Lyme & Other TBD Treatment in Pregnancy: New guidance

In a recently published review article,* authors provide a comprehensive summary of treatment options for pregnant patients with less common bacterial, fungal, and viral infections, including several tick-borne diseases (Lyme disease, ehrlichiosis, human granulocytic anaplasmosis, human monocytic ehrlichiosis, babesiosis, and Rocky Mountain spotted fever). This review provides guidance to clinicians based on the most recently published evidence-based research and expert recommendations.

The review  included a search of MEDLINE (inception to March 2021); clinical practice guidelines (both national and international); the CDC website; and additional references from bibliographies of noteworthy articles. The review also provides a list of medications on the WHO Essential Medications List that are used to treat the above infections (*Alyssa P. Gould et al., Drugs in Context-peer reviewed).

NOTE:  The information presented is for informational purposes only. The LDA does not give medical or legal advice. Any information on the site should not be used to take the place of advice from your personal physician or from any other professional. Any health care or legal information on the website is attributed to the professional(s) who wrote the information and is not necessarily endorsed by the Lyme Disease Association. Links to other sites are provided for ease of research, and information on those sites is the opinion of those who publish the sites and is not necessarily that of the LDA. The LDA does not endorse professionals, products or services.


A summary of key treatment recommendations from the review article for several tick-borne diseases during pregnancy are as follows:

Lyme disease:
  • Treatment of gestational Lyme disease is essential to reduce adverse outcomes in pregnancy. The data shows adverse outcomes in treated pregnancy is (11–16%) compared to untreated disease (50–60%).
  • Doxycycline should not routinely be used in pregnancy for Lyme disease in order to avoid adverse side effects including transient suppression of bone growth and staining of developing teeth, especially with proven alternatives.
  • Amoxicillin is the preferred treatment in the absence of neurological manifestations or atrioventricular heart block. 
  • Ceftriaxone is typically reserved for patients with severe neurological or cardiac manifestations. 
  • One study noted a non-significant increase in adverse pregnancy outcomes, such as pregnancy loss, among orally treated (31.6%) compared to parenterally treated (12.1%) pregnant patients.
  • Alternative oral therapy is cefuroxime axetil and parenteral therapies include penicillin G or cefotaxime.
  • Late Lyme disease (often manifesting as Lyme arthritis) may be managed with oral or parenteral β-lactams. 
Ehrlichiosis & Anaplasmosis:
  • If infections with anaplasmosis or ehrlichiosis is suspected, treatment should be initiated due to the likelihood of complications and potential for vertical transmission of disease. 
  • Rifampin has shown in vitro activity against ehrlichia and has been used successfully in limited case reports of pregnant women with anaplasmosis.
  • Doxycycline has been used successfully to treat ehrlichiosis.
  • Due to a lack of data, these pregnant patients should be closely monitored for resolution of disease.
  • The addition of amoxicillin or cefuroxime is suggested if coinfection with Lyme disease is suspected, as rifampin does not have activity against B. burgdorferi.
  • Patients with suspected babesiosis should be treated due to potential complications, including possible vertical transmission to the fetus.
  • Combination therapy is preferred with clindamycin plus quinine. 
  • Longer treatment courses or retreatment may be needed in cases with symptoms and/or parasitaemia persisting >3 months. Resolution of parasitaemia should be used to determine treatment course.
Rocky Mountain spotted fever (RMSF):
  • RMSF cases are associated with poor outcomes for the fetus, regardless of the treatment.
  • Prevention is crucial for pregnant patients, and treatment should be provided within 3–5 days of exposure.
  • Doxycycline is the preferred therapy. Treatment course is typically 5–7 days or 3 days after fever resolution.
  • Chloramphenicol is a proposed alternative treatment; but there are concerns for significant adverse effects, including myelosuppression, aplastic anaemia, and grey baby syndrome, specifically at or near birth, and it is associated with higher mortality in RMSF. (chloramphenicol is not available orally in the US).

Read the full review article here

Read other LDA articles regarding treatment here

Ehrlichiosis Infection Following Organ Donation

In a recent article, investigators describe multiple cases of organ transplant derived Ehrlichiosis infections in donor recipients. Two cases of ehrlichiosis were reported to the Organ Procurement and Transplantation Network (OPTN) and the Centers for Disease Control and Prevention (CDC) for investigation in 2020. These two kidney recipients from a common donor developed fatal ehrlichiosis-induced hemophagocytic lymphocytic histiocytosis (HLH). Additionally, two kidney recipients and a liver recipient from another common donor developed ehrlichiosis, and  were all treated successfully. Investigators suggest that donor-derived ehrlichiosis should be considered by clinicians when evaluating recipients with fever early after transplantation after more common causes are ruled out, and cases that are suspected for Ehrlichiosis should be reported to the organ procurement organization (OPO) and the OPTN for further investigation.

Access to full article here.

Read more LDA articles on Ehrlichiosis here.

Blocking Tick-Borne Infection with Nanobodies

Fig. 8. D7, but not D3, abrogates E. chaffeensis-induced increase in MnSOD and reduction in ROS and inhibits infection. (A) HEK293 cells were transfected with HA-tagged Nbs and infected with E. chaffeensis (Ech) at 1 dpt. Native E. chaffeensis Etf-1, E. chaffeensis outer membrane proteins P28/OMP-1F, Nbs, MnSOD, and human actin were detected at 2 dpi by Western blotting using their respective antibodies. (B, D, and E) Quantification of relative densities of MnSOD (B), P28 (D), and Etf-1 (E) normalized against actin. (C) ROS production at 2 dpi was analyzed by the fluorescent indicator H2DCFDA. Null, buffer control without H2DCFDA. (B−E) Data are presented as the mean ± SD from three independent experiments with triplicates per sample. *P < 0.05, by one-way ANOVA.

Ohio State University researchers have just published an article on their creation of nanobodies which target the protein that causes E. chaffeensis bacteria to be extremely infectious. Nanobodies are small molecules that can be designed to mimic the function  and structure of antibodies and may be the solution to inhibit tick-borne bacterial infections that remain inaccessible by most current antibiotics due to the fact that they reside and replicate inside human immune cells. 

Researchers conducted a number of experiments in both mice and cell cultures which identified one specific nanobody that could suppress E. chaffeensis infection by blocking three ways the protein enables the bacteria to commandeer immune cells. It is thought that these nanobodies can be developed as a new or complementary therapy for human monocytic ehrlichiosis as well as other tick-borne diseases that are caused by intracellular infections, infections that can be fatal if left untreated or undertreated. 

Read Science Daily article here.

Read full text Ohio State research article here.

Read more LDA posts on Ehrlichiosis here.


Scientists used to separate ehrlichiosis into two entities caused by the bacterium Ehrlichia: Human Monocytic Ehrlichiosis (HME) and Human Granulocytic Ehrlichiosis (HGE).  After further study, they determined that HGE is actually caused by a bacterium, Anaplasma phagacytophilum.  HME is caused by a bacterium, Ehrlichia chaffeensis.

Symptoms of ehrlichiosis/anaplasmosis include: fever, malaise, headaches, chills, severe muscle aches, vomiting, anemia, lung infection, decreased white blood cells and platelets, elevated liver enzymes, seizures, encephalopathy, meningitis, confusion, ataxia and cranial nerve palsy. Co-infection with Lyme can cause more severe symptoms. Death can result.

Treatment is with doxycycline. 

Ticks that transmit anaplasmosis include Ixodes scapularis (deer tick or black legged tick) and Ixodes pacificus (western black legged tick).

Ticks that transmit ehrlichiosis (HME) include Amblyomma americanum (lone star) and Dermacentor variabilis (American dog).  Ixodes scapularis (deer tick or black legged tick) and Ixodes pacificus (western black legged tick) ticks have been shown to carry the ehrlichiosis bacterium, but to date, transmission is still in question.

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