Antivirals

Although zanamivir can be used in pregnancy, oseltamivir is preferred for treatment of pregnant women because of its systemic absorption. Theoretically, higher systemic absorption might suppress influenza viral loads more effectively in sites other than the respiratory system (e.g., placenta) and might provide better protection against mother-child transmission.^3,4

The drug of choice for chemoprophylaxis is less clear. Zanamivir may be preferable because of its limited systemic absorption; however, respiratory complications that may be associated with zanamivir because of its inhaled route of administration need to be considered, especially in women at risk for respiratory problems.

For infection, oseltamivir treatment should be initiated as soon as possible – ideally within 48 hours of onset of symptoms. In addition, any pregnant woman hospitalized with confirmed, probable, or suspected pandemic virus infection should receive oseltamivir, even if more than 48 hours have elapsed since onset of illness. Begin treatment as early as possible.

Dosing is as follows: Oseltamivir: 75 mg BID × 5 days for acute infection, Q day × 10 days for prophylaxis. Zanamivir: Two 5-mg inhalations (10 mg total) BID × 5 days for acute infection, Q day × 10 days for prophylaxis.

SARS

According to the CDC, “Reports suggest that the clinical course and outcomes of SARS might be more severe for pregnant than for non-pregnant women. On the basis of more recent data, the efficacy of ribavirin and corticosteroids in the treatment of patients with SARS has been questioned. Other medications, such as interferons, have been proposed for use in future SARS outbreaks, but use of these medications in pregnant women may also be of concern.”

Monkeypox

According to the CDC, “Because of the high death rate associated with monkeypox on the African continent and lack of experience with monkeypox in the United States, CDC recommended smallpox (vaccinia) vaccination (about 85% effective against monkeypox). Smallpox vaccination during pregnancy poses a low risk for fetal vaccinia, which can lead to preterm birth, and fetal and neonatal death. However, women who were exposed were advised to receive the smallpox vaccine regardless of their pregnancy status, given the life-threatening risk associated with monkeypox infection.”