Infectious Dz Exam 3: Malaria (5)

What is the therapy for the eradication of *persistent hypnozoites* in the *liver stages* of P. vivax or P. ovale?

*Primaquine phosphate* (NO alternative therapy available). CHECK G6PD STATUS PRIOR TO INITIATION OF MEDICATION!!!

How long does the *cold stage* last in malaria paroxysm?

15-60 minutes

How long does the *hot stage* last in malaria paroxysm? How long does the *sweating stage last*?

2-6 hours

How severely can P. falciparum decrease Hct?

8-10% in 48 hours !!!

What is the definition of malaria?

An infectious disease characterized by cycles of chills, fever, and sweating, caused by a protozoan of the genus Plasmodium in red blood cells, which is transmitted to humans by the bite of an infected *female anopheles mosquito.*

What MUST be checked before initiating *Primaquine* malaria Tx or Prophylaxis?

Check G-6-PD status

What does the rapid "dipstick test", *BinaxNOW*, identify?

Detects bi-product (LDH) of the parasite malaria. P. falciparum from the other species.

What are the symptoms of malaria? Is everyone symptomatic?

FLULIKE illness: HA, *fever*, fatigue, diarrhea, malaise, mm aches, GI sxs. NOT every infected person is symptomatic. Healthy pts may have a chronic stage of low parasitemia and be asymptomatic with a *mild anemia*.

What is Falciparum so bad?

Falciparum targets ALL RBCs, while other forms only target the reticulocytes..!!!

Which plasmodium species has the longest incubation period? Which has the shortest?

Longest -- P. malariae: 28 days. Shortest -- P. falciparum: 12 days. P. vivax & P. ovale may relapse after longer period...

How should the treatment for Malaria be monitored?

Monitor for... acidosis, seizures, pulmonary edema, renal failure. Control glucose!! The CDC no longer recommends exchange transfusions as of 7/15/2013...!

Is Sickle Cell a protective factor for malaria?

NO!! Sickle cell disease is not a protective factor- in fact malaria is one of the top precipitating factors of a sickle cell crisis. *Sickle Cell TRAIT* (HbAS) can be protective when compared to NO Sickle Cell (HbAA).

Should a patient with cerebral malaria be given steroids?

NO!!!! Steroids make cerebral malaria WORSE..!

Should a malaria patient receive a transfusion?

NO!!!! The CDC no longer recommends exchange transfusions as of 7/15/2013...

Which plasmodium have *48 hour* paroxysm of fever?

P. falciparum (can be sporadic) P. vivax P. ovale

Which plasmodium have *48 hour* paroxysm of fever?

P. falciparum (can be sporadic) P. vivax P. ovale - Not apparent during initial infection. - Seen in long-standing synchronous infections. - Not a reliable clue to the diagnosis of malaria.

Malaria *reinfection* is most common with which species?

P. falciparum (intense transmission)

Which Plasmodium species is found primarily in the tropics and subtropics>

P. falciparum and P. malariae ("patchy" distribution)

Which species of malaria is known to cause a *persistent infection* that is *below detectable levels* for up to 20-30 years!!!??

P. malariae

Which plasmodium has the potention for a prolonged erythrocytic infection (can become symptomatic YEARS later)??

P. malariae - NO hypnozoite stage - can be asymptomatic

Which plasmodium has a *72 hour* paroxysm of fever?

P. malariae - Not apparent during initial infection. - Seen in long-standing synchronous infections. - Not a reliable clue to the diagnosis of malaria.

What is the incubation period based on species? P. malariae P. ovale P. vivax P. falciparum

P. malariae: 28 days P. ovale: 17 days P. vivax: 14 days P. falciparum: 12 days MOV-F (28, 17, 14, 12) Symptomatic a few weeks after infection ...

Which Plasmodium species is found primarily in tropical *West Africa*?

P. ovale

Plasmodium that is most widespread (found in ALL endemic areas)

P. vivax

Diagnostic labs for malaria -- what does the thick smear ID?

PARASITIC LOAD

Explain *Malaria Paroxysm*

Periodic febrile episodes alternating with symptom-free periods!

How is SEVERE Malria (P. falciparum) treated?

Quinidine gluconate IV plus one of the following: Doxycycline Clindamycin

Malaria *Recrudescence*?

Reoccurence of malaria infection due to INCOMPLETE TREATMENT!!! MC P. falciparum due to *drug resistence*. Partially effective host immune response..

Diagnostic labs for malaria -- what does the thin smear ID?

SPECIES

Microvascular sequestration/disease

malaria!

How long before departure should prophylaxis malaria medications be taken? How long after return?

start 1-2 weeks before departing!!! - 1-2 days if daily regimen. - Continue for 4 weeks after return.

Malaria cases in the U.S. hit a 40 year high in 2011 with approx. 2,000 cases. The two most common places the cases were imported from were ...?

sub-Saharan Africa and India