BACTERIA AND VIRUSES

Both bacteria and viruses can cause diseases, but they are different in many ways.
Bacteria are living organisms. They can live in many places, such as soil, water, and the human body. The smallest bacteria are about 0.4 micron in diameter. Some bacteria in our bodies are helpful, but some can cause infectious diseases such as tuberculosis or food poisoning. Antibiotics are often used to treat infections caused by bacteria.
Viruses are tiny germs that cause diseases in people, animals, and plants. They can cause a range of illnesses, from the common cold or the flu to more serious diseases such as AIDS and Covid-19. As they are very small (0.02 to 0.25 micron), viruses can get into our bodies easily. They are not living things, so they need to enter our bodies to become active. Then, they start to grow and cause the infected cell to make millions of copies of the virus. Vaccines are often used to prevent the spread of diseases caused by viruses.