Tick-borne Illnesses Lecture Flashcards Preview

Infectious Disease > Tick-borne Illnesses Lecture > Flashcards

Flashcards in Tick-borne Illnesses Lecture Deck (65)
Loading flashcards...
1

Borrelia burdorferi ss

Lyme disease

2

Babesia microti

Human babesiosis

3

Anaplasma phagocytophila

Human granulocytic anaplasmosis

4

-Multisystem inflammatory disease
-Causes by spirochetes: Borrelia burgdorferi – identified in 1981
-Spread by Ixodes ticks

Lyme disease

5

Transmission: Bite of an infected nymph in the spring
Preferred host: White-tailed deer

Lyme disease

6

Egg
Six-legged larvae
Eight-legged nymph
Adult

Life cycle of hard ticks

7

Adults peak in spring and fall – preferred host is white-tailed deer. Mating occurs.
Nymphs peak May-July – aggressive - frequently bite humans
Larvae peak August-September (from eggs on the ground)

Life cycle of Ixodes scapularis

8

To transmit lyme dz bacterium, ticks must feed for at least.....

24 hours

9

_____ secrete an anesthesia and anticoagulant when biting

Ticks

10

Blacklegged (or deer) ticks (Ixodes scapularis can transmit several tick-borne diseases including:

anaplasmosis
babesiosis
Lyme disease

11

Which type of ticks most commonly bite humans, adult or nymphal?

Nymphal

12

Agent – Anaplasma phagocytophilum
Originally confused with Ehrlichiosis
Tick – Ixodes scapularis
Animal reservoir (deer and white footed mouse)

Human Anaplasmosis (aka Human Granulocytic Anaplasmosis)

13

-Bacterial infection: Caused by the rickettsial agent Anaplasma phagocytophilum

-Infects white blood cells: Granulocytes

-Unknown transmission time from tick: Suspected to be between 24 and 48 hours

Human Anaplasmosis

14

Bacterial diseases
Ehrlichia chaffeensis
Ehrlichia ewingii
Anaplasma phagocytophilum

Ehrlichiosis

15

Cause is unknown
Rash appearance similar to Lyme disease
Has not been linked to arthritic, neurologic, or chronic symptoms
Transmitted by lone star tick
Most cases found in southeastern US

Southern Tick Associated Rash Illness (STARI)

16

Incubation period – 1 to 2 weeks
Fever, chills, severe headache – common
Malaise, Myalgia, Arthralgia – also common
Cough, GI upset, stiff neck – less common

"summer-flu"

Anaplasmosis

17

Mild anemia
Thrombocytopenia
Leukopenia with a left shift
Mild elevation of LFT’s

Anaplasmosis

18

Anaplasmosis diagnosis is made via...

PCR assay for DNA

19

Four-fold rise in IgG antibody by IFA
Immunochemistry staining of organism
Isolation in cell culture

Diagnosis of Anaplasmosis

20

Anaplasmosis tx for adults...

Doxycycline

(if Doxy resistant, consider Rifampin)

21

Anaplasmosis tx for kids..

start with Doxy, may follow up with Beta-lactam

22

Parasitic infection:
Caused by protozoa of the Babesia genus (Babesia microti and others)

Babesiosis

23

Infects RBCs
Unknown transmission time from tick

Babesiosis

24

Tick-borne illness
Protozoa of family Babesiidae
Animals: rodents and small mammals
**enters RBCs and causes hemolysis
Vector= Ixodid tick

Babesiosis

25

Incubation period.. 1-3 weeks following tick bite. 6-9 weeks following blood transfusion

Babesiosis

26

Fever, chills, sweats
Myalgias, arthralgia, fever
N/V

Exam shows: splenomegaly, hepatomegaly, jaundice

Babesiosis

27

High-level parasitemia (> 10 percent)
Significant hemolysis ( plus DIC)
Renal, hepatic, pulmonary compromise

Risk factors:
Age over 50 years
Asplenia,Malignancy,HIV,Immunosuppressives

Severe Babesiosis

28

Asymptomatic Disease—Common
1 May not need treatment
2 Can be monitored – clear 4-6 weeks
3 If no underlying disease- watch

Babesiosis

29

Laboratory: Anemia-thrombocytopenia-increased conjugated bilirubin

Confirmation: Blood smear- Intra-erythrocytic parasites

PCR **

Serology: Indirect immunofluorescent antibody test

Dx of Babesiosis

30

Clindamycin/Quinine or Atovaquone/Azithromycin

First line tx for Babesiosis