Tick Borne Illness

Question 1

Common Name(s): ‘Spotted Fever,’ ‘black measles’

Answer 1

Rocky Mountain Spotted Fever (RMSF)

Question 2

Where is RMSF prevalent

Answer 2

• Endemic in Central & South America
• Occur throughout the United States, but are most commonly reported from North Carolina, Tennessee, Missouri, Arkansas, and Oklahoma.

Question 3

Predisposing factors for RMSF

Answer 3

• Hiking, camping
• High tick population
• Spring, summer & fall months
• Not performing tick checks, lack of PPE/covering.

Question 4

How is RMSF transmitted

Answer 4

• American dog tick - East of Rockies & Pacific Coast
• Rocky Mountain wood tick - Rocky Mountain region
• Brown dog tick -Worldwide

Question 5

Incubation for RMSF

Answer 5

Typically 2–14 days

Question 6

Can you become unalive from RMSF

Answer 6

Typically, no. Untreated, YES!!

Question 7

When is peak transmission for RMSF

Answer 7

occurs in May – August, although reported year-round.

Question 8

S/s:
- Days 1-4
- Fever, HA, GI symptoms, myalgias, edema around eyes & back of hands, and rash.

Answer 8

Rocky Mountain Spotted Fever- Early Illness

Question 9

S/s:
- Day 5 or later
- Vasculitis and bleeding or clotting in the brain or other vital organs
- Neurological deficits
- Damage to internal organs (respiratory compromise, renal failure)
- Vascular damage requiring amputation

Answer 9

RMSF – Late illness

Question 10

Patients without vascular damage in the initial stages of disease experience what kind of recovery?

Answer 10

Full recovery

Question 11

Can R. rickettsii cause persistent or chronic
disease?

Answer 11

No

Question 12

What percentage of patients with RMSF have some type of rash during the course of their illness?

Answer 12

• 90% however, <50% will have it in within 3 days of illness when most seek care

Question 13

Describe the early rash of RMSF

Answer 13

• Appears 2-4 days after the onset of fever as small, flat, pink, macules on the:
• Wrists
• Forearms
• Ankles
• Spreads tot he trunk and to palms and soles of feet

Question 14

HPI/ S/S:
- Recent tick bite
- Exposure to areas where ticks are common
- Domestic & International travel history where ticks are common
- Non-specific febrile illness & sepsis of unknown origin, particularly during spring/summer
months when ticks are most active.

Answer 14

Rocky Mountain Spotted Fever

Question 15

Treatment of RMSF

Answer 15

Doxycycline = treatment of choice for all tickborne rickettsial diseases.100mg PO BID for 5 – 7 days; or for 3 days AFTER fever subsides.

Question 16

Labs for RMSF

Answer 16

CBC & Chem
Molecular – PCR
Serology – Immunofluorescence Antibody Assay (IFA)

Question 17

Prevention of RMSF

Answer 17

• Know where to expect ticks
• What: Medical Intel resources (DoD or public)
• Where: Wooded and brushy areas with high grass and leaf litter
• When: Spring/summer/fall

Question 18

Gear Prep for RMSF

Answer 18

• Treat gear & clothing with products containing 0.5% permethrin.
• UseEPA 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)

Question 19

How often should tick checks be done for RMSF

Answer 19

• Perform tick checks at 12-hour intervals when training or operating in RMSF endemic areas.
• Never let your personnel go > 24hrs without a check.

Question 20

Disposition for RMSF

Answer 20

• MedEvac patient to higher echelon of care.
• IDC should initiate treatment with doxycycline while patient is still on board.
• When caught & treated early (symptomatic patients), RMSF may never progress in severity, however, patient still requires MedEvac for monitoring and laboratory studies.