 Because you care about me. As humans, we share the world with different microbes like bacteria. Our immune system is great at fighting the bad microbes, but sometimes it can't do it alone. In these cases, we rely on antibiotics. Antibiotics were first discovered in 1928. They work by specifically killing bacteria and have been lifesaving. From syphilis to tuberculosis, antibiotics have prevented many epidemics and saved millions of lives. So how do antibiotics work? They work mainly by blocking the production of some proteins in bacteria. Because of this specificity, antibiotics are really good at killing bacteria, but are relatively harmless to everything else, including human cells and viruses. However, since their discovery, antibiotics have been used more and more when they are not absolutely necessary. People are now using antibiotics for a whole range of things. For example, to prevent cattle from being infected by bacteria and to make them larger. To treat small infections, which could clear on their own. Or when someone is infected by a virus, such as because of this broad use of antibiotics, we are now seeing natural selection take place right before our eyes. To understand natural selection, let's take 1 billion bacteria. Each of these 1 billion bacteria are slightly different from each other with a slightly different DNA sequence. Let's say that one of these bacteria, here in red, has a spot that allows it to survive. This special DNA sequence has arisen randomly over time. Now let's say 1000 bacteria infect us. This would probably include all of the blue bacteria. In this case, antibiotics would work and cure us. However, over time, if we overuse antibiotics, especially in cases when they are not necessary, we are killing off the majority of the blue bacteria. This provides an opportunity for the red bacteria to start dividing, and slowly the red bacteria will take over. Now in this new scenario, if we are infected, antibiotics won't be able to cure us since the red bacteria have a special DNA sequence that allows them to survive with antibiotics. We call them antibiotic-resistant. But worse yet, these antibiotic-resistant bacteria could then cause epidemics by spreading from person to person, by dividing and making more resistant bacteria, but also by giving their special DNA to other bacteria and make those bacteria resistant as well. The cycle could get out of control, with no antibiotics to stop it. We want antibiotics to work when bacteria infect us. If we keep using antibiotics outside of a bacterial infection, for example to cure the common cold, we are giving an opportunity for the resistant bacteria to take over since they have an advantage in the presence of antibiotics. This could be devastating to the future of healthcare. We are now at a time similar to the pre-antibiotic era, where a simple bacterial pneumonia could kill you. A group led by Hossam Zewawi has recently compiled a series of studies looking at antibiotic resistance in the Gulf Cooperation Council countries, including Kuwait, Qatar, and Saudi Arabia. Scientists have found antibiotic-resistant bacteria to cause major epidemics in hospitals that have forced hospitals to close to prevent the spread, which is a significant economic cost. Antibiotic-resistant bacteria were found in surprising places, in seawater from dumping sewage containing resistant bacteria, and in food from using contaminated water to water crops. Once resistant bacteria have taken over, they can spread easily. In dust storms, they can transfer bacteria along long distances of more than 5,000 kilometers and by passenger travel. These problems in the Gulf Cooperation Council countries are prevalent because antibiotics can sometimes be purchased without a prescription, and healthcare professionals and visitors often don't obey hand hygiene rules. This helps resistant bacteria spread. So what can we do as citizens of the world to prevent the spread of antibiotic-resistant bacteria? Don't use antibiotics when you don't have a bacterial infection. Wash your hands when in a medical facility. As researchers, we need to work on developing new antibiotics that specifically target resistant bacteria. Because antibiotic resistance is so easily transmitted from bacteria to bacteria, from person to person, and from country to country, this is a global issue, and we need to be vigilant with how we use our antibiotics, like all other resources, to make sure they are still around for future generations.