Bacillus anthracis is a gram-positive, spore-forming, aerobic bacterium. It can cause three main types of clinical anthrax: inhalational, cutaneous, and gastrointestinal (Centers for Disease Control and Prevention, 2017a). The bioterrorist anthrax attacks of 2001 involved inhalational anthrax (Inglesby, 2002). Spores are inhaled and deposited in the alveoli. They are engulfed by macrophages and germinate in mediastinal lymph nodes. The incubation period is usually less than 1 week but may be as long as 2 months. Within 1 to 5 days of symptom onset, the second stage is heralded by the abrupt onset of severe respiratory distress and high fevers. Mediastinitis and hemorrhagic thoracic lymphadenitis are common. Chest radiographs show a widened mediastinum. Case-fatality rates with inhalational anthrax are high, even with aggressive antibiotic and supportive therapy (Holty, 2006).
Anthrax afecting pregnant women and its treatment were reviewed by Meaney-Delman and coworkers (2012, 2013). They reported data on 20 pregnant and postpartum women. The overall mortality rate was 80 percent, with a 60-percent fetal or neonatal loss rate. Of note, most cases were published before the advent of antibiotics.
Regimens for postexposure anthrax prophylaxis are given for 2 months. The CDC recommend that asymptomatic pregnant and lactating women with documented exposure to B anthracis be given postexposure prophylaxis with ciproloxacin, 500 mg orally twice daily for 60 days (Hendricks, 2014; Meaney-Delman, 2013). Amoxicillin, 500 mg orally three times daily, can be substituted if the strain is proven sensitive. In the case of ciproloxacin allergy and either penicillin allergy or resistance, doxycycline, 100 mg orally twice daily, is given for 60 days. Risks from anthrax far outweigh any fetal risks from doxycycline (lvleaney-Delman, 2013).
The anthrax vaccine is an inactivated, cell-free product that requires three injections over 28 days. Vaccination is generally avoided in pregnancy because safety data are limited. Inadvertent vaccination of pregnant women with the vaccine has not been linked with a significant increase in fetal malformation or miscarriage rates (Conlin, 2015; Ryan, 2008). The anthrax vaccine is an essential adjunct to postexposure antimicrobial prophylaxis, even in pregnancy.
Other category A bioterrorism agents include Francisella tularemis-tularemia, Clostridium botulinum-botulism, Yersinia pestis-plague, and viral hemorrhagic fevers-for example, Ebola, Marburg, Lassa, and Machupo. The guidelines for these biological agents are evolving and are detailed at the CDC Bioterrorism website: emergency.cdc.gov/bioterrorism/index.asp.
Abdoli A, Dalimi A, Arbabi M, et al: Neuropsychiatric manifestations of latent toxoplasmosis on mothers and their ofspring. J Matern Fetal Neonatal Med 27(13):1368,t2014
Adams LL, Gungor S, Turan S, et al: When are amniotic luid viral PCR studies indicated in prenatal diagnosis? Prenat Diagn 32(1):88, 2012
Adams Waldorf KM, McAdams M: Inluence of infection during pregnancy on fetal development. Reproduction 146(5):R151, 2013