African animal trypanosomosis (AAT)

Context: Recently Ethiopia has released the first edition of an atlas to map Tsetse and Trypanosomosis affecting livestock in the country and the vector behind it.

About ATT:

• Also known as nagana or nagana pest, Animal African Trypanosomosis (AAT), is a protozoan parasitic disease of vertebrate animals.
• It affects cattle, water buffalo, sheep, goats, horses, pigs, dogs and other species.
• The disease is caused by the protozoan parasites Trypanosoma congolense, Trypanosoma vivax and, to a lesser extent, Trypanosoma brucei brucei which are all mainly transmitted by tsetse flies.
• Distribution: From the southern edge of the Sahara desert to Zimbabwe, Angola and Mozambique in the South.
• Impact: Animal African Trypanosomosis (AAT) is estimated to kill 3 million cattle annually.
  • Losses directly attributed to trypanosomosis from reduced meat and milk production, and the cost of treatment and vector control, are estimated to be USD $1.2 billion.
  • Losses in agricultural gross domestic product for all tsetse-infested lands was estimated to be USD4.75 billion per annum.
• Epidemiology: Most trypanosomes develop for one to a few weeks in tsetse flies (Glossina spp.), which act as biological vectors.
  • The parasites are transmitted to the host animal in saliva when a fly bites the host.
  • Trypanosomes can also be spread by fomites such as surgical instruments and mechanical vectors like biting flies including horse flies—especially T. vivax.
• Trypanosomes infect the blood of the host causing fever, weakness, lethargy and anaemia, which lead to weight loss and a reduction in fertility and milk production.
• Control: AAT can be controlled by reducing tsetse fly populations with traps and insecticides.
  • Animals can be given antiparasitic drugs prophylactically in areas with a high population of trypanosome-infected tsetse flies.
  • No vaccine is available to prevent trypanosomiasis.

Source:  DownToEarth

Previous Year Questions

Q.1) Which one of the following statements best describes the role of B cells and T cells in the human body? (2022)

1. They protect the body from environmental allergens.
2. They alleviate the body’s pain and inflammation.
3. They act as immunosuppressants in the body.
4. They protect the body from the diseases caused by pathogens.

Q.2) With reference to recent developments regarding ‘Recombinant vector Vaccines’, consider the following statements:

1. Genetic engineering is applied in the development of these vaccines.
2. Bacteria and viruses are used as vectors.

Which of the statements given above is/are correct? (2021)

1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2