抗生素的安全使用（英文PPT）do bugs need drugs？PPT.pptVIP

Drying hands with a towel removes 42% more germs than just washing alone. Care should be taken not to spread germs by sharing towels. Use of hot air dryers may actually promote the growth of bacteria on the hands because often the hands are left warm and moist. Handwashing is the best way to stop the spread of respiratory tract infections. Alcohol based hand rubs are effective in killing many bacteria and viruses but need to be at least 60% alcohol to be effective. Alcohol is a denaturing agent and causes immediate and extensive structural damage so that the bacteria are unable to survive. This is in contrast to antibiotics which kill bacteria more slowly by interfering with biological processes. With alcohol-based products the bacteria are quickly obliterated and have no chance of developing a resistance mechanism. The advantages of alcohol based hand rubs are that they can be used when soap and water are not available, are quick to use and cause less skin drying. There are, however, disadvantages. Alcohol will not work in the presence of dirt and grime and are not effective if the hands are visibly dirty. Because these products are broad spectrum some good bacteria are also killed. Importantly, alcohol based agents do not kill many of the germs that cause diarrhea. Because of this, these products should not replace regular washing with soap and water and are not needed in the home. Both bacteria and viruses can cause infections of the respiratory tract, however viruses cause the majority of these illnesses. Bacteria and viruses are very different types of microorganisms - in their structure, the way they cause infections and the ways they can be killed. Antibiotics interfere with the biological processes of bacteria to kill them or to inhibit their growth. Viruses are significantly different from bacteria. Viruses are much smaller, simpler organisms and are not affected by antibiotics. Because of this antibiotics do not work against viral infections. B