Disease Causative Agents

Antibiotics are the preparation made from modified bacteria, which act against any bacterial infection, whereas, pathogen refers to the disease causing organisms. Carrier organisms transmit disease from a diseased person to a healthy one and invaders refer to any organisms, which enter into our body irrespective of the fact whether it is useful or harmful. 

Pathogens are microorganisms that cause disease, including bacteria, viruses, fungi, and protozoa. Antibiotics are drugs used to treat bacterial infections, not the organisms themselves. 'Invaders' is too vague a term. Carriers are organisms that harbor pathogens without showing symptoms themselves.

Communicable diseases spread from person to person through pathogens like bacteria or viruses. Cholera (waterborne bacterial), chickenpox (viral), and tuberculosis (airborne bacterial) are all infectious communicable diseases. Arthritis is a non-communicable chronic condition involving joint inflammation and degeneration.

A common disease which develops among the coal mine workers is silicosis. Exposure to coal mine dust and crystalline silica results in pneumoconiosis with initiation and progression of pulmonary fibrosis.

Virus causes Hepatitis-B.

Allergy is not a communicable disease.

Antibodies attack the pathogen which enters the body, and destroys it. This gives protection to our body,

Virus causes foot and mouth disease in cattle.

Bacillus anthracis causes anthrax.

Typhoid fever is caused by the bacterium Salmonella typhi and not by any virus.

This option is correct because poliomyelitis is usually spread from person to person through infected faeces entering the mouth. It may also be spread by food or water containing human faeces and less commonly from infected saliva. Balantidiasis is a zoonotic disease and is acquired by humans via the feco-oral route from the normal host, the pig, where it is asymptomatic. Contaminated water is the most common medium of transmission.

This option is correct because all are viral diseases. Chikungunya is a viral disease transmitted to humans by infected mosquitoes. Rabies is a viral disease that is spread most often from the bite of a rabid animal to another animal or to a human. Poliomyelitis is a highly contagious and infectious disease caused by poliovirus. Common cold is a mild viral infection of the nose, throat, sinuses and upper airways.

This option is correct because all are bacterial diseases. Tuberculosis (TB) is an infectious disease that is caused by the bacterium Mycobacterium tuberculosis. Anthrax is an infection that is caused by the bacterium Bacillus anthracis. Tetanus or lockjaw is a serious infection caused by the bacterium Clostridium tetani. Cholera is an acute epidemic infectious disease caused by the bacterium Vibrio cholerae.

This option is correct because asthma, scurvy and diabetes are non-communicable diseases.

This option is correct because smallpox is a highly contagious disease. People get infected with smallpox virus by inhaling droplets of saliva, which are full of virus, during face-to-face contact with the infected person. Diphtheria is spread (transmitted) from person to person, usually through respiratory droplets, from coughing or sneezing. Influenza viruses are spread mainly by droplets made when people with flu cough, sneeze or talk.