Ehrlichiosis
(Ehrlichia chaffeensis & Ehrlichia ewingii)
Species
Rickettsial
Rickettsial
bacterial
Transmission time
18 - 24
18 - 24
Hours
Details
Symptoms
- Symptoms may begin 1-2 weeks after exposure.
- Symptoms include:
- Chills, sweats, headache, fatigue, nausea, diarrhea, vomiting, fever
- Joint and muscle pain
- Disorientation, rash, and eye infection
- Trouble breathing and kidney dysfunction may occur in immunocompromised individuals.
- Headache and fatigue may continue for a few weeks after treatment.
Diagnosis and Treatment
- Polymerase Chain Reaction (PCR) of the blood within the first week of infection can detect Ehrlichia DNA.
- Peripheral blood smears may show Ehrlichia in white blood cells confirming diagnosis.
- Indirect Immunofluorescence Assays (IFA) is a two-part test used to detect antibodies.
- The first sample is collected within 7 days of infection and will be compared to the second sample collected 2-4 weeks after infection.
- If the second sample shows the number of antibodies present has increased since the first sample was tested, the results are positive for Ehrlichia .
- False positives are common for the first part of the test.
- Low platelet and white blood cell counts or elevated liver enzymes may suggest Ehrlichiosis infection.
CDC Treatment Recommendation
- Adult: Doxycycline 100mg-2x daily for 7-14 days
- Children: 2.2mg/kg-2x daily for 7-14 days
Disease Pathogenesis
- Ehrlichia chaffeensis will cause Human Monocytic Ehrlichiosis by invading white blood cells known as monocytes. The immune system will destroy infected cells in response to the infection causing disease symptoms.
- Ehrlichia ewingii will cause Human Granulocytic Ehrlichiosis by invading white blood cells known as granulocytes. The immune system will destroy infected cells in response to the infection causing disease symptoms.