics can treat sicknesses like strep throat, most sinus infections, pneumonia and more. Antibiotics begin to work right after you take it. However you start feeling better 2-3 days after you've taken it. When a person takes Antibiotics, sensitive bacteria are killed. But resistant ones may stay and grow. Th first antibiotic was penicillin found by Alexander Fleming. Antibiotics could either kill or slow down the growth of bacteria.