Question

Causal organisms of any disease are called ______.

Answer 1

Causal agents of disease are organisms that cause the disease. They can be of bacterial, viral, fungal origin. They develop themselves in the host body, thus causing the disease. The period which the pathogens take to infect the host body and cause disease is called the incubation period. The diseased person if has communicated disease should maintain proper hygiene and should be quarantined to decrease the spreading of the disease.

Complete answer:
Causal agents of disease are defined to be agents or organisms which are the real cause of the occurrence of the disease. These causative agents may be viruses, bacteria, fungi, or parasites. Causative agents are called pathogens. They live and procreate in the living body. They enter into a living body, grow, and develop inside the body by gaining the nutrition and nourishment from the living body. The living body provides proper temperature, environmental factors to the respective pathogens. Causative agents or pathogens start growing in the host body by inheriting the required factors from the body and weaken the host body. This leads to the loss of immunity of the host and the immune system starts weakening. Pathogens after weakening the immune system start developing the respective disease in the host body. The pathogens directly damage the tissues or cells of the body, mostly by producing toxins. Bacterial toxins include tetanus, botulism. Viral toxins include AIDS, mumps. Fungal toxins include ringworms, rashes. Pathogens for diseases like smallpox are totally eradicated from the world. Diseases are like a plague, leprosy is under control. So, the causal agent of any disease is called a pathogen.

Note: Non-pathogenic organisms are organisms that do not cause any diseases. Some of these non-pathogens become pathogenic after entering the host body. Pathogens after entering the host body, start multiplying and growing within the incubation period. The incubation period is defined as the period between the entry of the pathogen and visible symptoms of the disease.