BACKGROUND: Lyme disease (LD), the most common vector-borne disease in the United States, typically presents with a localised erythema migrans rash (EM). Left untreated, infection can disseminate to cause severe heart, joint or nervous system manifestations. Summaries of LD surveillance data have been published previously but did not include the frequency, demographic or clinical characteristics of LD cases during pregnancy. METHODS: We summarised confirmed and probable LD cases by pregnancy status as reported to the U.S. Centers for Disease Control and Prevention during 1992-2019. We defined an LD case during pregnancy as one with (1) female sex, (2) age 14-49 years and (3) positive pregnancy indication. We evaluated the frequency, seasonality, age distribution, race and ethnicity, geographic distribution and clinical manifestations of LD cases during pregnancy and cases among non-pregnant females. We compared proportions using chi-squared tests. RESULTS: Among 698,876 reported LD cases, 112,002 (16%) were confirmed or probable cases among females aged 14-49 years; 32,301 (29%) were specifically reported as non-pregnant and 643 (0.6%) (568 confirmed and 75 probable cases) reported as pregnant. Illness onset peaked in June among LD cases during pregnancy, but in July for cases among non-pregnant females. A higher proportion of confirmed LD cases during pregnancy had only EM rash than did cases among non-pregnant females (66% vs. 60%, p = 0.019). CONCLUSIONS: LD cases during pregnancy are rare. Compared to non-pregnant females, cases among pregnant females more commonly involve early clinical manifestations. These patterns could suggest earlier detection or more complete reporting of LD cases during pregnancy than their non-pregnant counterparts. Earlier detection could be due to frequent contact with healthcare or increased self-advocacy during pregnancy. Prompt antimicrobial treatment is critical for preventing severe disease and reducing risk of adverse pregnancy or birth outcomes.

BACKGROUND: Francisella tularensis, the causative agent of tularemia, is endemic throughout the Northern Hemisphere and requires as few as 10 organisms to cause disease, making this potential bioterrorism agent one of the most infectious bacterial pathogens known. Aminoglycosides, tetracyclines, and, more recently, fluoroquinolones are used for treatment of tularemia; however, data on the relative effectiveness of these and other antimicrobial classes are limited. METHODS: Nine databases, including Medline, Global Health, and Embase, were systematically searched for articles containing terms related to tularemia. Articles with case-level data on tularemia diagnosis, antimicrobial treatment, and patient outcome were included. Patient demographics, clinical findings, antimicrobial administration, and outcome (eg, intubation, fatality) were abstracted using a standardized form. RESULTS: Of the 8878 publications identified and screened, 410 articles describing 870 cases from 1993 to 2023 met inclusion criteria. Cases were reported from 35 countries; more than half were from the United States, Turkey, or Spain. The most common clinical forms were ulceroglandular, oropharyngeal, glandular, and pneumonic disease. Among patients treated with aminoglycosides (n = 452 [52%]), fluoroquinolones (n = 339 [39%]), or tetracyclines (n = 419 [48%]), the fatality rate was 0.7%, 0.9%, and 1.2%, respectively. Patients with pneumonic disease who received ciprofloxacin had no fatalities and the lowest rates of thoracentesis/pleural effusion drainage and intubation compared to those who received aminoglycosides and tetracyclines. CONCLUSIONS: Aminoglycosides, fluoroquinolones, and tetracyclines are effective antimicrobials for treatment of tularemia, regardless of clinical manifestation. For pneumonic disease specifically, ciprofloxacin may have slight advantages compared to other antimicrobials.

BACKGROUND: Tularemia, a potentially fatal zoonosis caused by Francisella tularensis, has been reported from nearly all US states. Information on relative effectiveness of various antimicrobials for treatment of tularemia is limited, particularly for newer classes such as fluoroquinolones. METHODS: Data on clinical manifestations, antimicrobial treatment, and illness outcome of patients with tularemia are provided voluntarily through case report forms to the US Centers for Disease Control and Prevention by state and local health departments. We summarized available demographic and clinical information submitted during 2006-2021 and evaluated survival according to antimicrobial treatment. We grouped administered antimicrobials into those considered effective for treatment of tularemia (aminoglycosides, fluoroquinolones, and tetracyclines) and those with limited efficacy. Logistic regression models with a bias-reduced estimation method were used to evaluate associations between antimicrobial treatment and survival. RESULTS: Case report forms were available for 1163 US patients with tularemia. Francisella tularensis was cultured from a clinical specimen (eg, blood, pleural fluid) in approximately half of patients (592; 50.9%). Nearly three-quarters (853; 73.3%) of patients were treated with a high-efficacy antimicrobial. A total of 27 patients (2.3%) died. After controlling for positive culture as a proxy for illness severity, use of aminoglycosides, fluoroquinolones, and tetracyclines was independently associated with increased odds of survival. CONCLUSIONS: Most US patients with tularemia received high-efficacy antimicrobials; their use was associated with improved odds of survival regardless of antimicrobial class. Our findings provide supportive evidence that fluoroquinolones are an effective option for treatment of tularemia.