Antibiotic is a drug produced by certain microbes. Antibiotics destroy other microbes that damage human tissues. They are used to treat a wide variety of diseases, including gonorrhea, tonsillitis and tuberculosis. Antibiotics are sometimes called "wonder drugs" because they can cure diseases such as meningitis, pneumonia and scarlet fever. But when the antibiotics are overused, or misused, these drugs make a person sensitive being attacked by a superbug.

   Antibiotics do not always distinguish between harmless and dangerous microbes. If a drug destroys too many harmless micro-organism, the pathogenic ones -the dangerous microbes- will have a greater chance to multiply. This situation often leads to the development of a new infection called superinfection.

    Extensive use of some antibiotics may damage organs and tissues. For example, streptomycin, which is used to treat tuberculosis, has caused kidney damage and deafness.

   Resistance to antibiotics may be acquired by pathogenic microbes. The resistant microbes transfer genetic material to non-resistant microbes and cause them to become resistant. During antibiotic treatment, non-resistant microbes are destroyed, but resistant types survive and multiply.

   To avoid the side effect of antibiotics, you’d better not urge your doctor to prescribe antibiotics. Keep in mind that antibiotics are only useful for bacterial infections and have no effect on viruses, so they cannot be used for children pox, measles, and other viral diseases.

What are discussed in paragraph two and four?