Disease Causative Agents

Infectious diseases are named so because they are caused due to “infection” which refers to the invasion by microorganisms. Thus, (1) is the correct answer. 

Syphilis is a bacterial disease which spreads through sexual contact. Tetanus (disease in which muscle contracts) and diphtheria are caused due to microbes and spread through air and soil, etc. Constipation (disease in which stools become hard) is an intrinsic disease, which is not spread from one person to the other.

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

Infectious agents of common cold (virus), pneumonia (bacteria) and tuberculosis (bacteria) are the microbes which transfer through air, i.e. these are air borne diseases and affect our immune system, lungs and respiratory system, respectively. On the contrary, AIDS is caused due to HIV which is transmitted by sexual contact or exchange of body fluids only. Thus, (2) is the answer.

AIDS, common cold and dengue fever are caused by viruses, e.g. HIV, common cold virus and dengue virus, respectively. Tuberculosis is caused by a bacterium named Bacillus calmettie and hence, (2) is the required answer.

Fever and cough last for a small duration and hence, they are acute. On the contrary, elephantiasis is a chronic disease, which lasts for a long time and makes the body and general health poor. In this disease, the person’s limbs, i.e. feet, legs, arms and hands, are highly swollen due to accumulation of water in the cells. The person looks bulky and his limbs are swollen. Hence, it is compared to elephant’s limbs and so the disease is termed “elephantiasis”. It should be noted that now small pox has been eradicated, but when it was prevalent, it used to last for a small time and cause death.

It causes cholera.

It is caused by Shigella Dysenteriae.

This microbe causes Black death (bubonic plague).

Mycobacterium tuberculosis causes TB.

This bacteria is spiral in shape like all the members of spirochaete.

Chloroquine (commonly misspelled as chloroquin) is an antimalarial drug used to treat and prevent malaria. It works by interfering with malaria parasite's ability to digest hemoglobin. It is not used for rabies, sore throat, or tuberculosis.

Infantile paralysis is spread when the stool of an infected person is introduced into the mouth of another person through contaminated water or food (fecal-oral transmission).

Transmissible diseases are those diseases which are communicable by contact with a patient suffering from it, or with some secretion of, or object touched by, such a patient. Dermatophytosis is a contagious fungal infection caused by mold-like parasites that live on the cells in the outer layer of your skin. Hansen's disease or leprosy is contagious disease caused by a bacteria Mycobacterium leprae, but is not easily transmitted.

Variola vera 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 an infected person. Diphtheria (pair of leather scrolls) 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.