What are Pathogens?


An enormous variety of organisms exist, including some which can survive and even develop in the body of the host. If the organism can cause infectious diseases, it is an infectious agent. In this manual infectious agents which cause infection and illness are called pathogens.

Classification of Pathogens

Pathogens are classified into four main categories concerned with the classes of pathogenicity relying on general risk analysis and assessment available under the purview of the present practical and theoretical frameworks. These include:  

Class 1

One of the below criteria has to be covered by the microbial species like:

  1. They should not be part of an identified group of disease causing agents in animals or humans.
  2.  They had been proven to be safe in the past history under conditions without any sort of restrictions physically while despite taking into account the species having the difference in virulence between strains within them.
  3.  The species that belongs to one of the below classes but a particular group of the chain might have fewer genes that could create pathogenicity in animals and humans.  The species of a particular chain might be put in an exceptional position depending on the degree of attenuation.

This would imply that out of categories 2,3 and 4 species, the certain chain would be down graded to a class.

  1.  Both in vivo and in vitro testing, the non-pathogenicity of the species has been demonstrated authoritatively.

Class 2

Species which spread diseases in humans or animals, might not spread to the humans and that has a necessary prophylaxis or therapy.  

Class 3

Species which causes serious disease in humans,  spread to the humans while having the necessary prophylaxis or therapy.  

Class 4

Species that cause serious human disease, which is likely to disseminate in the human population and for which no adequate prophylaxis or therapy exists.

Practise This Question

Maize, rice and wheat are good sources of __________.