[Originally published online Sept. 1, 2011. Updated and revised in 2013.]

This article addresses disaster agents and the unique risks and management of the pregnant woman, her fetus, and the neonate. The Perinatal Disaster Management tool on the next page summarizes management issues and could be essential in a disaster where rapid access is critical and electronic technology may be absent.

Since the original publication (www.acep.org/Content.aspx??id=82657), there have been important developments.

Influenza: Antivirals: Although zanamivir can be used in pregnancy, oseltamivir is preferred for active infection in pregnant and postpartum women of less than two weeks because of its systemic absorption. Dosing is: Oseltamivir: 75 mg BID X 5 days for acute infection, X 10 days for post-exposure prophylaxis. In a pandemic, pre- and post-exposure prophylaxis should be considered for pregnant women. Dosing for oseltamivir is the same as above; alternate option is zanamivir: two 5-mg inhalations (10 mg total) BID. Duration depends on duration of influenza activity in the community and exposure risk.¹ Influenza vaccine has continually demonstrated safety in pregnancy. ^1,2,3

SARS: According to the CDC, “SARS might be more severe for pregnant than for non-pregnant women.” Ribavirin is no longer recommended for the treatment of coronaviruses or SARS due to the lack of evidence for efficacy and known severe toxicity. Reports also concluded Interferon α, β, and γ may be efficacious in the treatment of SARS; however, more studies are needed to substantiate a recommendation for their use.⁴ No new cases of SARS have been reported in the world since 2004. The “CDC recommends the same treatment that would be used for a patient with any serious community- acquired atypical pneumonia” as the presentations, especially in the acute phase, are similar, and concurrent infections have been well documented.⁵

Anthrax: The CDC further clarifies ciprofloxacin as first line treatment, with use of doxycycline only if a contraindication to other antibiotics exists. Treatment should be switched to amoxicillin if the B. anthracis is found to be sensitive to penicillin.⁶ In regard to the AVA vaccine,⁷ the benefits appear to outweigh risks in cases of a high risk of exposure to inhalational anthrax. In such a case, antibiotic treatment should also be initiated concurrently for 60 days. The vaccine is not recommended for pre-exposure prophylaxis in pregnant women.⁷

Hemorrhagic Fever Virus (HFV)⁸:

According to the San Francisco Department of Public Health, ribavirin is indicated only for suspect or unknown HFV types, suspect or probable Arenavirus (Lassa fever and New World hemorrhagic fever) or Bunyavirus (Rift Valley Fever, Crimean-Congo fever, and “agents of hemorrhagic fever with renal syndrome” such as Hantavirus). It has not been shown efficacious in Filovirus (Ebola and Marburg viruses) or Flavivirus (yellow fever, Omsk hemorrhagic fever, Kyasanur Forest disease, and dengue fever) and is not recommended in such cases.

Fatality is much higher in pregnant women versus non-pregnant women with Lassa and New World hemorrhagic fevers and can be as high as 30% in the third trimester in Lassa fever. Evacuation of the uterus via delivery, spontaneous abortion, or evacuation of retained fetal products can reduce maternal risk of mortality. Fetal and neonatal death has been shown to be as high as 100% and 80% when associated with Ebola virus and Lassa Virus, respectively.

The efficacy of ribavirin for post-exposure prophylaxis is unknown. The mainstay remains prevention, and “strict adherence to infection control measures is essential.” The risk of transmission increases sharply during the latter stages of disease as viral loads are high and hemorrhagic symptoms are more prominent.

Smallpox7: Pregnancy complicated by smallpox infection is more severe than in non-pregnant counterparts and appears to have a significant incidence of miscarriage or premature birth. Vaccination before pregnancy reduced the risk for death. All exposed mothers, as well as all infants and children, should be vaccinated within for days of first exposure.

Although fewer than 50 cases have ever been reported world-wide (three in the United States),⁹ fetal vaccinia may be a risk if mothers receive the vaccine. However, the vaccinia virus is considered to be non-teratogenic.

Smallpox vaccine should not be given as pre-exposure prophylaxis to a woman who is pregnant or who may become pregnant within 28 days. She should also avoid intimate contact or sharing a bed with someone who was vaccinated within 28 days and/or until the vaccination site has completely healed and the scab has come off. A woman who has received the vaccine should not breast feed until after the scab has detached. If a woman has been vaccinated and is pregnant or becomes pregnant within 28 days, there is no indication for induced abortion.⁹

Tularemia: WGCB tularemia recommendations: Antibiotics, the primary classes, streptomycin, gentamicin, quinolones and doxycycline, are often avoided in pregnant and pediatric patients; however, they are recommended based on risk-benefit analysis in bioterrorism settings. A 2012 retrospective study suggested that, while aminoglycosides and tetracyclines are the only FDA approved antibiotics for the treatment of Tularemia, fluoroquinolones may be safer, used for a shorter duration, and have equal efficacy to tetracyclines for alternative outpatient treatment of Francisella Tularensis. Fluoroquinolones are already often used in some regions of the United States, although formal studies are not available.¹⁰

Organophosphates (Nerve Gas):

A retrospective review was done in 2011 of 21 pregnant patients with self-inflicted organophosphate exposure in India. Only atropine was used for treatment, as pralidoxime was not available. They reported that if the mother survived, a favorable short term fetal outcome could be expected, as no congenital abnormality or neurological deficit was observed in any baby.¹¹

Treatment for Nerve Agents (Tabun, Sarin, Soman, and VX): Treatment of organophosphates and nerve agents remains atropine, pralidoxime, and benzodiazepines.

Dr. Roemer is an Adjunct Associate Professor, Department of Emergency Medicine, OU School of Community Medicine, Tulsa, OK. Dr. Cory is a resident, Department of Emergency Medicine, OU School of Community Medicine, Tulsa, OK. Dr. Katz is a clinical professor, Department of Obstetrics and Gynecology, Oregon Health Sciences University, Eugene, Ore.

1. CDC January 21, 2011 / 60(RR01);1-24 www.cdc.gov/flu/professionals/antivirals/antiviral-use-influenza.htm
2. Am J Obstet Gynecol. 2012 Sep;207(3 Suppl):S17-20. doi: 10.1016/j.ajog.2012.06.070. Epub 2012 Jul 9
3. JAMA. 2012 308(2):165-74. doi: 10.1001/jama.2012.6131
4. Int J Gynaecol Obstet. 2009 Oct;107(1):82-6.
5. www.cdc.gov/sars/about/faq.html
6. MMWR July 23, 2010 / 59(rr06);1-30. www.cdc.gov//preview/mmwrhtml/rr5906a1.htm
7. www.cdc.gov/vaccines/pubs/preg-guide.htm
8. www.sfcdcp.com/document.html?id=316
9. http://emergency.cdc.gov/agent/smallpox/faq/pregnancy.asp
10. Clin Infect Dis. 2012 Nov 15;55(10):1283-90. doi: 10.1093/cid/cis706
11. J Obstet Gynaecol. 2011 31:290-2. doi: 10.3109/01443615.2010.545901