ABOUT INDIRECT AND DIRECT METHODS BY WHICH PATHOGENS CAN BE TRANSMITTED



DIRECT CONTACT :
                                     
The passing of a pathogens to an uninfected person is called transmission. The entry of the pathogens into body is known as infection. The person[or animal] in which the pathogen lives and breeds is to be a host for that pathogen. Some pathogen pass from one person to another where there is direct contact between an infected person and uninfected one.




INDIRECT CONTACT :

 Most pathogens ar transmitted indirectly. Indirect methods of transmission include the following:
  • Through the respiratory passageway cold and influenza viruses are carried in the air in tiny droplets of moisture. Every time someone with these illnesses speaks, coughs or sneezes, millions of viruses are propelled into the air. If you breathe in the droplets, you may become infected.
  • In food or water bacteria such as Salmonella can enter your alimentary canal with the food that you eat. If you eat large number of these bacteria, you may get food poisoning. Many pathogens, including the virus that cause Poliomyelitis and the bacterium that causes cholera, are transmitted in water. If you swim in water that contains these pathogens, or drink water that containing them, you run the risk of catching the diseases.
  • A vector is an organisms that carries a pathogens from one host to another. Dogs, skunks, raccoons and bats are vectors for the rabies viruses, which is transmitted in their saliva when they bite. Anopheles mosquitoes are the vector for malaria. The female mosquitoes may have the protoctist pathogens Plasmodium in their saliva, which they inject into your blood when they bite. 

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