Lect 28

Question 1

List the important species that cause malaria

Answer 1

• plasmodium vivax
• p. falciparum
• p. malariae
• p. ovale
• p. knowlesi

Question 2

malaria lifecycle is complex and has a phase and a phase

Answer 2

• human phase
• mosquito phase

Question 3

malaria process in humans in initiated by the injection of plasmodium through transmission of mosquito saliva during a bloodmeal

Answer 3

sporozoites (motile forms)

Question 4

​sporozoites migrate to the and asexual division known as the cycle begins

Answer 4

• liver
• schizogony

Question 5

life cycle form released from the schizogony cycle in the liver are called

Answer 5

Merozoites

Question 6

​Merozoites can infect other liver cells or and start the cycle

Answer 6

• RBC
• Erythrocytic cycle

Question 7

Once in an RBC, ​Merozoite enlarges and undergoes a differentiation into a cell termed a

Answer 7

• Ring trophozoite
  
  • ​one nucleus

Question 8

as Ring trophozoite age, they can develop into

Answer 8

• amoeboid trophozoites

Question 9

single nucleus of a Ring trophozoite can divide to produce a multinucleated form called a

Answer 9

schizont

Question 10

erythrocytic ​schizonts are multinucleated cells that produce

Answer 10

erythrocytic merozoites

Question 11

When happens to erythrocytic merozoites, when the RBC it is in ruptures

Answer 11

• merozoites escape to invade new cells
  
  • schizogony can begin again
  • or gametogony is initiated

Question 12

sexual cycle of malaria is known as ? Can complete sexual cycle occur in humans?

Answer 12

gametogony

• merozoites in erythrocytes can develop into gametocytes
  
  • do not cause cell rupture
• mosqito feeds and takes in gametes -> sexual reproduction requires mosquito

Question 13

malaria organisms consume

Answer 13

hemoglobin

Question 14

fever and chills correspond to release of following rupture of RBC which travels to hypothalamus and causes an increased thermal set point

Answer 14

pyrogen

Question 15

list the natural based immunity to malaria

Answer 15

1. sickle cells anemia produces resistance to falciparum malaria
2. lack of or resistance to duffy antigen - a receptor for P. vivax

Question 16

reservoirs for malaria

Answer 16

• humans
• simians

Question 17

vector for malaria

Answer 17

• several species of the night feeding anopheline mosquito

Question 18

Plasmodium vivax infects what type of RBCs

Answer 18

young erythrocytes

Question 19

Plasmodium vivax causes what condition

Answer 19

benign tertian malaria

Question 20

fever and chills associated with Plasmodium vivax is due to

Answer 20

rupture of RBC schizonts

Question 21

Plasmodium vivax is capable of

Answer 21

• relapses
  
  • occur as result of activation of liver hyponozoites
  • can be 3-5 years after initial disease

Question 22

reservoir for Plasmodium vivax

Answer 22

human only

Question 23

where is Plasmodium vivax mostly found

Answer 23

• tropics

Question 24

how is Plasmodium vivax identified

Answer 24

• giemsa stain on venous blood
  
  • enlarged infected RBCs with schuffner’s dots (surface invaginations)

Question 25

**Plasmodium falciparum** causes **high grade parasitemia** which can lead to what condition

Answer 25

* blackwater fever * high levels of hemoglobin in urine -\> dark to black urine

Question 26

malignant tertian malaria is caused by

Answer 26

Plasmodium falciparum

Question 27

Plasmodium falciparum can lead to capillary obstruction as infected RBCs stick to capillary linings which causes what 3 conditions

Answer 27

* cerebral malaria * gastric falciparum malaria * algid malaria: skin is cold even with fever

Question 28

can relapses occur with Plasmodium falciparum

Answer 28

* no * no hyponozoite stage

Question 29

how is Plasmodium falciparum identified

Answer 29

* erythrocytes with **_double or multiple ring stages_**, **Maurer's cleft**

Question 30

what stages of Plasmodium falciparum can be observed in peripheral smeal

Answer 30

* trophozoites * gametocytes * \*\*not schizonts

Question 31

Plasmodium malariae infects what type of RBC

Answer 31

older erythrocytes

Question 32

reservoir for Plasmodium malariae

Answer 32

* primate - zoonotic

Question 33

how is Plasmodium malariae identified

Answer 33

* trophozoites (basket and band shaped) * schizonts (rosette shaped)

Question 34

What is the causative agent of Babesiosis, or Nantucket island fever

Answer 34

Babesia microti

Question 35

how is Babesia microti identified

Answer 35

forms **cross-like** morphology on **RBC**

Question 36

Babesia microti * infects what type of cells * prevalent in * vector

Answer 36

* RBC * New England * Deer tick

Question 37

vector for Chaga's disease

Answer 37

Triatomine bugs "kissing bugs"

Question 38

Chagas disease is caused by

Answer 38

Trypanosoma cruzi

Question 39

how is Chagas disease transmitted

Answer 39

* feces of Trypanosoma cruzi

Question 40

Chagas disease has an acute and chronic stage. What is characteristic sign of acute phase

Answer 40

* chagoma * Romana's sign * swelling of eyelid near the parasite entry site

Question 41

how is Chagas disease diagnosed

Answer 41

* e**xtracellular** * **​observe parasite under microscopy in _acute_ phase**