TICK BORNE ILLNESS Flashcards
Organism Type:
Gram-negative, intracellular, coccobacillus bacterium
Scientific name:
R. rickettsia
Subtypes:
None
Common Name(s):
‘Spotted Fever,’ ‘black measles’
Prevalence:
Europe (central and eastern) Asia (western Russia,
Mongolia, northeastern China, and into Japan). Northeastern and
north-central United States.
Predisposing Factors:
hiking, camping, high tick population, summer
& fall months, not performing tick checks, lack of PPE/covering
(7) Transmitted Via: American dog tick - east of Rockies & Pacific
Coast, Rocky Mountain wood tick - Rocky Mountain region, brown
dog tick (worldwide)
Vector
Yes
Incubation Period:
typically 2–14 days
Vaccine
No
Reportable
Yes
Lethal
typically, no. Untreated, YES!
Peak transmission occurs in
May – August, although reported
year-round.
RMSF is a rapidly progressive disease and without early
administration of____ can be fatal within days.
doxycycline
(a) Fever, HA, GI symptoms, myalgias and rash.
1) Rash typically presents 3-5 days after fever onset
2) Begins as small flat pink macules on wrists, forearms
and ankles that spreads to trunk
3) Can also involve palms of hands & soles of feet
Early illness (days 1-4)
R. rickettsii infects endothelial cells that line blood vessels, causing
vasculitis and bleeding or clotting in the brain or other vital organs.
late Disease
Severe RMSF may cause permanent complications from
(a) Neurological deficits
(b) Damage to internal organs
(c) Vascular damage requiring amputation
( Late Disease )
(3) Patients without vascular damage in the initial stages of disease
typically experience a full recovery.
(4) There is no evidence that R. rickettsii causes persistent or chronic
disease.
late Disease
A classic RMSF involves a rash that appears 2-4 days after
the onset of fever as small, flat, pink, macules on
(1) the wrists,
forearms, and ankles and spreads to include the trunk and
sometimes the palms of hands and soles of feet
(2) Rash can be highly variable and people who fail to develop a
rash, or develop an atypical rash, are at increased risk of
being misdiagnosed.
(a) The petechial rash of RMSF does not typically appear until
day ___
5-6 of illness.
1) NOTE: Petechiae are a sign of severe disease.
(b) Every attempt should be made to treat before petechiae
develop.
Differentials
(1) Measles
(2) Hepatitis
(3) Leptospirosis
(4) Meningococcemia
(5) Infectious mononucleosis
(6) Maladie
Maladies that can produce lesions on the hands & feet:
(a) Syphilis
(b) HFMD
(c) Dyshidrosis Treatment
Diagnosis
TRAINEE GUIDE B-300-0019C
FOR TRAINING USE ONLY 27
(1) Early consideration of rickettsial disease in the DDX & empiric
treatment with doxycycline is crucial to prevent severe illness and
death.
(2) RMSF is difficult to DX due to non-specific signs & symptoms in
early illness.
(3) Crucial History findings to R/I or R/O RMSF:
(a) Recent tick bite. NOTE: Tick bites are often painless, and
many patients do not remember being bitten.
(b) While no recollection of a tick-bite lessens can potentially
lessen the suspicion for RMSF, it does not rule it out.
(c) Exposure to areas where ticks are common (wooded or
brushy areas with high grasses and leaf litter).
(d) Domestic & International travel history to areas where RMSF
is endemic.
(4) Maintain clinical suspicion of RMSF in cases of non-specific febrile
illness & sepsis of unknown origin, particularly during spring/summer
months when ticks are most active.
(5) Laboratory confirmation is helpful for disease surveillance and but
should not be relied upon to make a treatment decision.
Treatment
Doxycycline = treatment of choice for all tickborne rickettsial
diseases.
After Doxycycline TX, fever generally subsides within ___
hours,
24–48
where to expect ticks
b) Where: wooded and brushy areas with high grass and leaf
litter
(c) When: Spring/summer/fall
Treat gear & clothing with products containing
0.5%
permethrin.
Use EPA registered insect repellents
DEET or picaridin both
commonly available
Wear long pants, long sleeves, and long socks
(light-colored
clothing also helps to identify ticks)
Perform tick checks at ____ intervals when training or
operating in RMSF endemic areas. Never let your personnel
go > ___ without a check.
12-hour
24hrs
Disposition
MedEvac patient to higher echelon of care.
IDC should initiate treatment with ___while patient is still on
board.
doxycycline
