ticks and bugs and stuffs

Question 1

pathogen, vector, and host of lyme disease?

Answer 1

pathogen: borrelia burgdorferi (gram negative spirochete)
vector: ixodes scapularis (blacklegged deer ticks)
host: white tailed deer

Question 2

during which life cycle phase do ticks typically bite and infect humans with lyme?

Answer 2

nymphal stage!

Question 3

how long must a ticks bloodmeal be in order to infect a human? what must occur?

Answer 3

24-48 hours to get the bacterium from the gut to the mouth, there must be OSPa to OSPc conversion because A is not infectious but C is!

Question 4

what does a tick secrete when it bites us?

Answer 4

an anesthetic and anticoagulant

hinders pain and clotting so we can’t detect it when it happens!

Question 5

what is the first stage of a lyme disease infection?

Answer 5

erythema migrans (80 percent); bullseye rash that shows up 7-10 days post bite and is sometimes associated with viral-like syndrome (headaches, fever, malaise)

Question 6

what is the second stage of a lyme infection?

Answer 6

early disseminated (1-2 weeks)

• arthralgias
• multiple erythema migrans
• CN 7 palsy, radiculoneuritis, neuropathy
• AV BLOCK!

Question 7

what does late disease (over 6 months) of lymes disease consist of?

Answer 7

persistent arthritis (usually knee), neurological issues (peripheral axonal neuropathy, mild encephalopathy, encephalomyelitis)

Question 8

how do we diagnose lyme disease?

Answer 8

often clinically
ELISA followed by western blot if ELISA positive

PCR can be done in research labs

Question 9

treatment of lyme disease?

Answer 9

doxycycline in adults; amoxicillin DOC in children 9 years and younger

Question 10

when would we consider treating lyme with IV ceftriaxone?

Answer 10

complete heart block, CNS diseases

Question 11

what is post-lyme syndrome?

Answer 11

prior LD with stabilization post RX; persistence of fatigue, MSK pain, cognitive complaints past 6 months

Question 12

what are the four conditions in which prophylaxis with doxycycline is indicated for lyme?

Answer 12

1) tick has been identified as engorged deer tick attached over 36 hours
2) exposure occurred in an area where there is a high rate of infected ticks
3) prophylaxis can be started within 72 hours
4) doxy treatment is not contraindicated

**even if prophylaxis used, monitor symptoms for 30 days

Question 13

do we continue to treat people with post-lyme syndrome with ABX?

Answer 13

NO!

Question 14

pathogen and vector for rocky mountain spotted fever?

Answer 14

pathogen: rickettsia rickettsi (spirochete bacteria)
vector: dermacentor (hard or dog) ticks

Question 15

which of our tick disease is potentially fatal but easily curable? how do we treat it?

Answer 15

rocky mountain spotted fever, treat with doxycycline (even in children)

Question 16

what type of acquisition accounts for the majority of rocky mountain spotted fever cases?

Answer 16

peridomestic acquisition

Question 17

who is most likely to acquire RMSF?

Answer 17

MALE CHILDREN

Question 18

early symptoms vs. late symptoms of RMSF?

Answer 18

early: high fever, headache, myalgia, GI symptoms
late: RASH, photophobia, confusion, ataxia, seizures, JAUNDICE, thrombocytopenia, hyponatremia

Question 19

how does the rash of RMSF present?

Answer 19

red maculopapular rash FIRST on wrists/ankles/forearms that spreads centrally to the trunk

petechiae after day 6

face usually spared!

Question 20

long term sequelae of RMSF?

Answer 20

CNS deficits, amputations

Question 21

why is diagnosis of RMSF difficult?

Answer 21

85% of patients lack diagnostic titers in first week of illness

need to test acute and convalescent samples (2-4 weeks apart) via indirect immunofluorescence; a four-fold rise in titers is confirmatory

Question 22

pathogen, vector, and reservoir for anaplasmosis?

Answer 22

pathogen: BACTERIAL infection (caused by rickettsial agent anaplasma phagocytophilum)
vector: ixodes scapularis (black legged tick)
reservoir: HGA: deer & white footed mouse

Question 23

what is the pathogenesis of anaplasmosis?

Answer 23

infects WBC and granulocytes over 24-48 hours

you will see granulocytes on peripheral blood smear

Question 24

where is ehrlichiosis most common? what tick is responsible for infecting humans?

Answer 24

south!

lonestar tick

Question 25

what is STARI? how does it present?

Answer 25

southern tick associated rash illness cause is unknown; transmitted by lonestar tick get similar rash as lyme but NO arthritic, neurologic, or chronic symptoms

Question 26

what disease is considered our "summer flu"? how does it present?

Answer 26

anaplasmosis fever, chills, severe headache, malaise, myalgia, arthralgia some cough, GI upset, stiff neck

Question 27

what laboratory findings are associated with anaplasmosis?

Answer 27

mild anemia thrombocytopenia leukopenia with a left shift mild elevation of LFT

Question 28

how do we diagnose anaplasmosis?

Answer 28

PCR assay for DNA four-fold rise in IgG antibody by IFA immunochemistry staining of organism

Question 29

treatment of anaplasmosis?

Answer 29

doxycycline

Question 30

which of our tick infections is a parasitic infection?

Answer 30

babesiosis! caused by protozoa of the babesia genus

Question 31

pathogen, vector, and reservoir for babesiosis?

Answer 31

pathogen: babesia microti vector: ixodid tick reservoir: ANIMALS! rodents and small animals

Question 32

where does babesiosis primarily infect?

Answer 32

the red blood cells! causes hemolysis considered the "american malaria"

Question 33

where in the US is babesiosis most common?

Answer 33

northeast!

Question 34

incubation period for babesiosis?

Answer 34

following tick bite: 1-3 weeks following blood transfusion: 6-9 weeks

Question 35

symptoms of babesiosis? what will PE look like?

Answer 35

fever, chills, myalgia, arthralgia, fatigue, NV PE: splenomegaly, hepatomegaly, JAUNDICE

Question 36

what are some risk factors of developing severe disease with babesiosis?

Answer 36

``` over 50 asplenia malignancy HIV immunosuppressives ```

Question 37

is asymptomatic disease common in babesiosis? why is this nervewracking?

Answer 37

YES. this is how it is transmitted via infusion!

Question 38

how does severe babesiosis present?

Answer 38

high-level parasitemia (over 10 percent) significant hemolysis (plus DIC) renal, hepatic, pulmonary compromise

Question 39

how will labs look for someone with babesiosis?

Answer 39

anemia, thrombocytopenia, increased conjugated bilirubin

Question 40

how do we diagnose babesiosis?

Answer 40

blood smear (intra-erythrocytic parasites) PCR serology for antibody testing

Question 41

first line treatment for babesiosis?

Answer 41

clindamycin/quinine OR atovaquone/azithromycin

Question 42

which tickborne disease is uncommon but has been found in every state besides hawaii?

Answer 42

tularemia 125 cases/year

Question 43

what type of tickborne disease is tularemia?

Answer 43

bacterial disease (francisella tularensis) gram-negative, non-motile, non-sporulating coccibacillus

Question 44

how is tularemia transmitted?

Answer 44

via the american dog tick, lone star tick, and rocky mountain wood tick, deer fly bites, inhalation, ingestion, or skin contact with infected animals

Question 45

what species does tularemia infect? who are the vectors?

Answer 45

small mammals (squirrels, rabbits, muskrats, etc.) arthropod vectors (ticks, biting flies, mosquitoes)

Question 46

which of our tickborne diseases kills less than 50 people a year worldwide?

Answer 46

tularemia

Question 47

why is tularemia so concerning in terms of transmission?

Answer 47

it is HIGHLY infectious (inhalation of 10 bacteria can cause disease)

Question 48

can tularemia be spread person to person?

Answer 48

NO! just by arthropod intermediates or animal bites

Question 49

what are the types of disease forms that tularemia can cause?

Answer 49

ulceroglandular (less than 5 percent mortality) oculoglandular typhoidal syndrome (30-60 percent mortality) oropharyngeal gastrointestinal pneumonia

Question 50

what is the gold standard for diagnosing tularemia?

Answer 50

PCR! know there is a high risk to lab personnel with culture

Question 51

treatment of tularemia?

Answer 51

streptomycin, gentamycin ciprofloxacin mortality=0 with treatment

Question 52

what is the name for the group of acute infections caused by the athropod born spirochetes of the genus borrelia?

Answer 52

relapsing fevers

Question 53

what are relapsing fevers characterized by?

Answer 53

infection by borrelia genus recurrent cycles of febrile episodes, separated by asymptomatic intervals of apparent recovery

Question 54

borrelia recurrentis causes what type of relapsing fever?

Answer 54

louse-borne relapsing fever! case fatality is 10% spread when uninfected human crushes infected louse and it enters abraded skin invades bloodstream

Question 55

bartonella quintana causes what type of relapsing fever?

Answer 55

trench fever! less serious (flu-like symptoms), rarely fatal characteristic five-day fever

Question 56

rickettsia prowazekii is responsible for causing what type of relapsing fever?

Answer 56

epidemic typhus! significant contributor to worldwide mortality prior to ABX

Question 57

which of our relapsing fevers is considered a category B bioterrorism agent?

Answer 57

epidemic typhus! caused by rickettsia prowazekii

Question 58

which type of lice is the only lice that can transmit disease?

Answer 58

body lice!! pediculosis humanus

Question 59

what is the pathogenesis of relapsing fever?

Answer 59

1) lice is crushed 2) incubation period 5-10 days 3) patient produces neutralizing antibodies (clear circulating strain in 3-5 days) 4) new antigenic variants appear (3-5 relapses may occur)

Question 60

treatment of relapsing fever?

Answer 60

penicillins | tetracyclines