10-11. Chagas Disease

Question 1

What are the vectors of T. cruzei?

Answer 1

Reduviid or triatominae bugs

Question 2

What is the life cycle of T. cruzei?

Answer 2

Humans infected with metacyclic trypomastigotes
Inside cells, particularly nerve fibre endings of cardiac muscle, they becomes amastigotes
Multiply by binary fission
Intracellular amastgotes become trypomastigotes andante blood stream
Insect ingests trypomastigote form
Epimastigote in mid gut
metacyclic trypomastigotes in hind gut
bug takes a blood meal…

Question 3

What are four routes of transmission of T. cruzei?

Answer 3

1. vector borne
2. transfusion of infected blood
3. congenital: mother to foetus
4. Ingestion of infected sources

Question 4

What occurs in the mild acute form of the disease?

Answer 4

fever
swelling lymph glands
liver and spleen enlargement
Ramana’s sign

Question 5

What occurs in the severe acute form of the disease?

Answer 5

myocarditis

meningoencephalitis

Question 6

What diseases may develop due to chronic life long T. cruzei infection?

Answer 6

Cardiac diseases
Gastrointestinal signs
Cardiomyopathy in 20-30%

Question 7

2 drugs used to treat chagas and when are they effective?

Answer 7

Nifurtimox

Benznidazole

Question 8

Risk factors of chagas disease

Answer 8

Rural to urban migration

Poverty - poor house construction