Malaria Flashcards
My parasitology professor was Dr. James B. Jensen (who almost won the nobel-prize for his work on malaria! Google it- I don’t care..). He had a phrase that he liked to use: “There are 4 kinds of malaria. One of them will kill you, and the other three will make you wish you were dead.” Which is the kind that will kill you?
A. Plasmodium falciparum
B. Plasmodium vivax
C. Plasmodium ovale
D. Plasmodium malariae
A
There is now a fifth kind of malaria that has jumped into the human species and is a killer (faster than falcip, even!) It is seen the the Malaysia/Indonesia area and is Plasmodium knowlesi
Which mosquito is responsible for transmission of the malaria parasite?
A. Aedes sp. B. Culex sp. C. Toxorhynchites sp. D. Anopheles sp.
D
Anopheles spp. mosquitoes capable of carrying/transmitting malaria are currently found in the U.S.:
A. This is true
B. This is false
C. This used to be true, but the species of Anopheles which used to transmit malaria in the U.S. have been eradicated from this country
D. This is false all around. Anopheles spp. do not transmit malaria
A. Of the species of Anopheles mosquitoes found in the United States, the three species that were responsible for malaria transmission prior to elimination (Anopheles quadrimaculatus in the east, An. freeborni in the west, and An. albimanus in the Caribbean) are still widely prevalent; thus there is a constant risk that malaria could be reintroduced in the United States.
In today’s day and age, how many cases of malaria are seen in the U.S. every year?
A. 2000 cases
C. On average, 1,500 cases of malaria are reported every year in the United States, even though malaria has been eliminated from this country since the early 1950’s.
Sure, malaria is important, but just how important is it? You have a patient who has just returned from overseas who has a fever. What should be the FIRST diagnosis you consider?
A. Acute respiratory infection
B. Viral hemorrhagic fever
C. Diarrheal fever
D. Malaria
D. Owing to the prevalence, the increased and ever changing/adapting resistance patterns, and the sheer danger of malaria. MALARIA PATIENTS CAN GO SOUTH (AS IN DOWN THE DRAIN, TO THE GRAVE, BOX, ETC… ) WITH REMARKABLE RAPIDITY!!! DO NOT MISS IT! Symptoms include fever and flu-like illness, including shaking chills, headache, muscle aches, and tiredness. Nausea, vomiting, and diarrhea may also occur. Malaria may cause anemia and jaundice. If not promptly treated, the infection can become severe and may cause kidney failure, seizures, mental confusion, coma, and death.
A patient comes to your clinic with a fever. After spending the year with me, I manage to beat into your head that you should always rule out malaria in patients with a fever because it can be life-saving, and because ruling out the disease can be done so quickly (with only one, quick question). You go ahead and ask that one, quick question: “Have you ever left the country?” His answer is: “I was in Africa about a year ago.” What is your thought process now? Has malaria been ruled out?
A. No. Malaria can present this late after returning from abroad. Do the proper malaria work up.
B. Yes. Unless this guy is either lying, or EXTREMELY unlucky, malaria will not present after 6 months of return from travel.
C. It depends on where he was in Africa (East vs West Africa)
D. This could be an abnormal presentation of TB….
A. For most people, symptoms begin 10 days to 4 weeks after infection, although a person may feel ill as early as 7 days or as late as 1 year later. Two kinds of malaria, P. vivax and P. ovale, can occur again (relapsing malaria). In P. vivax and P. ovale infections, some parasites can remain dormant in the liver for several months up to about 4 years after a person is bitten by an infected mosquito. When these parasites come out of hibernation and begin invading red blood cells (“relapse”), the person will become sick.
You are suspicious of a malarial infection. How can you test for the presence of Plasmodium sp.?
A. ELISA testing
B. PCR
C. GIEMSA staining
D. All of the above
D. PCR is the best (but most expensive and slower), ELISA is the fastest, Giemsa is the old classic. The gift that keeps on giving. I hear some really awesome PA students spent a lot of time reading Giemsa stains…
When do the mosquitoes that cause malaria bite?
A. Daytime
B. Nighttime
C. Dawn/Dusk hours
D. No pattern has ever been found
B
Chloe (yes, Chloe!) comes to your office. She is 4 months pregnant, and wants to take a 2-week trip to a country where malaria transmission occurs. What is your recommendation?
A. Double-coverage of anti-malarial prophylaxis prior to, during, and after travel
B. Recommendation is to NOT travel to a malaria-endemic region while pregnant because pregnancy poses an increased risk.
C. Coverage with the normal anti-malarial prophylaxis. Pregnancy, contrary to what one would think, actually DECREASES malaria risk.
D. Coverage with a normal anti-malarial prophylaxis, but cut the trip to under 10 days, to prevent risk of infection.
B. CDC advises women who are pregnant or likely to become pregnant not to travel to areas where malaria transmission occurs, if possible. Malaria in pregnant women can be more severe than in women who are not pregnant. Malaria can increase the risk for serious pregnancy problems, including prematurity, miscarriage, and stillbirth. If travel to a malarious area cannot be postponed, use of an effective chemoprophylaxis regimen is essential. However, no preventive drugs are completely effective. Please consider these risks (and other health risks as well) and discuss them with your health-care provider.
Certain malaria species prefer to infect immature RBCs (reticulocytes), which are slightly larger than mature RBCs. This gives the cells that are infected a larger, macrocytic look. Which species of Plasmodium prefer the reticulocytes, and therefore are associated with infected cells that are slightly larger?
A. Falciparum and Vivax
B. Ovale and Malariae
C. Falciparum and Ovale
D. Vivax and Ovale
Vivax and Ovale
When evaluating a malaria blood smear, among the first things done is to determine the size of infected cells. Determining the possible presence of Falciparum malaria is of paramount importance. Falciparum will present with normocytic-infected cells.
Why is malaria sometimes called “Blackwater fever”?
A. It isn’t. Blackwater fever refers to another disease
B. It is in reference to the rivers, which provided water for mosquito-breeding, and brought death to villages
C. It refers to a complication of malaria in which severe hemolysis leads to vast amounts of hemoglobin in the urine, creating a very dark urine
D. It is an historical homage to a string of villages that were completely decimated by malaria in the days before malaria was understood
C
You have a patient in whom you suspect a possible malarial infection. Owing to the severity of malaria, you want the test to be as sensitive as possible. This being the case, which of the following is the most important?
A. The thick smear
B. The thin smear
C. Both are needed, one without the other is incomplete
D. The are equally important for sensitivity
A. Speciation can not be done on the thick smear, but with a greater blood volume, the lower levels of parasitemia are more likely to be detected.
Your pt. has been diagnosed with Plasmodium vivax malaria. You now know that vivax is one of the species which can produce hypnozoites, which cause the ‘dormant liver stage’ (you’re welcome!). As you continue to read the lab report, you notice that you are being muscled out of the way. (The word has gotten out that there is a ‘malaria patient’ in the building and suddenly everyone rushes to the scene. Real life, people…) The case is now being headed up by some smug, self-serving, resident who doesn’t know his burro from a burrow. You sigh as you recognize that the resident knows MUCH less about malaria than you do (you’re welcome, again). The resident also recognizes that you are more versed in malaria than he is, and asks what you would recommend to do to prevent relapses from the dormant liver stages. What is your response?
A. No measures are needed beyond regular treatment
B. Get a lab test to determine if the patient has dormant liver stages
C. Treat immediately with Primaquine
D. Order a G6PD test, followed by treatment with Primaquine
E. Go suck on a lemon. I’m out!
D. You should exclude G6PD deficiency first, then give the patient primaquine, 30 mg per day for 14 days.
In case of G6PD deficiency, consultation with an expert in infectious diseases or tropical medicine is advised to discuss options for relapse prevention. For some patients with partial G6PD deficiency, an alternative regimen of primaquine 45 mg weekly for 8 weeks can sometime be used. Alternatively, weekly chloroquine prophylaxis may also be considered. Treatment with primaquine is justified because this patient probably has already had a relapse, and is at risk for further relapses. No test exists to detect the presence of liver stage parasites.
A type and screen is ordered for your newest patient. When the report comes back, you note that the patient lacks the Duffy antigen. With regards to malaria, what does this mean?
A. This patient is at an increased risk of all malaria species
B. This patient is at an increased risk of Plasmodium vivax
C. This patient is unable to be infected with (protected from) Plasmodium vivax
D. This doesn’t mean a darn thing. I’m just blowing smoke.
C. Lack of Duffy antigen: No place for P. vivax to attach and invade. (Turns out this is also true of P. knowlesi!) Consider that the Duffy antigen is almost completely non-existent in black people of African descent. Interesting, no? (Malaria has shaped the human genome in many ways – this is just one example. Consider Sickle Cell anemia, and G6PD for a few other quick-referenced ways…)
A patient comes to you after having spent 4 months in Africa. He says that he never took his anti-malarial prophylaxis because “it’s just not my style”. He indicates that he has had a fever every 4th day for the last couple of weeks. You quiz him, and yes- he is sure- it is every 4th day. “Like clockwork,” he says.
How concerned are you?
A. Very. The severity of malaria cannot be overstated
B. Extremely. He needs to be admitted right away.
C. Only moderately. This is likely a case of Plasmodium malariae. You will need to be sure, but for now- you relax slightly.
D. Either A or B are correct responses
C
