Question

Diphtheria is caused by
a. Poison released by the living bacterial cell into the host.
b. Poison released from the dead bacterial cell into the host.
c. Poison released by the virus into the host.
d. Excessive immune response by the body of the host.

Answer 1

Hint: Microbiology is the study of the microbes (bacteria, virus, fungi, etc.) where the clinical microbiology part deals with the pathogens causing diseases and infections in humans and the mode of entering into the host. Host is the organism that lets the parasite dwell and uses its mechanism. Infections can be contagious and sometimes not.

Complete answer:
Diphtheria is caused by the pathogen Corynebacterium diphtheriae which is a bacterium. It is a very serious infection in which the bacteria makes a poison (toxin) and releases inside the host. It is a droplet infection which is easily transmitted from person to person via coughing or sneezing.

The toxin released is very harmful for a person and easy to get infected and it is released by the living bacterial cell. It can get people infected even on touching ulcers of any person or even touching open sores. Besides being a respiratory droplet infection it can also cause diphtheria skin infection.

As stated above, this infection is a bacterial infection not a viral infection. It is caused by the strains of Corynebacterium diphtheria which can make toxins. Sometimes it is asymptomatic as well.

In case of any disease the immune system gets affected massively and due to the toxin released by the bacteria its passive immunization. Lymph nodes become enlarged and platelets become low in count even resulting in the paralysis of the patient. It lowers the immune activity.

Hence, The correct answer is option (A).

Note: Though this is a very serious infection it is preventable by vaccine and by antibiotics which acts on the toxins to neutralize it. Penicillin can be used as an antibiotic for treating this or erythromycin. It takes four to six weeks for an infected person to recover from bacterial infection.