Malaria Flashcards
1
Q
Malaria organism
A
Plasmodium protozoa
- P. falciparum (most severe)
- P. vivax
- P. ovale
- P. malariae
- P. knowlesi
2
Q
Malaria vector
A
female Anopheles mosquito
3
Q
MC way to acquire malaria
A
mosquito bite in endemic area (tropical and subtropical areas)
4
Q
High risk groups for malaria infection
A
- young children
- pregnant women
- travelers/migrants
5
Q
Is malaria in the US??
A
- 1,700 cases a year
- Anopheles mosquito is in the US
- risk of resurgence
6
Q
4 ways Malaria is transmitted
A
- bite from female Anopheles mosquito (MC)
- Airport malaria: mosquito on plane from endemic to non endemic area
- Congenital
- Transfusion (rare in US)
7
Q
Pathophysiology
A
- two hosts: mosquito and human
- Anopheles transmits plasmodia (in saliva) into host when bite
- In human, parasite grow and multiply in liver and then RBC
- in RBC, grow and destroy cells, release merozoites which invade other RBC
- RBC cytolysis = release toxic metabolites = flulike sx for host
- Some differentiate into gametocytes which are ingested by another Anopheles, grow and multiply into new sporozoites and get into saliva, start cycle over
8
Q
P. Falciparum
A
- Most severe
- microvascular effects
- only type can cause death if untx
9
Q
P. vivax
A
- Most West Africans have resistance dt lack of Duffy blood group on RBC so plasmodium cannot attach
- generally causes less severe dz
10
Q
P. ovale
A
Less common
- tertian pattern of fever: q 48 hour spikes
11
Q
P. Malariae
A
- may cause no acute sx
- can lead to immune mediated nephritic or nephrotic syndomre
- fever quartan pattern q 72 hours
12
Q
P. knowlesi
A
- SE asia
- Monkey is intermediate **
- rare but can cause dz in humans
13
Q
Incubation
A
- approx 4 weeks
- vivax and ovale: weeks to months after initial infection, hypnozoite form (can linger in liver longer). Have to treat this stage separately
- shorter incubation falciparum
- longer incubation malariae
14
Q
common S/sx
A
- HA
- fever, shaking chills, sweats (q48-72 hr depending on species)
- cough
- fatigue
- malaise
- arthralgia
- myalgia
15
Q
less common s/sx
A
- anorexia/lethargy
- n/v
- diarrhea
- jaundice
16
Q
PE
A
- splenic/liver enlargement
- fever
- mild jaundice
- cerebral malaria (coma?)
- anemia
- resp abnl
- renal failure
- no rash or lymphadenopathy
17
Q
Dx
- general tests
A
- history!! Travel
- Labs: blood culture, CBC, iron panel, CMP, liver/renal fn tests, electrolytes, LDH
- CXR if resp sx
- CT if CNS sx
18
Q
Dx
- malaria specific tests
A
- Giemsa stained peripheral blood smear. multiple smears needed
- Rapid dx tests via dipstick
- PCR assay (to confirm after blood smear)
19
Q
ABCDs of malaria
A
- Awareness: recognize malaraia
- Bite prevention: control mosquitoes, use a net
- Chemo prophylaxis: use preventative meds
- Dx: early recognition
20
Q
Malaria prevention
A
- long clothing to reduce exposed skin (esp dusk to dawn)
- topical repellants
- other repellants
- no chemoprophylaxis regime = 100% protection!!
