10.12.18 Malaria

Question 1

Obligate intracellular eukaryotic parasite

Asexual/sexual life cycle

Answer 1

Malaria

Question 2

Do female or male anopheles sp. mosqutos take blood meals?

Answer 2

Female

Question 3

What is the Malaria lifecycle?

Answer 3

1. Sporozoites go to liver is where it starts
2. Prepatent period where you don’t know you’re infected
3. Infected RBC do asexual reproduction (Tropozoite- mezazoite- gametocyte)
4. Gametocyte formation is the transmissable stage

Question 4

What is the cause of malaria?

Answer 4

Plasmodium

Question 5

Patient is asymptomatic while parasite multiplies in liver (7-14 days)

Answer 5

Prepatent period

Question 6

Shaking chills, high fever, bursting RBC to make merozoites

Headache, nausea, vomiting, malaise

Answer 6

Paroxysm

Question 7

What is sever malaria almost always due to and what are its clinical manifestations?

Answer 7

Falciparum malaria

1. Cerebral malaria
2. Severe anemia
3. Multi-organ failure

Question 8

What are the 3 ways in which malaria kills children?

Answer 8

1. Infection in pregnancy- low birth weight, preterm delivery
2. Acute febrile illness- cerebral malaria, respiratory distress, hypoglycemia
3. Chronic repeated infections- severe anemia

Question 9

What is the difference between falciparum malaria in a low immunity areas vs. high immunity areas?

Answer 9

Low:

• Bites rare
• Adults not immune
• Malaria causes sig. disease in adults and children

High:

• High bites
• Adults semi-immune- but short lived w/o continued exposure
• Adults: asymptomatic/miled
• Children: seriously ill

Question 10

What causes a genetic resistance to malaria?

Answer 10

1. Sickle cell trait
2. Thalassemia
3. G6PDH deficiency

Question 11

Resistance due to lack of Duffy Antigen in persons of African descent; Relapse due to dormant liver stage

Answer 11

Vivax malaria

Question 12

How can you diagnose malaria?

Answer 12

1. Blood smear
2. Rapid Diagnostic Tests
3. PCR

Question 13

What biologic characteric makes Plasmodium falciparum the malaria species most likely to cause severe disease?

Answer 13

The ability to sequester in the microvasculature

Question 14

How is malaria controlled?

Answer 14

1. Insectiside Treated Bed nets (ITNs) - used with poor infrastructure
2. Indoor Residual Spraying (IRS) - DDT w/ good infrastructure
3. Chemotheraphy

Question 15

How is malaria treated?

Answer 15

Started with quinine, then chlorquine/mefloquine, then SP (Fansidar) then Artemisinin combination therapy (Coartem)

Question 16

What is the global standard for Falciparum malaria treatment?

Answer 16

Artemisinin combination therapy (ACT)

Question 17

What chemotherapy shouldbe used with Vivax?

Answer 17

Chloroquine

Use ACT where chloroquine resistance exists

Question 18

How should travelers prevent malaria?

Answer 18

1. Insect repellant
2. Long sleeves/pants
3. Avoid outdoors during peak biting times
4. Prophylaxis