But infectious bacteria can make you ill. They reproduce quickly in your body. Many give off chemicals called toxins, which can damage tissue and make you sick. Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.
Getty Images/Fuse. Head down: Jet lag symptoms include feeling sleepy during the day in your new time zone. Jet lag is what we call it when your body is reacting to these changes in your environment, which is basically your body taking time to adjust to its new place and time. Symptoms include feeling sleepy during the day in your new time zone, but also having a troubled sleep at night.
The term jet lag is used because before the arrival of passenger jet aircraft, it was uncommon to travel far and fast enough to cause jet lag. Travel by propeller-driven aircraft, by ship or by train were slower and of more limited distance than jet flights, and thus did not contribute widely to the problem.