Infectious agent

Question 1 Name the diseases caused by virus?

 Question 2 Name the diseases caused by bacteria?

Question 3 Name the diseases caused by worms?

Question 4 Name the diseases caused by Protozoa?

Question 5 What are antibiotics?

Question 6 Why antibiotic does not work against viral infection?

Question 7 How does antibiotic work against bacterial infection?

Infectious Agent

Viruses, bacteria, fungi, protozoa, different kind of worms etc.

Viruses-common cold, influenza, dengue, fever, AIDS(they live inside host cell, multiply very quickly)

Bacteria-Typhoid, cholera, tuberculosis, anthrax(they also multiply very quickly)

Fungi-Skin infection

Protozoa-malaria, kala azar

Worms- Elephantiasis, intestine worm infection (multiply very slowly)

Many important life processes are similar in the bacteria group but not shared in virus group. The drug that block one of these biochemical mechanism in one member of the group will be effective against many other members of the group. But same drug will not work against a microbe belonging to a different group.

Antibiotic commonly block biochemical pathway important for bacteria. They work against many species of bacteria, rather than simply working against one.

For Example : Many bacteria make a cell wall to protect themselves. The antibiotic penicillin blocks bacterial processes that build cell wall. As a result, the growing bacteria become unable to make cell wall and die easily.

Viruses do not use these pathways at all, that is why antibiotics do not work against viral infections.

If we have a common cold, taking of antibiotic does not reduce the severity or duration of disease. Instead our body secrete an anti viral protein called interferon to combat virus of cold.