E2- Malaria and Basesiosis

Question 1

What are the 5 important species of Malaria?

Answer 1

Plasmodium vivax
P. falciparum
P. malariae
P. ovale
P. knowlesi

Question 2

What initiates the malaria process in humans?

Answer 2

Injection of Plasmodium sporozoites (motile forms) through transmission of mosquito saliva during a bloodmeal

Question 3

What migrates to the liver in the bloodstream where they undergo asexual division?

Answer 3

Sporozoites

Question 4

What is asexual division of sporozoites called?

Answer 4

Schhizogony

Question 5

What is a vaccine target for malaria?

Answer 5

Sporozoites

Question 6

What form of malaria can enter RBCs?

Answer 6

Merozoites

Question 7

Once in RBCs, merozoites enlarge and undergo differentiation to a uninucleate cell. What is this cell called?

Answer 7

Ring trophozoite

Question 8

As trophozoites age, what can they develop into?

Answer 8

Amoeboid throphozoites

Question 9

What is a multinucleated cell that produce erythrocytic merozoites called?

Answer 9

Erythrocytic Schizont

Question 10

What do erythrocytic schizonts produce?

Answer 10

Erythrocytic Merozoites

Question 11

What occurs after infected RBCs rupture and merozoites escape?

Answer 11

They invade new cells and schizogony begins again or gametogony (sexual cycle) is . initiated

Question 12

Some merozoites in erythrocytes develop into ____ and do not cause the erythrocyte to rupture?

Answer 12

Gemetocytes

Question 13

What do malarian organisms consume?

Answer 13

Hemoglobin

Question 14

What occurs in response to the release of pyrogenic waste following rupture of RBCs schizonts?

Answer 14

Fever and chills

Question 15

What travels to the hypothalamus and causes an increased thermal set point?

Answer 15

Pyrogen

Question 16

The release of what intensifies the symptoms of malaria?

Answer 16

Tumor necrosis factor (TNF)

Question 17

What are some possible symptoms of malaria?

Answer 17

Fever, shivering 
N/V 
Diarrhea
Anemia (RBC destruction)
Hypotension (vasodilation)

Question 18

What disease produces resistance to malaria?

Answer 18

Sickle cell anemia (parasite has difficulty utilizing abnormal hg)

Question 19

How are many African Americans and West Africian black person resistance to vivax malaria?

Answer 19

Many lack the duffy antigen, which is a receptor for P. vivax merozoites

Question 20

What vaccine is available for malaria?

Answer 20

RTS, S (Mosquirix)

Question 21

What types of malaria is the RTS, S (Mosquirix) vaccine effective against?

Answer 21

P. falciparum

Question 22

What does the RTS, S (Mosquirix) vaccine target?

Answer 22

Sporozoites

Question 23

What are some limitation to the RTS, S (Mosquirix) vaccine?

Answer 23

Requires 4 injections
Low efficacy
5 yr half-life (requires half-life)
Expensive

Question 24

What species of mosquito is a vector for malaria?

Answer 24

Anopheline mosquito (female)

Question 25

Is there such thing as a carrier state in maleria?

Answer 25

Yes (tolerant carriers contribute to spread)

Question 26

What may contribute to an increase in malaria cases in the next 50 yrs? Why?

Answer 26

Climate change New areas exposed to Plasmodium No host resistance developed

Question 27

What are majority of malaria cases in the US linked to? | What forms of malaria are majority of the cases?

Answer 27

Travel to Africa | 60% falciparum, 20% vivax

Question 28

What do vivax species tend to infect?

Answer 28

Young erythrocytes (not many RBCs infected)

Question 29

Patient presents with chills and shaking 10-15 minutes, with increased sweating, anemia, headche, back pain, myalgia, nausea, vomiting, diarrhea and cough. What form of malaria do you suspect?

Answer 29

P. vivax

Question 30

Relapses of P. vivax infection can result from what?

Answer 30

Activation of liver hypnozoites (can be 3-5 yrs after initial disease)

Question 31

What stain is used to ID P. vivax?

Answer 31

Venous blood processed with | Giemsa stain

Question 32

What will a Giemsa stain of venous blood show in a . P. vivax infection?

Answer 32

Enlarged infected RBCs with Schuffner's dots (surface invaginations and stipling)

Question 33

What form of malaria is virulent and causes high grade parasitemia because RBCs of any age are infected?

Answer 33

Plasmodium falciparum

Question 34

What form of malaria can lead to Blackwater fever? What causes this?

Answer 34

Plasmodium falciparum | High parasite numbers

Question 35

What is Blackwater fever?

Answer 35

High levels of free hemoglobin in urine Leads to autoimmune reaction in which the host destroys kidney tissue Chills, fever, rigor, dark to black urine

Question 36

How does Falciparum malaria lead to capillary obstruction?

Answer 36

Infected RBCs tend to stick to capillary linings

Question 37

What can capillary obstruction associated with Falciparum malaria cause?

Answer 37

Cerebral malaria Gastric falciparum malaria Algid malaria

Question 38

What does cerebral malaria cause?

Answer 38

Necrosis, hemorrhages, extreme fever, mania, convulsions and death

Question 39

What does gastric falciparum malaria cause?

Answer 39

Frequent vomiting in addition to other symptoms

Question 40

What does algid malaria cause?

Answer 40

Skin is cold but internal temperature is high

Question 41

Can Plasmodium falciparum relapse? Why?

Answer 41

No, no hypnozoite stage

Question 42

How is Plasmodium falciparum identified?

Answer 42

Erythrocytes with double or multiple ring stages Crescent shaped gametocyte Mauerer's clefts Many infected cells

Question 43

In a Plasmodium falciparum infection, young trophozoites and gametocytes are seen in the periphery, but what is not seen?

Answer 43

Not schizonts

Question 44

Which form of malaria is more virulent?

Answer 44

Plasmodium falciparum

Question 45

What form of malaria infects older erythrocytes, has paroxysms every 4th day, and has zoonotic from primate reservoirs?

Answer 45

Plasmodium malariae

Question 46

How is Plasmodium malariae identified?

Answer 46

Trophozoites (basket and band shaped) and schizonts (rosette shaped)

Question 47

What form of malaria is similar to vivax malaria, has common relapses, and is common to the west coast of Africa?

Answer 47

Plasmodium ovale

Question 48

What form of malaria is zoonotic, maybe life-threatening if a heavy parasite burden occurs, and is usually found in Southeast Asia?

Answer 48

Plasmodium knowlesi

Question 49

Why is the incidence of vivax malaria increasing in Africa?

Answer 49

Organism increasingly independent of binding to Duffy antigen

Question 50

What is the main mechanism of malaria multidrug resistance?

Answer 50

Efflux pumps (more expensive to treat)

Question 51

What is the causative agent of . Babesiosis, or Nantucket Island Fever?

Answer 51

Babesia microti

Question 52

There is increasing issues of transmition of Babesia microti through what?

Answer 52

Blood donation

Question 53

What is the vector for Babesia microti?

Answer 53

Deer tick

Question 54

Patient presents with malaria like symptoms with small pinpoint lesions and later becomes anemic. What do you suspect?

Answer 54

Babesia microti

Question 55

What type of malaria is Babesia microti most similar to?

Answer 55

Plasmodium falciparum (but less severe)

Question 56

How is Babesia microti identified?

Answer 56

Cross-like morphology in RBCs