Disease Vectors and Pathogens

Malaria is transmitted by Anopheles mosquitoes (Plasmodium parasite). Kala-azar (visceral leishmaniasis) is transmitted by sandflies (Leishmania parasite). Both are vector-borne diseases controllable through vector management. Measles is airborne, cholera and dysentery are water/food-borne.

Malaria is caused by Plasmodium parasites, with P. falciparum being the most severe species. African sleeping sickness is caused by Trypanosoma brucei gambiense (west African) or T. b. rhodesiense (east African). The term 'respectively' means the first organism matches the first disease, and the second matches the second disease.

Ronald Ross discovered in 1897 that malaria is transmitted by female Anopheles mosquitoes. He won the Nobel Prize in 1902 for this discovery. The other scientists listed made discoveries in different fields (X-rays, microbiology, radioactivity).

HIV is pathogenic and causes AIDS.

Female Aedes mosquito acts as a carrier of dengue.

Frequent defecation, with feces usually containing high fluid material is known as Diarrhoea.

Female anopheles mosquito is the vector that carries plasmodium.

This option is correct because contagious 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. Ringworm is a contagious fungal infection caused by mold-like parasites that live on the cells in the outer layer of the skin and leprosy is a contagious disease caused by the bacterium Mycobacterium leprae, but is not easily transmitted.

This option is correct because Elephantiasis or Filariasis is a vector-borne helminthic disease (caused by Wuchereria bancrofti) transmitted by female Culex mosquito.

This option is correct because all are correctly matched.

Aedes aegypti is the primary vector of the dengue virus. Glossina palpalis is the main vector of African sleeping sickness. Filariasis is transmitted by female culex mosquito. Kala-azar is transmitted by Phlebotomus argentipes.

This option is correct because Aedes aegypti is a mosquito that can spread the dengue fever, chikungunya and yellow fever viruses, etc.

This option is correct because all are helminthic diseases. Ascariasis is an infection caused by Ascaris lumbricoides, giant roundworm of humans belonging to the phylum Nematoda. Ancylostomiasis is the condition of infection by Ancylostoma hookworms. Enterobiasis (pinworm infection) is caused by a small, thin, white roundworm called Enterobius vermicularis. Wuchereria bancrofti is a human parasitic roundworm that is the major cause of filariasis.

This option is correct because all the diseases are caused by protozoa. Balantidiasis is a protozoan infection caused by Balantidium coli. Malaria parasites belong to the genus Plasmodium (protozoan). Kala-azar (leishmaniasis) is caused by Leishmania donovani (protozoan). Giardiasis is caused by microscopic protozoan parasites known as Giardia intestinalis.

Malaria is caused by Plasmodium falciparum (a protozoan) transmitted by mosquitoes. African sleeping sickness is caused by Trypanosoma gambiense, also a protozoan transmitted by the tse-tse fly.

Typhoid is correctly matched with Salmonella, its bacterial causative agent. Dysentery is caused by Entamoeba (not Plasmodium), malaria is caused by Plasmodium (not Entamoeba), and tuberculosis is caused by Mycobacterium tuberculosis (not Trypanosoma, which causes sleeping sickness). Option C is the only correct match.