Term
| This genus contains the parasite responsible for causing malaria |
|
Definition
| Plasmodium, in the class Sporozoa. P. falciparum is the most serious of the group, with P. vivax also causing malaria and P. malariae, ovale, and knowlesi rounding out the group |
|
|
Term
Which phase of the plasmodium life cycle is injected into the human host during the mosquito blood meal?
a) merozoite
b) hypnozoite
c) sporozoite
d) trophozoite |
|
Definition
| c, sporozoites are injected into the human host's blood stream where they travel to the liver and infect hepatocytes |
|
|
Term
| These two species of plasmodium can go into a "dormant" state in liver hepatocytes for months or years before continuing their replication. |
|
Definition
| P. vivax and P. ovale can both enter into a hypnozoite stage and cause relapses of disease after weeks months or years |
|
|
Term
| This type of schizogony takes place outside the erythrocyte, in the liver. |
|
Definition
| Exo-erythrocytic schizogony, the merozoites go on to infect erythrocytes |
|
|
Term
| This erythrocytic glycoprotein provides the point of entry for the merozoite to the RBC, it is specific to each species of Plasmodium. |
|
Definition
|
|
Term
| This trophozoite is the point of divergence for the asexual and sexual reproductive cycles for Plasmodium |
|
Definition
| Ring trophozoites, can either mature into trophozoites and undergo erythrocytic schizogeny (asexual reproduction), or mature into gametocytes to undergo sexual reproduction |
|
|
Term
| True or false: Gametocytes undergo fertilization in the human host and are then taken up by the Anopheles mosquito to mature |
|
Definition
| False, Gametogeny only takes place in the mosquito. Male plasmodium is taken by a mosquito during a blood meal where they meet the female plasmodium, and fertilizaiton occurs |
|
|
Term
| This cycle takes place in the mosquito, wherein the male and female gametocytes produce zygotes |
|
Definition
|
|
Term
| These motile forms resulting from zygote development invade the midgut lining of the mosquito to form oocysts |
|
Definition
|
|
Term
| These forms, which are the infective form in humans, move from ruptured oocysts into the mosquito's salivary glands |
|
Definition
|
|
Term
| This disease is thought to have killed the most humans worldwide throughout history |
|
Definition
|
|
Term
| About 1500 imported cases, mostly from sub-saharan Africa, of this disease appear in the US every year |
|
Definition
|
|
Term
| This was the first anti-malaria drug introduced in the 1940's, it dramatically reduced deaths due to malaria until resistance developed in the 70's and 80's |
|
Definition
|
|
Term
| What unusual occurrence regarding malaria transmission has taken place in the US since the 80's? |
|
Definition
| Autochthonous cases, or instances where malaria was contracted in the US instead of in other parts of the world and brought here by immigrants |
|
|
Term
| Malaria and what viral STD share a synergistic relationship, increasing the severity of both infections? |
|
Definition
| HIV, complex interplay between acquired immunity and local ecology |
|
|
Term
| What time of day does the female Anopheles mosquito tend to bite? |
|
Definition
|
|
Term
| This stage of infection causes symptomatic disease |
|
Definition
|
|
Term
| What two events contribute to the anemia seen in malaria? |
|
Definition
| Hemolysis from release of merozoites from RBCs and splenic sequestration of infected RBCs |
|
|
Term
| What four pathologic processes make up the clinical signs and symptoms of malaria? |
|
Definition
| Fever, anemia, tissue hypoxia and P. falciparum differentially kills EPO stem cells and exacerbates the anemia |
|
|
Term
| What three factors in the pathogenesis of P. falciparum malaria contribute to metabolic acidosis? |
|
Definition
| Hypovolemia from N/V and sweating, severe anemia, and microvascular obstruction |
|
|
Term
| These forms on the surface of erythrocytes are induced during erythrocyte infection, contributing to endovascular damage, hypoxia and disruption of blood-brain barrier. |
|
Definition
|
|
Term
| In addition to direct endothelial damage and clot formation, what systemic condition occurs as a result of stimulated macrophages secreting tissue factor? |
|
Definition
| DIC, disseminated intravascular coagulation |
|
|
Term
| What four congenital RBC abnormalities confer protection against Pf infection? |
|
Definition
| glucose-6-phosphate dehydrogenase deficiency, pyruvate kinase deficiency, hemoglobinopathies (sickle cell trait), RBC surface protein deficiency (Duffy protein) |
|
|
Term
| Though death from this strain of Plasmodium is uncommon, it is associated with irreversible glomerulonephritis in children in endemic areas. |
|
Definition
|
|
Term
| In ruling out Pf as a cause of malaria, what four clinical signs and symptoms should be examined? |
|
Definition
| How sick is the person, the degree of anemia, incubation period and degree of parasitism, all more severe in Pf infection |
|
|
Term
| This drug is necessary to kill Pv and Po in their hypnozoite form in the liver |
|
Definition
| Primaquine, a derivative of 8-aminoquniolines |
|
|
Term
| In chloroquine and mefloquine resistant areas, what is the preferred prophylaxis for malaria? |
|
Definition
|
|
Term
| In chloroquine-resistant areas, what is the first choice prophylaxis? |
|
Definition
|
|
Term
| Chikungunya virus is a member of this genus of viruses, in the togaviridae family |
|
Definition
|
|
Term
Chikungunya virus is a:
1) double stranded DNA virus
2) single stranded - sense RNA virus
3) single stranded + sense RNA virus
4) double stranded RNA virus |
|
Definition
|
|
Term
| While Chikungunya fever has been reported in travelers world-wide, it is mainly confined to central and south Africa and parts of Asia |
|
Definition
|
|
Term
| These mosquitoes are the vectors for Chikungunya virus |
|
Definition
| Aedes aegypti & Aedes albopictus, the latter mostly in Asia |
|
|
Term
| When does Chikungunya virus transmission peak during the year? |
|
Definition
| During tropical rainy seasons |
|
|
Term
The normal range for Chikungunya virus incubation is:
1) 14-20 days
2) 1-5 days
3) 3-7 days
4) 8-12 |
|
Definition
|
|
Term
| Which cells does the Chikungunya virus tend to infect? |
|
Definition
| Myeloid and lymphoid cells, leading to activation of humoral and cellular immunity |
|
|
Term
| True or false: most Chikungunya viral infections are asymptomatic |
|
Definition
| False, most are symptomatic, headache, malaise arthralgia, myalgia and low back pain, ankles and wrists commonly involved, increased pain with pressure |
|
|
Term
| What four criteria define DHF in addition to the manifestations of dengue fever? |
|
Definition
| Fever of 2-7 days duration, hemorrhagic tendency, thrombocytopenia and evidence of plasma leakage, DSS is added if shock is present along with 4 criteria |
|
|
Term
| By what criteria, respectively, is dengue classified as an arbovirus and a flavivirus? |
|
Definition
| Epidemiologic & antigenic relatedness |
|
|
Term
| This mosquito is responsible for the transmission of Dengue, as well as yellow fever and Chikungunya fever. |
|
Definition
|
|
Term
| In adults, which number re-infection correlates with DHF occurrence? |
|
Definition
|
|
Term
| Compared to adults, what is different about the occurrence of DHF in infants? |
|
Definition
| Tends to happen with the first infection |
|
|
Term
| What genus of virus does the yellow fever virus belong to? |
|
Definition
| flavivirus, 4 different genotypes, 2 in Africa and 2 in South America |
|
|
Term
| Though 200K cases occur across South American and Sub-Saharan Africa, 90% occur in this country |
|
Definition
| Africa, approx. 30K deaths each year |
|
|
Term
| These populations are most susceptible to Yellow Fever in South America |
|
Definition
| Forestry & agricultural workers near forests, as the mosquito tends to live in these areas, and in the savannah of Africa |
|
|
Term
| While humans are the usual Yellow Fever reservoir, in the jungle the virus follows this type of cycle, where non-human primates are the reservoir |
|
Definition
| Sylvatic, transmission among non-human primates facilitated by mosquitoes |
|
|
Term
| What is the primary target organ of the yellow fever virus? |
|
Definition
|
|
Term
| True or false: exposure to other flavivirus confers protection against yellow fever |
|
Definition
| True, neutralizing antibodies post infection or vaccination confer lifelong protection |
|
|
Term
| What is the mortality rate of Yellow Fever cases? |
|
Definition
|
|
Term
| What serologic tests can be done to detect Yellow Fever virus for diagnosis? |
|
Definition
| hemagluttinin, EIA for viral antigen or IgG, IgM antibodies |
|
|
Term
| If given early in the disease course, this drug may have some benefit in treating Yellow Fever |
|
Definition
|
|
Term
| What common trait is shared by Yellow Fever, Plague and Cholera? |
|
Definition
| International quarantine regulations apply to these three illnesses |
|
|
Term
|
Definition
| The species of louse that causes typhus in humans |
|
|
Term
| The causative agents of epidemic typhus |
|
Definition
| Rickettsia prowazekii & Rickettsia parkeri |
|
|
Term
The only other vertebrate reservoir of R. prowazekii is:
1) Horses
2)Sheep
3)Rodents
4)Flying Squirrels
5)none |
|
Definition
|
|
Term
| Contrast the rash of typhus with the rash of Rocky Mountain Spotted Fever |
|
Definition
| RMSF typically appears on the palms, face and soles, while the rash of typhus typically spares these areas and appears over the rest of the body |
|
|
Term
| What is the incubation period of typhus? |
|
Definition
| 1 week, presents with headache, chills, fever and myalgia |
|
|
Term
| What are the sequelae of epidemic typhus? |
|
Definition
| Pneumonia (primary or secondary), encephalitis, vascular collapse, mortality rate up to 40% untreated |
|
|
Term
| This agent is the cause of murine typhus |
|
Definition
|
|
Term
| This is the tx of choice for Murine typhus |
|
Definition
|
|
Term
| In contrast to murine typhus, Scrub typhus is spread by a (mite, tick, louse) and forms this type of lesion not found in Murine typhus at the bite site |
|
Definition
| Mite (chigger), eschar or scab formation |
|
|
Term
| This is the causative agent of Scrub typhus |
|
Definition
|
|
Term
| This type of serological test, also known as a heterlogous antibody test, can be used to detect the causes of typhus |
|
Definition
|
|
Term
| Depending on the adult worm's preferred habitat in the host, what three types of Onchocerciasis exist? |
|
Definition
| Cutaneous (Loa loa, O. volvulus, M. pestans, M. streptocerca), Lymphatic (W. bancrofti, B. malayi, B. timori), Body cavity (M. ozzardi, O. volvulus) |
|
|
Term
| This is the fourth leading cause of blindness in the world. |
|
Definition
|
|
Term
| True or false: humans are the only reservoir of Onchocerca |
|
Definition
| True, some animals can be infected too but not enough to be a reservoir |
|
|
Term
| This is the causative agent of Onchocerciasis (shares name with a famous sunglass company) |
|
Definition
|
|
Term
| This stage of filarial larvae is injected into the human host by the Blackfly when taking a blood meal |
|
Definition
|
|
Term
| For up to how long can the adult Onchocerca live in subcutaneous nodules in the human host? |
|
Definition
|
|
Term
| Which stage of Onchocerca is ingested when the Blackfly takes a blood meal from an infected human? |
|
Definition
| Microfilariae, then L1, L2 and L3 infects another human host |
|
|
Term
| How high can the total body load of microfilariae be in a human host? |
|
Definition
|
|
Term
| How many male and female (respectively) Onchocerca can live in one subcutaneous nodule? |
|
Definition
| 1-10 male, 20-50 females, females do not leave the nodules while males exchange constantly |
|
|
Term
| Typical clinical manifestations of Onchocerciasis include: |
|
Definition
| Skin nodules, lymphedema due to lymph node infection, and blindness |
|
|
Term
| These bacteria infect the Onchocerca and can cause blindness |
|
Definition
|
|
Term
| What is the joint tx for Onchocerca and Wohlbachia infection? |
|
Definition
| Ivermectin (macrolide derivative) and doxycycline to reduce bacterial load |
|
|
Term
| Another term for visceral leishmaniasis |
|
Definition
|
|
Term
| Though difficult to classify into species, this genus is responsible for causing leishmaniaisis |
|
Definition
|
|
Term
| Though multiple vectors and hosts are involved in Leishmania transmission, these are the primary hosts: |
|
Definition
| Dogs, gerbils, wild rodents, and humans |
|
|
Term
| True or false: following a blood meal from a female sandfly, promastigote forms of Leishmania burrow through the wound and are phagocytized by macrophages, where they develop into amastigotes |
|
Definition
|
|
Term
The five countries accounting for 90% of the cases of kala azar are:
1) India, Bangladesh, Nepal, Sudan, Brazil
2) India, Bangladesh, Nepal, Switzerland, Brazil
3) India, Burundi, Afghanistan, Colombia, Mexico
4) Argentina, Australia, Canada, Rwanda, Kansas |
|
Definition
|
|
Term
| Another name for mucocutaneous leishmaniasis |
|
Definition
|
|
Term
| True or false: secondary bacterial infections are a frequent cause of death in kala azar |
|
Definition
| True, visceral infection makes the host more susceptible to bacterial infections like TB, MAC etc. |
|
|
Term
| True or false: Increasing parasite burden correlates with mucocutaneous and asymptomatic manifestations of leishmaniasis |
|
Definition
| False, disseminated cutaneous and kala azar |
|
|
Term
| True or false: HAART for HIV + patients with leishmaniasis can be an effective tx for parasite burden as well |
|
Definition
|
|
Term
| Widespread resistance to this agent has made it necessary to tx leishmaniasis with other agents, some quite toxic like amphotericin B (ampho-terrible) |
|
Definition
| Pentavalent antimony compounds |
|
|
Term
| The three causative agents of filariasis |
|
Definition
| Wucheria bancrofti, Brugia malayi, Brugia timori |
|
|
Term
| What two types of periodicity are displayed by the microfilariae that cause filariasis? |
|
Definition
| nocturnal, and subperiodic nocturnal, where peak levels of microfilariae can occur during the day half the time or more |
|
|
Term
| True or false: clinical manifestations of lymphatic filariasis can be asymptomatic with or without microfilaremia, or can present with fever, lympangitis and lymphadenitis, and male genitalia lympatic inflammation |
|
Definition
|
|
Term
| True or false: microfilariae can be detected with a rapid antigen assay |
|
Definition
| True, can also be visualized in tissue |
|
|
Term
| The two tx for lymphatic filariasis are: |
|
Definition
| Ivermectin, an effective anti-helminthic agent and doxycycline |
|
|
Term
Contrasted with onchocerciasis, which is spread by a fly, lymphatic filariasis is spread by:
a) ticks
b) lice
c) mosquitoes
d) spiders |
|
Definition
|
|
Term
| Causative agents of trypanosomiasis are: |
|
Definition
| Trypanosoma brucei rhodiesiense (eastern) and Trypanosoma brucei gambiense (western) |
|
|
Term
| True or false: trypanosomiasis occurs mostly between the Gambia and Limpopo River in Southeast and equatorial Africa |
|
Definition
|
|
Term
| The reservoirs of both forms of T. brucei include: |
|
Definition
| Humans, wild game, domestic animals for Tbg |
|
|
Term
| This is the vector of trypanosomiasis |
|
Definition
| the Tsetse fly, or Glossina morsitans |
|
|
Term
| These protozoan forms infect the body fluids in trypanosomiasis |
|
Definition
| Trypomastigotes, injected as metacyclic trypomastigotes |
|
|
Term
| This is the gene that trypanosomes express to evade host immune systems, causing periodic bouts of symptomatic infection |
|
Definition
| variable surface glycoprotein or VSG |
|
|
Term
| True or false: Tbg causes more parasitemia and rapid toxemia than Tbr, resulting in sicker patients |
|
Definition
| False, other way around, signs and sx include immunosuprression, glomerulonephritis, anemia, thrombocytopenia, carditis, hypergammglobulemia, rash |
|
|
Term
| True or false: Tbr has its reservoir in cattle, causes acute disease, lasts <9 months, carries a high degree of parasitemia and is found mostly in Eastern Africa |
|
Definition
| True, Tbg is more chronic, tends to congregate around watering holes |
|
|
Term
| True or false: first stage trypanosomiasis is limited to the hemolymphatic tissues, while second stage disease involves CNS invasion and death |
|
Definition
| True, first stage tx with pentamidine IV, second stage much harder to treat |
|
|
Term
| Why is it important to include a staging step in the diagnostic workup for Tb? |
|
Definition
| The tx are quite different, IM pentamidine for first stage illness and eflornithine for second-stage illness |
|
|
Term
| Causative agent of babesiosis |
|
Definition
| Babesia microti & Babesia divergens, hemoprotozoans so can be confused with Plasmodium, found in the Northeast and Midwestern US |
|
|
Term
| What time of year is babesiosis most likely to occur? |
|
Definition
| Summer months into September |
|
|
Term
The white footed mouse is the primary reservoir of:
a) Babesia
b) Plasmodium
c) T. cruzii
d) Rickettsiae
|
|
Definition
| a, deer population growth is synergistic with increased tick populations |
|
|
Term
|
Definition
| Ixodes scapularis, also can be transmitted via transfusions and organ transplant |
|
|
Term
| True or false: Babesia's life cycle mimics that of malaria in most ways, except for two important points |
|
Definition
| 1, it involves two hosts, the mouse and human, and 2 the human is a dead-end host, little if any human-tick transmission takes place |
|
|
Term
| Of the two, which Babesia species causes fatal disease if untreated? |
|
Definition
|
|
Term
| Which type of stain is best for visualizing Babesia? |
|
Definition
|
|
Term
| True or false: tx is not recommended in asymptomatic or minimally ill cases of babesiosis |
|
Definition
| True, if illness increases in severity then treat with clindamycin and quinine, or atovaquone and azithromycin |
|
|
Term
| These small, gram - obligate intracellular parasites infect mammals and arthropods |
|
Definition
|
|
Term
| What part of the US does RMSF typically occur? |
|
Definition
|
|
Term
90% of RMSF occur between:
a) January and May
b) August and January
c) April and September
d) Year round |
|
Definition
|
|
Term
| True or false: I. scapularis is the tick responsible for the transmission of RMSF |
|
Definition
| False, Dermacentor variabilis |
|
|
Term
| R. ricketsii infects these cells, causing vasculitis, DIC and extravasation of fluid into surrounding tissue |
|
Definition
| Vascular endothelial cells |
|
|
Term
| True or false: RMSF has a high mortality rate if untreated, and even a 4% mortality rate with tx |
|
Definition
| True, most virulent rickettsial disease, more deadly than typhus |
|
|
Term
| Dx of RMSF is based on clinical suspicion, and the following serology tests: |
|
Definition
| Weil-Felix agglutination, microimmunofluorescence or latex agglutination |
|
|
Term
| The preferred tx for RMSF is: |
|
Definition
| Doxycycline given early in disease course, RMSF is nationally notifiable |
|
|
Term
| Causative agent of Lyme disease is: |
|
Definition
|
|
Term
| What is unique about the spirochete B. burgdorferi? |
|
Definition
| It is the only human spirochetal pathogen that contains LPS |
|
|
Term
| True or false: Lyme disease is the most common tick-borne disease in the US |
|
Definition
| True, mostly in Northeast and great lakes, more than 23,000 cases reported in '05 |
|
|
Term
| The tick vector of Lyme disease is: |
|
Definition
|
|
Term
| True or false: stage 1 of Lyme disease is caused by spirochetemia and systemic signs and symptoms, while stage 2 manifests as neuritis, carditis and possibly mengitis |
|
Definition
| True, stage III presents with polyarthritis |
|
|
Term
| True or false: Erythema migrans, the rash that appears around the bite, is diagnostic of Lyme disease in any case |
|
Definition
| False, if the erythematous patch is less than 5cm in diameter than serologic confirmation along with other symptoms are necessary, labs can isolate the spirochete or show an antibody response to the spirochete |
|
|
Term
| These are the vectors for the spread of Loa loa? |
|
Definition
| Chrysops flies that bite day and night, no temporality |
|
|
Term
| True or false: The L3 Loa loa larvae are inoculated into the human host during the Chrysops blood meal |
|
Definition
| True, they mature into adults in the subcutaneous tissue and produce microfilariae that appear in CSF, urine, sputum and the lungs |
|
|
Term
| True or false: loaiasis is often asymptomatic |
|
Definition
| True, sx include angioedema, pruritis/urticaria, hyperglobulinemia, renal dysfuction, myocardial fibrosis |
|
|
Term
| True or false: loaiasis is diagnosed via serology |
|
Definition
| False, ID'ing microfilariae in tissue samples is the most practical, there is a large amount of x-reactivity between filaria and other helminths, can't distinguish active from past infection |
|
|
Term
| Give two types of treatment for loaiasis |
|
Definition
| Abx cream on wounds to prevent secondary infxn, ivermectin kills microfilariae |
|
|
Term
| Though related to the Rickettsia bacteria, Anaplasmatacae include these pathogens: |
|
Definition
| Anaplasma and Ehrlichia, causes of anaplasmosis and ehrlichiosis (monocytic and granulocytic) |
|
|
Term
| Formerly known as human granulocytic ehrliciosis, it is now known as this disease |
|
Definition
|
|
Term
| True or false: the hosts for Ehrlichia include dogs, humans, horses, sheep, cattle and deer |
|
Definition
| True, all found worldwide, and in the US |
|
|
Term
| These two species of Ehrlichia infect human monocytes |
|
Definition
| E. canis & E. chaffeensis |
|
|
Term
| True or false: The incidence of ehrlichiosis has increased markedly in the past 10 years |
|
Definition
| True, 2006 was the highest number of cases since 1987 |
|
|
Term
| What region of the US has the most diverse and densest tick population? |
|
Definition
|
|
Term
| What is the incubation period of ehrlichiosis and anaplasmosis? |
|
Definition
|
|
Term
| True or false: dx of ehrlichiosis/anaplasmosis is labaratory based PCR or serology |
|
Definition
|
|
