Disease Vectors and Pathogens

Giardia is an infection of i small intestine. causes diarrhoea.

African sleeping sickness is a disease which is caused by a parasite which is a protozoa known as Trypanosoma brucei. There are certain flies which get infected by this protozoan. When the infected fly bites the human, there is transmission of the diseases. The fly is native to Africa and hence, the disease is known as African sleeping sickness. 

Trypanosomiasis is a term which describes various diseases which affect men and cattle. While Trypanosoma gambiense is the milder form, Trypanosoma rhodesiense is one which afflicts more. This deadly parasitic infection is commonly called as sleeping sickness, is transmitted in man by the bite of the infected Tsetse fly of genus Glossina and family Glossinidae that inhabits the mid continental Africa between Sahara and Kalahari deserts.

Kala azar is a parasitic disease next to malaria but along with sleeping sickness this is one of the dangerously neglected diseases of the tropical belt. This disease which is endemic in more than 60 countries attacks the immune system making it nearly fatal.  his disease is transmitted to human beings by the bites of infected phlebotomine sandflies which is the vector for  the leishmania parasite. so, the correct answer is option A.

Sleeping sickness is transmitted by Tse-tse fly. Leprosy is an ailment of the skin and housefly can spread the causative agent. Dysentery can be spread by housefly when they sit on infected materials like stool and contaminate water as well as food. Typhoid is caused by bacteria, housefly can spread it when infected sputum and clothes are infested with houseflies and contaminate food and water. So, the correct answer is option D.

Gambian fever or Gambian sleeping sickness is caused by a protozoan Trypanosoma gambiense and is transmitted by Glossina palpalis (tse-tse fly).

Trypanosoma gambiense causes sleeping sickness and is transmitted by tse-tse fly. Leishmania donovani (please note the spelling) causes kala-azar and is transmitted by Sand fly. Plasmodium falciparum causes malaria and is transmitted by the female anopheles mosquito. Wuchereria bancrofti causes elephantiasis and is transmitted by culex mosquito. So, the correct answer is option C.

Vector host is an agent that transmits the pathogens of infectious disease from one living organism to another and may be a person, animal or microorganism. While the Anopheles mosquito is the vector for malarial parasites, sandfly is a vector for leishmaniasis, tsetse fly are vectors of trypanosomes that causes trypanosomiasis or sleeping sickness. Houseflies on the other hand are vector for nearly 100 pathogens that causes, typhoid, cholera, salmonellosis, tuberculosis, anthrax etc., eer flies which belong to the genus Chrysops are vectors for pathogens that causes diseases such as anthrax, tularemia and loa loa filariasis.

• Amoebiasis or amoebic dysentery is an infection caused by any of the amoebae of the Entamoeba group( For example, Entamoeba histolytica).
• Symptoms may include abdominal pain, diarrhea, or bloody diarrhea.
  
• In the feces of a person suffering from Amoebiasis Small white stone-like Charcot-Leydon crystals are found. They are indicative of a disease involving eosinophilic inflammation or proliferation.
• So, the correct answer is 'Amoebiasis',

Plasmodium is the odd one as it is a digenetic endoparasite with the man as the primary host and female Anopheles mosquito as the vector. While lice, bedbug, and mites all are blood-sucking ectoparasites. Thus the correct answer is option B.

• Sleeping sickness is caused by a parasitic flagellate protozoan called Trypanosoma ambience.
• The disease is transmitted between mammals hist by Tsetse fly
• Fever, severe headaches, irritability, extreme fatigue, swollen lymph nodes, and aching muscles and joints are common symptoms of sleeping sickness.
• Hence The disease caused by Trypanosoma ambience is Sleeping sickness.
  
• So, the correct answer is 'Sleeping sickness'.

Entamoeba histolytica belongs to genus Entamoeba. It frequently exists in the human gastrointestinal tract, infecting the walls of the small intestine. It causes amoeboic dysentery  in  humans.