Tick-Borne, Vector-Borne & Zoonotic Illnesses
Comprehensive emergency protocol for acute vector-borne, tick-borne, and zoonotic emergencies. Covers Lyme disease stages and carditis AV blocks, Rocky Mountain Spotted Fever (RMSF) centripetal rash and non-negotiable doxycycline in all ages, Babesiosis Maltese-cross smear analysis, severe malaria artesunate resuscitation, and CDC rabies post-exposure prophylaxis protocols.
Resuscitation Quick Ribbon (First 2 Minutes)
Bottom-Line Clinical Pearl
In suspected Rocky Mountain Spotted Fever (RMSF), Doxycycline is the absolute first-line drug of choice for ALL patients, including pediatric patients of any age and pregnant women. Delaying doxycycline while awaiting serologies significantly increases fatal vasculitis and mortality.
| Disease | Vector & Organism | Incubation & Hallmark Rash | Severe Complications & First-Line Regimen |
|---|---|---|---|
| Lyme Disease | Ixodes scapularis (Deer tick); Borrelia burgdorferi | 7-14 days; Erythema Migrans (expanding bullseye lesion > 5 cm with central clearing) | Early disseminated: Lyme carditis (AV nodal block), Bilateral facial nerve (Bell's) palsy. Late: migratory oligoarthritis. Regimen: Doxycycline 100 mg PO BID x 14-21d (Ceftriaxone IV for carditis/CNS). |
| Rocky Mountain Spotted Fever (RMSF) | Dermacentor variabilis (Dog tick) / Dermacentor andersoni; Rickettsia rickettsii | 2-14 days; Blanching maculopapular rash starting on WRISTS AND ANKLES on day 3-5, spreading CENTRIPETALLY to palms, soles, arms, legs, and trunk; becomes petechial | Fulminant microvascular endothelial damage, non-cardiogenic pulmonary edema, DIC, gangrene, multi-organ failure. Regimen: DOXYCYCLINE 100 mg PO/IV BID x 7-10d FOR ALL AGES (including young children). |
| Babesiosis | Ixodes scapularis; Babesia microti (protozoan) | 1-4 weeks; NO RASH; viral-like fever, chills, drenching sweats | Severe hemolytic anemia, jaundice, hemoglobinuria, thrombocytopenia, splenic rupture. Smear: Intraerythrocytic tetrads ('Maltese cross'). Regimen: Atovaquone + Azithromycin (exchange transfusion if parasitemia > 10%). |
| Anaplasmosis / Ehrlichiosis | Ixodes (Anaplasma) / Amblyomma (Ehrlichia); intracellular bacteria | 1-2 weeks; Rash rare; leukopenia, thrombocytopenia, elevated transaminases | Peripheral smear: Intracytoplasmic morulae in granulocytes (Anaplasma) or monocytes (Ehrlichia). Regimen: Doxycycline 100 mg PO/IV BID x 10-14d. |
| Immune Status | Human Rabies Immune Globulin (HRIG) | Rabies Vaccine Regimen (HDCV or PCECV) |
|---|---|---|
| Previously Unvaccinated | HRIG 20 IU/kg body weight administered ONCE on Day 0. Infiltrate as much of the full calculated volume as anatomically feasible DIRECTLY INTO AND AROUND the wound(s); inject any remaining volume IM at an anatomic site distant from the vaccine (e.g. quadriceps or gluteus). | 4 Doses: 1.0 mL IM administered in the deltoid on Days 0, 3, 7, and 14 (add a 5th dose on Day 28 if immunocompromised). NEVER inject vaccine in the gluteal muscle (reduced absorption and efficacy). |
| Previously Vaccinated (Documented series) | DO NOT ADMINISTER HRIG (causes blunting of secondary memory immune response) | 2 Doses: 1.0 mL IM administered in the deltoid on Day 0 and Day 3 only. |
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