Question

Name some diseases which are caused by
a) bacteria
b) protozoan
c) virus

Answer 1

Hint: Bacteria, protozoa, and viruses are microorganisms that can cause several diseases in humans and other mammals as well. They can cause infections in different parts of the body. The mode of transmission for these diseases could be contaminated food or water, air droplets from an infected person, contact with a surface containing a microorganism and many more.

Complete answer:
Diseases caused by Bacteria
When bacteria invade a particular part of the body, it can lead to an infection or disease.
> Some of the bacterial diseases are:
• Tuberculosis: it is a disease caused by the bacterium Mycobacterium tuberculosis. This disease predominantly attacks the lungs; however, it can also affect the spine and brain.
• Typhoid: it is a life-threatening disease caused by Salmonella typhi and paratyphi species. It causes fever, vomiting, etc.
• There are many other bacterial diseases – Cholera, Urinary Tract Infection, Folliculitis, Meningitis, Syphilis, etc.

Diseases caused by Protozoan
Protozoa are single-celled microorganisms that are found in moist environments.
> Some of the diseases caused by protozoans are:
• Amoebiasis: this is a disease that is caused by Entamoeba histolytica. It can cause diarrhoea which may contain blood, abdominal pains and cramps, and vomiting. It can also lead to ulcers in the intestines.
• Tripanosomiasis: it is a disease that can be caused by two related species of Trypanosoma – B. gambiense and T. rhodesiense. It is characterized by anaemia, cachexia, fever, etc.
• Other protozoan diseases are – Malaria, Leishmaniasis, Diarrhoea, etc.

Diseases caused by Virus
A virus is a microorganism that causes disease by incorporating its DNA with the DNA of a host organism.
> Some of the diseases caused by virus are:
• Dengue: it is caused by the dengue virus. Symptoms are headache, fever, body ache, and vomiting.
• Chicken pox: this is a disease caused by the Varicella Zoster virus. It is characterized by red spot-like rashes all over the body.
• Other viral diseases include – measles, common cold, AIDS, etc.

Note: Bacteria can be of two types – good and bad. Almost all the bacterial diseases are caused by pathogenic, i.e. bad bacteria.
Protozoan diseases can be caused with the help of certain vectors, for example, a mosquito carries the Plasmodium of Malaria.
Viral diseases can be extremely widespread and cause infections in a large population, for example, the COVID-19 pandemic