EXPOSURE TO ANTHRAX AND USE OF ANTHRAX VACCINE IN PREGNANCY
Date of issue: April 2023, Version: 1.0
Anthrax is a bacterial infection caused by Bacillus anthracis. Morbidity and mortality following infection are high, and rapid treatment following exposure is therefore required. An inactivated anthrax vaccine is available and, although not routinely administered, may be offered to individuals at risk of occupational exposure.
When clinically indicated, pregnant women should be treated as for the non-pregnant patient. Discussion with UKTIS is recommended in all cases. Ciprofloxacin is the first-line treatment for anthrax. Amoxicillin may also be used for treatment or prophylaxis but only if the specific strain is known to be penicillin-sensitive.
Published human data regarding maternal anthrax infection are limited to 18 case reports of infection in the latter half of pregnancy. Preterm delivery was reported in three of the cases even after successful treatment of the maternal infection. Intrauterine death preceded maternal death in three severe cases. There are no published reports of fetal outcome following anthrax infection in the first trimester of pregnancy, therefore an evidence-based assessment of malformation risk following first trimester exposure is not possible. Exposure to anthrax at any stage in pregnancy may warrant enhanced fetal monitoring which should be considered on a case-by-case basis. Discussion with UKTIS is recommended in all such cases.
The available published data regarding exposure to the anthrax vaccine during pregnancy describe more than 7,000 first trimester-exposed pregnancies. There is no compelling evidence that exposure to anthrax vaccine in pregnancy is teratogenic. However, data relating to neonatal complication and neurodevelopmental outcomes are lacking.
It is recommended that pregnant women should ideally defer anthrax vaccination, unless they are at risk of exposure to Bacillus anthracis. Advice from the UK Health Security Agency (UKHSA) is that anthrax vaccine may be given to pregnant women when clinically indicated.
Inadvertent exposure to the anthrax vaccine at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy or any additional fetal monitoring. However, other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.