Disease Causative Agents

Communicable (infectious) diseases spread from person to person through pathogens. Cholera (bacterial Vibrio cholerae through water), Common cold (viral through air/droplets), and Chickenpox (varicella-zoster virus through air/droplets) are all communicable. Anemia is a non-communicable condition - it is a deficiency disease caused by lack of red blood cells or hemoglobin (from iron deficiency, vitamin B12 deficiency, blood loss, or genetic conditions like thalassemia), not by infectious agents.

This option is correct because hepatitis B is an infectious illness of the liver caused by the hepatitis B virus. 

This option is correct because whooping cough is caused by Bordetella pertussis.

 Chicken pox is caused by the varicella-zoster virus (DNA virus).

Anthrax is an infectious disease caused by the gram-positive, spore-forming rod-shaped bacterium Bacillus anthracis.

This option is correct because both diseases are caused by gram-positive bacteria.

This option is correct.

This option is correct because rabies virus is a neurotropic virus that causes rabies in humans and animals. These viruses are enveloped and have a single-stranded RNA genome with negative-sense.

This option is correct because Kawasaki disease is an auto-immune disease in which the medium-sized blood vessels throughout the body become inflamed.

This option is correct because all are correctly matched.

This option is correct.

Haemophilia is a disease in which the blood does not clot whenever there is a wound/injury and it is a genetic disorder. It is not caused or spread by infectious agents. Thus, it is a non-infectious disease. Cholera, typhoid and malaria are caused due to microorganisms, which cause infection or disease in the digestive system, immune system and blood (also liver), respectively.

Disease-causing organisms, i.e. causative agents are transferred from a diseased person to a healthy person by an organism which itself does not get the disease. Such an agent is called “vector”.

Tuberculosis is a chronic disease as it can last for a long time, even as much as a lifetime.

Rabies virus is carried by vectors, which contain the virus and transmit it from a diseased person to a healthy person. The vectors for rabies are animals (dogs and cats usually).